Effect of Sintering Temperatures, Reinforcement Size on Mechanical Properties and Fortification Mechanisms on the Particle Size Distribution of B4C, SiC and ZrO2 in Titanium Metal Matrix Composites

Titanium metal matrix composites/TMMCs are reinforced ceramic reinforcements that have been developed and used in the automotive, biological, implants, and aerospace fields. At high temperatures, TMMCs can provide up to 50% weight reduction compared to monolithic super alloys while maintaining comparable quality or state of strength. The objective of this research was the analysis and evaluation of the effect/influence of different sintering temperatures, reinforcement size dependence of mechanical properties, and fortification mechanisms on the particle size distribution of B4C, SiC, and ZrO2 reinforced TMMCs that were produced and fabricated by powder metallurgy/PM. SEM, XRD, a Rockwell hardness tester, and the Archimedes principle were used in this analysis. The composites’ hardness, approximation, tensile, yielding, and ultimate strength were all increased. As the composite was reinforced with low-density ceramics material and particles, its density decreased. The volume and void content in all the synthesized specimens is below 1%; this is the result of good sample densification, mechanical properties and uniform distribution of the reinforced particle samples; 5% B4C, 12.5% SiC, 7.5% ZrO2, 75% Ti develop higher mechanical properties, such as higher hardness, approximation tensile, yielding, and ultimate strength and low porosity.


Introduction
Metal matrix composites (MMCs) are gaining popularity in scientific and industry circles due to their appealing physical, and mechanical qualities and have tremendous potential for use in the automobile and aerospace industries [1]. When compared to conventional and homogeneous metal alloys [2], particle-armored MMCs have superior mechanical properties, such as strengthening and stiffening [3,4], hardness [5,6], and fracture use of the benefits of smaller reinforcing particles, such as reduced stress concentration, it is necessary to minimize/eliminate nanoparticle agglomerates and establish a homogeneous spatial contribution and spread of individual particles throughout the matrix. Second, it is acknowledged that the structure and chemistry of matrix/reinforcement interfaces have a significant impact on the mechanical properties, and cryo-milling reduces interfacial modifications by suppressing diffusion and chemical reactions at cryogenic temperatures and separating reactive nanoparticle powders from the environment. Third, B 4 C is intriguing because it has a very high hardness at room temperature, which is only slightly lower than that of cubic BN and diamond; at temperatures exceeding 1200 • C, its own hardness has been shown to exceed that of diamond. Furthermore, B 4 C is cheaper and less challenging to create than diamond and cubic BN. These properties, together with its high melting point, low density, and extraordinary chemical inertness, make B 4 C an excellent reinforcement for a wide range of metals and found that Ti composites containing nano dimension B 4 C particles had higher strength and better tensile ductility than those with micro dimensions B 4 C particles [41,42]. Fourth, zirconium dioxide (ZrO 2 ) has outstanding biomechanical qualities, such as fracture strength, toughness, and fatigue resistance, low elasticity module and strength, as well as high wear resistance and bio-compatibility. Powder metallurgy has been stated as the method of combining, pressing, and sintering the ingredients of a composite. PM is the most effective production process and method for generating homogeneous composite materials. This approach produces exceptional characteristics by achieving good uniformity and low porosity. Fifth, SiC reinforcing was chosen as reinforcement due to its corrosion resistance, high strength, outstanding thermal stability, formability, ductility, stiffness, low cost, and other characteristics. In this study, powder metallurgy was utilized to synthesize Ti-B 4 C, SiC, and ZrO 2 nanocomposites. The mechanical characteristics of the developed TMCs materials' microstructure, densification, micro hardness, sintering temperature influence, and reinforcement size dependence and distribution have all been investigated.

