Ceramics 3D Printing: A Comprehensive Overview and Applications, with Brief Insights into Industry and Market

: 3D printing enables the creation of complex and sophisticated designs, offering enhanced efficiency, customizability, and cost-effectiveness compared to traditional manufacturing methods. Ceramics, known for their heat resistance, hardness, wear resistance, and electrical insulation properties, are particularly suited for aerospace, automotive, electronics, healthcare, and energy applications. The rise of 3D printing in ceramics has opened new possibilities, allowing the fabrication of complex structures and the use of diverse raw materials, overcoming the limitations of conventional fabrication methods. This review explores the transformative impact of 3D printing, or additive manufacturing, across various sectors, explicitly focusing on ceramics and the different 3D ceramics printing technologies. Furthermore, it presents several active companies in ceramics 3D printing, proving the close relation between academic research and industrial innovation. Moreover, the 3D printed ceramics market forecast shows an annual growth rate (CAGR) of more than 4% in the ceramics 3D printing market, reaching USD 3.6 billion by 2030.


Introduction
3D printing or additive manufacturing constructs parts and products additively, layer by layer, allowing the realization of complex and sophisticated designs [1].3D printing offers high efficiency, customizability, and a low cost when compared to traditional manufacturing [2] and printed parts dimensions can be tiny as few micrometers, as in the case of microelectromechanical systems (MEMS) [3,4], or as large as a few meters, as in the case of printing complete houses [5,6].
3D printing is used in prototyping and product development to create physical models and functional prototypes quickly and cost-effectively.In healthcare, 3D printing enables the production of customized bone implants [7,8] and anatomical models for surgical planning [9,10].It is also employed in the aerospace and automotive sectors for lightweight and complex component manufacturing [11][12][13].Additionally, it facilitates customized manufacturing of jewelry [14] and fashion accessories [15] in the consumer market.
Ceramics are solid materials that consist of inorganic, non-metallic substances.They can exist in two forms: crystalline, which has a structured arrangement, and non-crystalline (amorphous), which lacks a specific pattern [16].Ceramics offer high heat resistance, making them suitable for thermal insulation [17].Their hardness, wear resistance, and chemical inertness are ideal for corrosion-resistant coatings [18] and biomedical implants [19].Ceramics also possess excellent electrical insulation properties, making them valuable in electronic components [20,21].Hence, these versatile properties make ceramics preferred in the aerospace, automotive, electronics, healthcare, and energy industries.
The advent of 3D printing for ceramics [22] presents numerous novel opportunities to overcome the limitations of conventional fabrication techniques like casting and machining [23].These advantages include the capacity to create intricate and precise structures that were previously challenging or impossible to achieve using traditional methods.Additionally, this technology offers the ability to utilize a wide range of feedstock materials in powder form, allowing for the creation of both compact and porous parts and macro-porous ceramic lattice structures [24].
This review article presents the different techniques and processes to prepare 3D printed ceramics, the different materials that are being used and their properties, the design considerations, the ceramic designs optimization for 3D printing, and post-processing and surface finishing techniques.Furthermore, the article highlights the different applications and trends of 3D-printed ceramics.

Ceramics 3D Printing Methods
Several 3D printing techniques exist on both research [25] and industrial levels [26,27].The different and diverse 3D printing technologies can be classified according to the nature of the raw printing materials: liquid, powder, or solid, see Figure 1 [28,29].
Ceramics 2024, 7, FOR PEER REVIEW 2 chemical inertness are ideal for corrosion-resistant coatings [18] and biomedical implants [19].Ceramics also possess excellent electrical insulation properties, making them valuable in electronic components [20,21].Hence, these versatile properties make ceramics preferred in the aerospace, automotive, electronics, healthcare, and energy industries.The advent of 3D printing for ceramics [22] presents numerous novel opportunities to overcome the limitations of conventional fabrication techniques like casting and machining [23].These advantages include the capacity to create intricate and precise structures that were previously challenging or impossible to achieve using traditional methods.Additionally, this technology offers the ability to utilize a wide range of feedstock materials in powder form, allowing for the creation of both compact and porous parts and macro-porous ceramic lattice structures [24].
This review article presents the different techniques and processes to prepare 3D printed ceramics, the different materials that are being used and their properties, the design considerations, the ceramic designs optimization for 3D printing, and post-processing and surface finishing techniques.Furthermore, the article highlights the different applications and trends of 3D-printed ceramics.

Ceramics 3D Printing Methods
Several 3D printing techniques exist on both research [25] and industrial levels [26,27].The different and diverse 3D printing technologies can be classified according to the nature of the raw printing materials: liquid, powder, or solid, see Figure 1 [28,29].Figure 2 shows the different types of ceramic materials.Ceramic materials can be classified into three types: oxides, non-oxides, and composites [30][31][32], as shown in the figure .Ceramics 3D printing as conventional 3D printing covers a multi-stage process, initiating with the design and CAD phase, during which a conceptual design is made using computer-aided design tools [33].This is followed by File Conversion, where the CAD model is translated into a format that the printer understands (ex: GCODE) [34,35].Subsequently, Machine Setup involves preparing the 3D printer and calibrating it according to the specific requirements of the ceramic material.The Printing stage then commences, where the ceramic material is meticulously layered and shaped according to the design specifications.Post-printing, the object undergoes a Drying process to eliminate any residual moisture, ensuring structural integrity.This is followed by Sintering, a critical heat treatment step that fuses the ceramic particles at a high temperature to achieve the desired density and strength.The final stage, Post-Processing, encompasses various finishing techniques, such as cleaning and surface smoothing, to enhance the aesthetic and functional qualities of the printed object [36,37].Figure 3 from left to right shows the steps from producing the design to the finishing steps.Ceramics 3D printing as conventional 3D printing covers a multi-stage process, initiating with the design and CAD phase, during which a conceptual design is made using computer-aided design tools [33].This is followed by File Conversion, where the CAD model is translated into a format that the printer understands (ex: GCODE) [34,35].Subsequently, Machine Setup involves preparing the 3D printer and calibrating it according to the specific requirements of the ceramic material.The Printing stage then commences, where the ceramic material is meticulously layered and shaped according to the design specifications.Post-printing, the object undergoes a Drying process to eliminate any residual moisture, ensuring structural integrity.This is followed by Sintering, a critical heat treatment step that fuses the ceramic particles at a high temperature to achieve the desired density and strength.The final stage, Post-Processing, encompasses various finishing techniques, such as cleaning and surface smoothing, to enhance the aesthetic and functional qualities of the printed object [36,37].Figure 3 from left to right shows the steps from producing the design to the finishing steps.Ceramics 3D printing as conventional 3D printing covers a multi-stage process, initiating with the design and CAD phase, during which a conceptual design is made using computer-aided design tools [33].This is followed by File Conversion, where the CAD model is translated into a format that the printer understands (ex: GCODE) [34,35].Subsequently, Machine Setup involves preparing the 3D printer and calibrating it according to the specific requirements of the ceramic material.The Printing stage then commences, where the ceramic material is meticulously layered and shaped according to the design specifications.Post-printing, the object undergoes a Drying process to eliminate any residual moisture, ensuring structural integrity.This is followed by Sintering, a critical heat treatment step that fuses the ceramic particles at a high temperature to achieve the desired density and strength.The final stage, Post-Processing, encompasses various finishing techniques, such as cleaning and surface smoothing, to enhance the aesthetic and functional qualities of the printed object [36,37].Figure 3 from left to right shows the steps from producing the design to the finishing steps.

Stereolithography (SLA)
SLA employs a reservoir of liquid photopolymer resin that undergoes curing (solidification) via a UV laser.The laser precisely solidifies the resin layer by layer, fabricating intricate and high-resolution components.SLA is widely favored for manufacturing elaborate prototypes and objects featuring smooth surface textures.
SLA 3D printed ceramics printing resin/solution is prepared by mixing the light curable resin with ceramic powder and then post-processing the printed green parts through sintering and debinding processes.Dong's group 3D printed Calcium Phosphate Bioceramics, as shown in Figure 4, using SLA technology.Sotov's group 3D printed barium titanate (BaTiO 3 )-UV resin using SLA technology, as shown in Figure 5.
orate prototypes and objects featuring smooth surface textures.
SLA 3D printed ceramics printing resin/solution is prepared by mixing the light curable resin with ceramic powder and then post-processing the printed green parts through sintering and debinding processes.Dong's group 3D printed Calcium Phosphate Bioceramics, as shown in Figure 4, using SLA technology.Sotov's group 3D printed barium titanate (BaTiO3)-UV resin using SLA technology, as shown in Figure 5.   intricate and high-resolution components.SLA is widely favored for manufacturing elaborate prototypes and objects featuring smooth surface textures.
SLA 3D printed ceramics printing resin/solution is prepared by mixing the light curable resin with ceramic powder and then post-processing the printed green parts through sintering and debinding processes.Dong's group 3D printed Calcium Phosphate Bioceramics, as shown in Figure 4, using SLA technology.Sotov's group 3D printed barium titanate (BaTiO3)-UV resin using SLA technology, as shown in Figure 5.

Digital Light Processing (DLP)
DLP shares similarities with SLA; however, instead of a laser or UV light, it relies on a digital light projector to cure the photopolymer resin.DLP boasts quicker print times when compared to conventional SLA methods.Yao's group fabricated high-performance hydroxyapatite (HA) ceramics using digital light processing (DLP) 3D printing technology.They suggested that the improvement in densification and mechanical properties was achieved by sintering in a wet CO 2 atmosphere [40].
Figure 6 shows a lab made DLP printer that Liu's group used to 3D print a Porous β-Tricalcium Phosphate scaffold that can be used in bone regeneration.
when compared to conventional SLA methods.Yao's group fabricated high-performance hydroxyapatite (HA) ceramics using digital light processing (DLP) 3D printing technology.They suggested that the improvement in densification and mechanical properties was achieved by sintering in a wet CO2 atmosphere [40].
Figure 6 shows a lab made DLP printer that Liu's group used to 3D print a Porous β-Tricalcium Phosphate scaffold that can be used in bone regeneration.Guo's group demonstrated the potential of Digital Light Processing (DLP) 3D printing for fabricating fine lattice structures in titanium dioxide ceramics, as shown in Figure 7, achieving controllable porosity between 50% and 80%.The research detailed the process of preparing a suitable slurry, optimizing debinding and sintering parameters to prevent cracking and collapse, and achieving strut precision of 200 μm.The resulting rutile phase titanium dioxide ceramics exhibited a compressive strength that improved with decreased porosity, suggesting potential for high-strength applications.This advancement in 3D printing techniques opens new possibilities for the use of titanium dioxide ceramics in fields requiring porous structures, such as bone tissue engineering and catalytic systems [42], as shown in Figure 7.  Guo's group demonstrated the potential of Digital Light Processing (DLP) 3D printing for fabricating fine lattice structures in titanium dioxide ceramics, as shown in Figure 7, achieving controllable porosity between 50% and 80%.The research detailed the process of preparing a suitable slurry, optimizing debinding and sintering parameters to prevent cracking and collapse, and achieving strut precision of 200 µm.The resulting rutile phase titanium dioxide ceramics exhibited a compressive strength that improved with decreased porosity, suggesting potential for high-strength applications.This advancement in 3D printing techniques opens new possibilities for the use of titanium dioxide ceramics in fields requiring porous structures, such as bone tissue engineering and catalytic systems [42], as shown in Figure 7.
DLP shares similarities with SLA; however, instead of a laser or UV light, it relies on a digital light projector to cure the photopolymer resin.DLP boasts quicker print times when compared to conventional SLA methods.Yao's group fabricated high-performance hydroxyapatite (HA) ceramics using digital light processing (DLP) 3D printing technology.They suggested that the improvement in densification and mechanical properties was achieved by sintering in a wet CO2 atmosphere [40].
Figure 6 shows a lab made DLP printer that Liu's group used to 3D print a Porous β-Tricalcium Phosphate scaffold that can be used in bone regeneration.Guo's group demonstrated the potential of Digital Light Processing (DLP) 3D printing for fabricating fine lattice structures in titanium dioxide ceramics, as shown in Figure 7, achieving controllable porosity between 50% and 80%.The research detailed the process of preparing a suitable slurry, optimizing debinding and sintering parameters to prevent cracking and collapse, and achieving strut precision of 200 μm.The resulting rutile phase titanium dioxide ceramics exhibited a compressive strength that improved with decreased porosity, suggesting potential for high-strength applications.This advancement in 3D printing techniques opens new possibilities for the use of titanium dioxide ceramics in fields requiring porous structures, such as bone tissue engineering and catalytic systems [42], as shown in Figure 7.

Direct-Ink-Writing (DIW)
DIW, or Robocasting, is an advanced 3D printing technique fabricating complex structures through precise material deposition layer-by-layer.In this additive manufacturing process, a nozzle or pen-like dispenser releases a liquid or semi-liquid substance, typically a blend of polymers and other components, onto a substrate.The material is then extruded from the nozzle and rapidly solidifies upon deposition, resulting in the desired 3D structure.
DIW finds widespread application in producing ceramic or metal components, which are subsequently consolidated through an oven process.Additionally, it is commonly used for bioprinting various materials, enabling the creation of intricate biological structures.
Jin's group prepared highly porous ceramics that possessed high mechanical and dielectric properties; such structures can have several uses, including in filters, catalyst supports, and thermal insulators, as shown in Figure 8.
turing process, a nozzle or pen-like dispenser releases a liquid or semi-liquid substance, typically a blend of polymers and other components, onto a substrate.The material is then extruded from the nozzle and rapidly solidifies upon deposition, resulting in the desired 3D structure.
DIW finds widespread application in producing ceramic or metal components, which are subsequently consolidated through an oven process.Additionally, it is commonly used for bioprinting various materials, enabling the creation of intricate biological structures.
Jin's group prepared highly porous ceramics that possessed high mechanical and dielectric properties; such structures can have several uses, including in filters, catalyst supports, and thermal insulators, as shown in Figure 8.

Selective Laser Sintering (SLS)
SLS 3D printed ceramics can be direct or indirect.In direct SLS, the ceramic powder layers are locally heated and fused using a laser beam as the heat source.On the other hand, indirect SLS involves the laser melting of an organic binder phase within the polymer-ceramic composite powder to create preliminary "green" parts.A debinding and furnace sintering process is required to obtain the final ceramic parts.
SLS underwent extensive development and found application in the production of dense and cellular ceramic components.This technology served various industries by facilitating the creation of parts with complex designs, including integrally cored casting molds.Chen's group realized several advanced fused silica ceramic parts ranging from scaffolds to casting molds [23,44,45].Figure 9 shows the basic setup of the SLS 3D silica ceramics printing.

Selective Laser Sintering (SLS)
SLS 3D printed ceramics can be direct or indirect.In direct SLS, the ceramic powder layers are locally heated and fused using a laser beam as the heat source.On the other hand, indirect SLS involves the laser melting of an organic binder phase within the polymerceramic composite powder to create preliminary "green" parts.A debinding and furnace sintering process is required to obtain the final ceramic parts.
SLS underwent extensive development and found application in the production of dense and cellular ceramic components.This technology served various industries by facilitating the creation of parts with complex designs, including integrally cored casting molds.Chen's group realized several advanced fused silica ceramic parts ranging from scaffolds to casting molds [23,44,45].Figure 9 shows the basic setup of the SLS 3D silica ceramics printing.

Selective Laser Melting (SLM)
SLM is a relatively recent addition to 3D-printing methods, originating in 1995 through the efforts of German scientists [47].Like SLA, which employs UV light, SLM utilizes a powerful laser beam to construct 3D components.In this process, the laser beam

Selective Laser Melting (SLM)
SLM is a relatively recent addition to 3D-printing methods, originating in 1995 through the efforts of German scientists [47].Like SLA, which employs UV light, SLM utilizes a powerful laser beam to construct 3D components.In this process, the laser beam effectively melts and blends diverse metallic powders, selectively joining or welding the particles together as it strikes each thin material layer.

Binder Jetting (BJ)
Two materials are employed in the binder jetting process: powder-based and binder.The binder functions as an adhesive, bonding the powder layers together.Typically, the binder is a liquid, while the build material is a powder [48].BJ ceramics 3D printing overcomes the problems of printing complex shapes and eliminates the need for sintering, which shrinks the original printed part's dimensions [49].The BJ process has been successfully applied to large-scale production of ceramic parts with resolutions in the centimeter scale, while also providing sustainability benefits.Zocca's group demonstrated the capability of BJ by printing a large artwork piece that was 1.28 m wide, with the potential to be printed up to a diameter of 3.5 m using the same equipment [50].Figure 10 shows the basic setup of the BJ 3D ceramics printing.

Selective Laser Melting (SLM)
SLM is a relatively recent addition to 3D-printing methods, originating i through the efforts of German scientists [47].Like SLA, which employs UV ligh utilizes a powerful laser beam to construct 3D components.In this process, the lase effectively melts and blends diverse metallic powders, selectively joining or weldi particles together as it strikes each thin material layer.

Binder Jetting (BJ)
Two materials are employed in the binder jetting process: powder-based and b The binder functions as an adhesive, bonding the powder layers together.Typical binder is a liquid, while the build material is a powder [48].BJ ceramics 3D printing comes the problems of printing complex shapes and eliminates the need for sin which shrinks the original printed part's dimensions [49].The BJ process has bee cessfully applied to large-scale production of ceramic parts with resolutions in the meter scale, while also providing sustainability benefits.Zocca's group demonstra capability of BJ by printing a large artwork piece that was 1.28 m wide, with the po to be printed up to a diameter of 3.5 m using the same equipment [50].Figure 10 the basic setup of the BJ 3D ceramics printing.

Fused Deposition Modeling (FDM)
FDM ranks among the most extensively employed 3D printing methods.This technique involves the gradual extrusion of a heated thermoplastic filament through a nozzle, which subsequently deposits the material layer by layer, thereby constructing the desired 3D object.Due to their affordability, FDM printers have gained popularity among makers and small-scale applications.Masuda's group modified a FDM 3D printed to print SiC ceramic structures [51], as shown in Figure 11.

75
FDM ranks among the most extensively employed 3D printing methods.This technique involves the gradual extrusion of a heated thermoplastic filament through a nozzle, which subsequently deposits the material layer by layer, thereby constructing the desired 3D object.Due to their affordability, FDM printers have gained popularity among makers and small-scale applications.Masuda's group modified a FDM 3D printed to print SiC ceramic structures [51], as shown in Figure 11.

Laminated Object Manufacturing (LOM)
LOM technology is based on bonding sheets of the printed materials and then cutting the unwanted parts; this results in the formation of the desired 3D part, as shown in Figure 12.In ceramics, LOM involves bonding layers of ceramic-based sheets or films using heat or an adhesive to create intricate ceramic parts with improved mechanical properties and high temperature resistance.It finds applications in the aerospace, electronics, and engineering industries due to its ability to produce complex and robust ceramic objects.Zhang's group yielded alumina 3D printed parts with porosities of 51.5% and round hole diameters of 80 ± 5 μm.The use of an organic mesh as a framework and template reduced the risk of damage to the green body while ensuring regularity, uniformity, and connectivity of the micron-scaled pore network [52].Figure 12 shows the basic setup of LOM 3D printing.

Laminated Object Manufacturing (LOM)
LOM technology is based on bonding sheets of the printed materials and then cutting the unwanted parts; this results in the formation of the desired 3D part, as shown in Figure 12.In ceramics, LOM involves bonding layers of ceramic-based sheets or films using heat or an adhesive to create intricate ceramic parts with improved mechanical properties and high temperature resistance.It finds applications in the aerospace, electronics, and engineering industries due to its ability to produce complex and robust ceramic objects.Zhang's group yielded alumina 3D printed parts with porosities of 51.5% and round hole diameters of 80 ± 5 µm.The use of an organic mesh as a framework and template reduced the risk of damage to the green body while ensuring regularity, uniformity, and connectivity of the micron-scaled pore network [52].Figure 12 shows the basic setup of LOM 3D printing.
nique involves the gradual extrusion of a heated thermoplastic filament through a nozzle, which subsequently deposits the material layer by layer, thereby constructing the desired 3D object.Due to their affordability, FDM printers have gained popularity among makers and small-scale applications.Masuda's group modified a FDM 3D printed to print SiC ceramic structures [51], as shown in Figure 11.

Laminated Object Manufacturing (LOM)
LOM technology is based on bonding sheets of the printed materials and then cutting the unwanted parts; this results in the formation of the desired 3D part, as shown in Figure 12.In ceramics, LOM involves bonding layers of ceramic-based sheets or films using heat or an adhesive to create intricate ceramic parts with improved mechanical properties and high temperature resistance.It finds applications in the aerospace, electronics, and engineering industries due to its ability to produce complex and robust ceramic objects.Zhang's group yielded alumina 3D printed parts with porosities of 51.5% and round hole diameters of 80 ± 5 μm.The use of an organic mesh as a framework and template reduced the risk of damage to the green body while ensuring regularity, uniformity, and connectivity of the micron-scaled pore network [52].Figure 12 shows the basic setup of LOM 3D printing.

Directed Energy Deposition (DED)
One of the most promising techniques for 3D ceramic printing is DED.DED is an additive manufacturing process where focused thermal energy, such as a laser or electron beam, is used to fuse materials by melting them as they are deposited [54,55].In the context of ceramics, DED allows for the creation of intricate and complex structures with high precision, layer by layer.This method not only offers rapid prototyping capabilities but also ensures enhanced mechanical properties and reduced material wastage.The integration of DED in ceramic printing holds immense promise for industries ranging from aerospace to biomedical, paving the way for innovative solutions and designs previously deemed unattainable.Figure 13 shows the basic setup of DED ceramic 3D printing.
One of the most promising techniques for 3D ceramic printing is DED.DED is an additive manufacturing process where focused thermal energy, such as a laser or electron beam, is used to fuse materials by melting them as they are deposited [54,55].In the context of ceramics, DED allows for the creation of intricate and complex structures with high precision, layer by layer.This method not only offers rapid prototyping capabilities but also ensures enhanced mechanical properties and reduced material wastage.The integration of DED in ceramic printing holds immense promise for industries ranging from aerospace to biomedical, paving the way for innovative solutions and designs previously deemed unattainable.Figure 13 shows the basic setup of DED ceramic 3D printing.

Debinding
Debinding is the process of removing the organic binders used during the printing process.The goal is to eliminate these binders without causing defects or damage to the green part.Debinding can be performed using thermal, solvent, or catalytic methods depending on the binder and material system.Careful control of temperature and atmosphere is essential during debinding to avoid cracking or warping of the green part.The removal of the binders prepares the part for the subsequent sintering.The time and temperature used for debinding affect the final ceramic structures [56,57].

Debinding
Debinding is the process of removing the organic binders used during the printing process.The goal is to eliminate these binders without causing defects or damage to the green part.Debinding can be performed using thermal, solvent, or catalytic methods depending on the binder and material system.Careful control of temperature and atmosphere is essential during debinding to avoid cracking or warping of the green part.The removal of the binders prepares the part for the subsequent sintering.The time and temperature used for debinding affect the final ceramic structures [56,57].

Sintering
Sintering is a critical step in ceramic 3D printing that transforms the green part into a solid ceramic object.During sintering, the ceramic particles are heated to the point where they bond together, achieving the desired density and mechanical properties.The sintering process involves various parameters, including temperature, atmosphere, and heating rate, which must be precisely controlled to avoid warping and shrinkage.
Sintering of 3D printed ceramics can be conducted using different methods, such as traditional furnace sintering [58,59], microwave sintering [60,61], or spark plasma sintering (SPS) [62,63].The choice of sintering method depends on the specific ceramic material and the desired properties of the final part.

Surface finishing
Surface finishing is a critical aspect of ceramic 3D printing, as it enhances the aesthetics and performance of the final ceramic part.Depending on the application and desired characteristics, various techniques can be applied.For instance, polishing can be used to achieve a smooth and glossy surface finish, while glazing provides a protective and decorative layer [64].Machining processes may also be employed to precisely shape and refine the part's dimensions.The choice of surface finishing method depends on the specific application and the requirements for the final ceramic part.Achieving the desired surface finish may require several iterations of post-processing.

Biomedical Implants and Devices
The exploration of 3D printed ceramics and other materials in the field of biomedical implants and devices marks a significant advancement in medical technology.Sandeep's group evaluated the use of PEEK (Polyether ether ketone) and stainless steel, highlighting their biocompatibility and suitability for medical applications [65].Das's group focused on integrating 2D nanomaterials with ceramics 3D printing, revealing potential advancements in drug delivery and tissue engineering [66].Mamo et al. provided a comprehensive review of 3D printing technologies in the medical sector, including 3D printed ceramics, discussing the challenges and future perspectives of using materials like ceramics and composites [67].Lastly, Samuel Hales et al. emphasized the integration of nanomaterials in 3D printed devices, leading to the creation of innovative biomedical and bioelectronic devices [68].These studies showcased the significant advancements and diverse applications of 3D printing and 3D printed ceramics in the biomedical field.This innovative approach of ceramics 3D printing for biomedical applications offers several benefits: 1.
Customization and Personalization: 3D printing allows for the creation of implants and devices that are custom fitted to individual patients.This personalization ensures better compatibility and comfort, leading to improved patient outcomes.

2.
Complex Structures: 3D printing makes it possible to create structures with intricate geometries that mimic the natural complexity of human tissues and bones.This capability is crucial for implants that need to integrate seamlessly with the body's own systems.

3.
Material Diversity: The use of various materials, including ceramics, polymers, and metals, in 3D printing provides flexibility in terms of mechanical properties and biocompatibility.Ceramics, for instance, are particularly useful for their bone-like properties and durability.4.
Rapid Prototyping: The technology enables quick production and iteration of prototypes.This rapid prototyping is essential in the medical field, where time is often a critical factor.5.
Cost-Effectiveness: Producing custom implants and devices traditionally is expensive.3D printing can reduce these costs, making personalized medical care more accessible.6.
Improved Healing and Integration: 3D printed materials can be designed to encourage tissue growth and integration, leading to faster and more effective healing.7.
Innovation in Treatment: The ability to print complex devices opens new possibilities in treating conditions that were previously difficult to manage with standard implants.8.
Reduced Surgical Time: Customized implants that fit perfectly can reduce the duration of surgeries and the associated risks.

Aerospace and Automotive Components
3D printed ceramics are transforming the aerospace and automotive industries by offering groundbreaking solutions to intricate engineering problems.Advanced ceramics like aluminum oxide, silicon nitride, silicon carbide, and zirconia are prized for their high resistance to heat, oxidation, abrasion, and their mechanical and dimensional stability [69][70][71].These properties make ceramics ideal for next-generation spacecraft construction, particularly for parts exposed to high stresses [72].For example, the aerospike engine nozzle, made of silicon nitride, is capable of withstanding temperatures over 1200 • C and exemplifies the durability and heat resistance of these materials [73].The integration of 3D printed ceramics in the aerospace and automotive industries showcases the material's potential in creating lighter, stronger, and more efficient components.This technology stands out due to several factors: Enhanced Material Properties: Ceramics are known for their high strength, thermal resistance, and durability, making them ideal for aerospace and automotive applications.3D printing allows for the production of ceramic parts that are lighter yet stronger, significantly improving the performance and efficiency of vehicles and aircraft.

2.
Complex Geometries: Traditional manufacturing methods often fall short in creating complex shapes required in aerospace and automotive engineering.3D printing excels at this, allowing for the creation of components with intricate designs and internal structures that were previously impossible or too costly to produce.

3.
Reduced Weight and Increased Efficiency: In both aerospace and automotive sectors, weight is a critical factor.3D printed ceramic parts contribute to significant weight reduction, leading to improved fuel efficiency and lower emissions, crucial in an era where environmental impact is a major concern.4.
Customization and Rapid Prototyping: 3D printing enables the quick production of customized parts tailored to specific requirements.This flexibility is invaluable for prototyping and testing new designs, speeding up the development process and allowing for more innovation and experimentation.5.
Cost Reduction: Manufacturing complex parts often involves high costs, especially in small volumes.3D printing reduces these costs by simplifying the production process and minimizing material waste, making it a cost-effective solution for both small-scale prototypes and larger production runs.6.
Improved Performance: The unique properties of ceramics, combined with the precision of 3D printing, result in parts that perform better under extreme conditions.This is particularly important in aerospace applications where components need to withstand high temperatures and pressures.7.
Sustainability: The additive manufacturing process of 3D printing is more sustainable compared to traditional subtractive methods.It produces less waste and consumes less energy, aligning with the growing trend towards more environmentally friendly manufacturing practices in these industries.

Consumer Electrical Goods and Electronics
The emergence of 3D-printed ceramics in the manufacturing of Printed Circuit Boards (PCBs) represents a significant leap in the field of consumer electronics.Traditional PCB fabrication is a time-consuming process involving repetitive milling and etching, using hazardous chemicals, and generating significant waste.In consumer electronics, rapid prototyping is essential for product development.The ceramics 3D printing can be crucial in electronics for high-temperature environments [74].This innovative approach stands out for several key reasons: 1.
In-House Manufacturing: With 3D printing technology, companies can produce PCBs in-house.This capability is crucial in circumventing supply chain issues, a common challenge in traditional manufacturing.It ensures a more stable and reliable production flow, thereby reducing the dependency on external suppliers and mitigating risks related to delays or disruptions.

2.
Complex Circuit Design: 3D printing allows for the creation of more intricate and complex circuit designs than traditional methods.This flexibility enables the development of advanced electronic devices with enhanced capabilities, as 3D printing can accurately produce fine details and accommodate unique geometric configurations.

3.
Speed and Cost-Effectiveness: The process of 3D printing PCBs is generally faster compared to traditional manufacturing techniques.This efficiency is due to the direct-from-design-to-production approach, which eliminates several steps involved in conventional manufacturing.Moreover, 3D printing can be more cost-effective, especially for small batch production and prototyping, as it requires less material waste and reduces the need for multiple tools and molds.4.
Customization and Prototyping: 3D printing offers unparalleled customization options.Designers can quickly alter designs and produce prototypes without the need for extensive retooling, facilitating rapid prototyping and testing.This agility accelerates the development cycle, allowing for faster iteration and innovation. 5.
Environmental Impact: The additive nature of 3D printing, where material is added rather than removed, leads to less waste compared to subtractive manufacturing processes.This aspect contributes to more sustainable manufacturing practices, aligning with the growing emphasis on environmental responsibility in the electronics industry.
A new insight is relating the type of ceramics, their properties, and the possible applications sectors.Table 2 shows this relationship.The realm of 3D printing ceramics is a vibrant intersection where innovative academic research meets cutting-edge industrial application.Various companies have become pivotal in this field, each contributing unique technologies and insights that have expanded the boundaries of what is possible with ceramic materials.Companies like 3D Systems [78], Voxeljet AG [79], Admatec BV [80], Lithoz [81], Wasp S.r.l.[82], Tethon 3D [83], 3Dceram [84], Prodways [85], 3D potters [86], Nanoe [87], and more are at the forefront of this revolution.They are not only implementing and refining existing 3D printing techniques, but also pioneering new methods and materials, thereby transforming the way ceramics are used in industries ranging from biomedical to aerospace.The synergy between academic research and these industrial companies is crucial.It facilitates the translation of theoretical innovations into practical, market-ready solutions, ensuring that the advancements in ceramic 3D printing continue to evolve at a pace that matches the rapid growth of both technological capabilities and market demands.This collaborative approach is key to unlocking the full potential of 3D printed ceramics, paving the way for new applications and more efficient manufacturing processes.Table 3 shows several companies that are active in the ceramics 3D printing industry and market, alongside their unique aspects and technology.The global forecast of the 3D printed ceramics shows a promising growth in the market.Figure 14 shows the growth in the global 3D printed ceramics market, with a projected growth of the global ceramic 3D printing market from 2021 to 2030.In 2021, the market was valued at approximately USD 2.5 billion and is expected to grow to around USD 3.55 billion by 2030.This trend represents a significant increase, reflecting the expanding role and adoption of ceramic 3D printing technologies in various industries.The significant rise reflects the growing adoption of ceramics 3D printing technology in different applications, including aerospace, defense, and healthcare sectors.
growth of the global ceramic 3D printing market from 2021 to 2030.In 2021, the market was valued at approximately USD 2.5 billion and is expected to grow to around USD 3.55 billion by 2030.This trend represents a significant increase, reflecting the expanding role and adoption of ceramic 3D printing technologies in various industries.The significant rise reflects the growing adoption of ceramics 3D printing technology in different applications, including aerospace, defense, and healthcare sectors.

Conclusions
In conclusion, ceramics exhibit exceptional material properties, encompassing elevated thermal resistance, electrical insulating characteristics, high hardness, and notable wear resistance.The incorporation of additive manufacturing, specifically 3D printing, into the realm of ceramics manufacturing represents a seminal advancement in the field of materials science and engineering.This study underscores how this technology transcends the confines of traditional ceramics manufacturing methodologies, extending design boundaries and augmenting the functional attributes of ceramic components.The capacity to fabricate intricate geometries and microstructures hitherto unattainable via conventional means heralds a new era of possibilities across various industries, notably within the aerospace, healthcare, electronics, and automotive sectors.
Furthermore, this investigation highlights the ongoing progress in optimizing raw material compositions and refining printing techniques specific to 3D printed ceramics.These advancements signify the immense potential of 3D printed ceramics in addressing distinctive industrial challenges, thereby establishing a fertile ground for pioneering applications and continued research endeavors in the realm of advanced materials.
In essence, the confluence of ceramics and 3D printing technology signifies a harmonious unification of established material excellence and innovative additive manufactur-

Conclusions
In conclusion, ceramics exhibit exceptional material properties, encompassing elevated thermal resistance, electrical insulating characteristics, high hardness, and notable wear resistance.The incorporation of additive manufacturing, specifically 3D printing, into the realm of ceramics manufacturing represents a seminal advancement in the field of materials science and engineering.This study underscores how this technology transcends the confines of traditional ceramics manufacturing methodologies, extending design boundaries and augmenting the functional attributes of ceramic components.The capacity to fabricate intricate geometries and microstructures hitherto unattainable via conventional means heralds a new era of possibilities across various industries, notably within the aerospace, healthcare, electronics, and automotive sectors.
Furthermore, this investigation highlights the ongoing progress in optimizing raw material compositions and refining printing techniques specific to 3D printed ceramics.These advancements signify the immense potential of 3D printed ceramics in addressing distinctive industrial challenges, thereby establishing a fertile ground for pioneering applications and continued research endeavors in the realm of advanced materials.
In essence, the confluence of ceramics and 3D printing technology signifies a harmonious unification of established material excellence and innovative additive manufacturing capabilities, particularly in the industrial and consumer market.This fusion holds significant promise, and as research and development efforts persist, it is poised to engender a transformative paradigm shift across diverse industries.Ultimately, this synergy promises to reshape the trajectory of materials science and engineering, with far-reaching implications and pioneering contributions to scholarly and industrial domains alike.

Figure 2
Figure2shows the different types of ceramic materials.Ceramic materials can be classified into three types: oxides, non-oxides, and composites[30][31][32], as shown in the figure.

Figure 8 .
Figure 8.(a) Flow chart of the fabrication route for direct ink writing of porous ceramic based on strong colloidal gel ink without sedimentable organic phase.(b) 3D printing frame structure.(c) 3D printing honeycomb structure.(d) 3D printing cellular structure (scale bar 1 cm) [43].

Figure 8 .
Figure 8.(a) Flow chart of the fabrication route for direct ink writing of porous ceramic based on strong colloidal gel ink without sedimentable organic phase.(b) 3D printing frame structure.(c) 3D printing honeycomb structure.(d) 3D printing cellular structure (scale bar 1 cm) [43].

Figure 12 .
Figure 12.Basic schematic of the LOM process, to which additional processing steps may be added.The continuous flow of sheet material is marked by red arrows [53].

Figure 12 .
Figure 12.Basic schematic of the LOM process, to which additional processing steps may be added.The continuous flow of sheet material is marked by red arrows [53].

Figure 12 .
Figure 12.Basic schematic of the LOM process, to which additional processing steps may be added.The continuous flow of sheet material is marked by red arrows [53].

Figure 14 .
Figure 14.3D printed ceramics forecast according to spherical insights market's forecast data for the years 2021 and 2030 [88].

Figure 14 .
Figure 14.3D printed ceramics forecast according to spherical insights market's forecast data for the years 2021 and 2030 [88].

Table 1
summarizes the different ceramics 3D printing technologies and compares them in different aspects.

Table 1 .
Comparison between different 3D ceramics techniques.

Table 1
summarizes the different ceramics 3D printing technologies and compares them in different aspects.

Table 1 .
Comparison between different 3D ceramics techniques.

Table 2 .
Ceramics, their properties, and possible applications.

Table 3 .
Examples of active companies in the area of ceramics 3D printing and their leading technologies and business focus.