Experimental Procedure and Work
Titanium with nanoparticles size 100 nm, purity > 90%, and reinforcement of nanoparticle powders of B 4 C, SiC, and ZrO 2 with a particle size of 100 nm were acquired from METALFORT Company, Mumbai, India, and utilized as starting materials. To achieve this, powder metallurgy was used to make Ti-B 4 C, SiC, and ZrO 2 nanocomposites in this study. These mechanical characteristics of the developed and produced TMCs materials, including microstructure, densification, micro hardness, sintering temperature influence, and reinforcement size dependence and distribution, have all been studied. The effect of reinforcement size and hardness was measured with a Precision weight balance and Rockwell hardness testing machine as shown in Figure 1; sintering temperature of B 4 C, SiC, and ZrO 2 nanoparticles of 2.5%, 5%, 7.5%, and 12.5% reinforcement and base metal matrix titanium with different weight percentages of 75%, 77.5%, 82.5%, 85%, and 100% material were investigated. Sample notation and composition were tabulated in Table 1, powder metallurgy based approaches are appealing for the fabrication of both whisker-and particle-reinforced MMCs due to their simplicity in comparison to alternative manufacturing processes and the ability to generate complex structures with high precision [43][44][45]. The sintering and pressing method, also known as pressureless sintering, is the most fundamental and costeffective traditional PM technology. The traditional PM processing approach is classified into three major steps: powder blending and mixing, cold compression, and sintering. Titanium and reinforcement of nanopowders of B 4 C, SiC, and ZrO 2 powders were mixed with different weight percentages to create this power blend using high-speed dry ball milling and was employed; a 50 Mpa hydraulic press, shaped the powder into solid objects and sintered at a capacity of 1700 • C in a box furnace with different sintering temperatures. Table 2 represents the experimental procedure of Titanium MMM synthesized Sintered specimens having an average diameter of 20.0 mm and heights of 7 mm. The microstructure of the specimens was examined through scanning electron microscopy using the Jeol Japan SEM, Model JCM/6000PLUS BENCH TOP SEM, Musashino, Akishima, Tokyo 196-8558, JAPAN. A Shimadzu Corporation XRD-7000 Maxima X-ray diffractometer has also been used to analyze various phase compositions of the samples. A Digital Rockwell microhardness type HRS-150 was also utilized for microhardness measurement testing, Beijing United Tester Co., LTD of Beijing, China, and accomplished the examination with a weight of 150 kgf and a dwell time of 15 s. Figure 1 depicts the TMCs development and characterization flow chart. employed; a 50 Mpa hydraulic press, shaped the powder into solid objects and sintered at a capacity of 1700 °C in a box furnace with different sintering temperatures. Table 2 represents the experimental procedure of Titanium MMM synthesized Sintered specimens having an average diameter of 20.0 mm and heights of 7 mm. The microstructure of the specimens was examined through scanning electron microscopy using the Jeol Japan SEM, Model JCM/6000PLUS BENCH TOP SEM, Musashino, Akishima, Tokyo 196-8558, JAPAN. A Shimadzu Corporation XRD-7000 Maxima X-ray diffractometer has also been used to analyze various phase compositions of the samples. A Digital Rockwell microhardness type HRS-150 was also utilized for microhardness measurement testing, Beijing United Tester Co., LTD of Beijing, China, and accomplished the examination with a weight of 150 kgf and a dwell time of 15 s. Figure 1 depicts the TMCs development and characterization flow chart.    Powder metallurgy/PM/ is the best promising method for producing TMCs. Despite being a more expensive technique, it has the advantage of creating precision components without melting. The science of producing metal powders/particles and finished/semifinished items from mixed/alloyed powders with/without nonmetallic elements is known as powder metallurgy. Powder metallurgy consists of three distinct steps: (A) the combination of metal and reinforcing powders, (B) powder compaction/squeezing to form a green material body, and (C) sintering, which is frequently followed by additional processing.

Mixing or Blending and Sizing of Powders
Blending is the procedure of combining/unifying powders/particles that have different particle/powder sizes and shapes by passing them through the same simple mechanism. Blending should be used to achieve a consistent distribution of particle sizes and reduce porosity [46,47]. High-speed dry ball milling was used to grind/blend Ti, SiC, ZrO 2 , and B 4 C nanoparticle powders. The ball mill was outfitted with a high-speed spindle and ran for two hours to produce a homogeneous powder mixture. The powders were then obtained with the desired grain size and appropriate for the subsequent process. The weight, with the combined total of the powders, is 5 gm. Because these Nano-particles were a uniform particle size of 100 m, a powder-to-ball weight of 1:5 is ideal for successful mixing and sizing for 2 h. The milled powder results of ten (10) samples of Ti-based reinforced composites were synthesized using a high-speed dry ball milling machine.

Compaction
Utilizing a proper punch and die to generate green compacts using mechanical or hydraulic presses [46], powder mixtures are widely compacted. The powder combinations were cold crushing, squeezing, and compacting at an appropriate pressure with the use of a uniaxial press [48]. Compaction has been stated as the development of procedures, systems, and methods occurring in compacting and squeezing metallic particles in a hydraulically driven due to the required shape. These hydraulic presses have an owing capacity of 25 tons, a 200 mm diameter pressure plate, and a 150 mm ram stroke. To produce the specimen, milled metallic and ceramic powders are introduced into the die's cavity. For 30 min, all prepared samples are compressed at 50 MPa. After being formed at room temperature, the product is a specimen discharged from the die cavity at room temperature. In this experiment, hydraulic press samples were used to condense the milling power. Following the completion with a hydraulic cylindrical compression lower type bucket elevator and a green compacted sample shape, the cylindrical shaped specimens were visible.

Sintering
Sintering is defined as the procedure, method, and system for binding particles together by heating green compacts in a controlled environment. To sinter materials below their melting points, mesh belts, walking beams, pusher types, and batch furnaces are all used [46]. Many researchers assert that the highest sintering temperature is used to produce components with good surface finish and quality, and it has been demonstrated that as the sintering temperature rises, so do the material's mechanical properties [49,50]. The titanium sintering process was kept at a temperature ranging from 750 to 1350 • C, according to [51,52]. Powder metallurgy operates in the solid state below the melting point in a material with a ratio greater than 0.5 times the melting temperature and less than 0.8 times the melting temperature. Sintering is the compacting and formation of sample solids through heating in a vacuum furnace. The compression rates for samples one through ten sintered in a vacuum box furnace for 2 h at room temperature were 900 • C, 950 • C, 1000 • C, 1050 • C, 1100 • C,1150 • C,1200 • C,1250 • C,1300 • C, and 1350 • C, respectively.

Results and Discussion
The effect of various sintering temperatures, reinforcement particle size distribution, the dependence of mechanical properties, and strengthening mechanisms in B 4 C, SiC, and ZrO 2 reinforced titanium metal matrix composites of synthesized TMC material armored with B 4 C, SiC, and ZrO 2 through powder metallurgy techniques and various characterization was experimentally examined. Manufactured TMCs specimens were developed according to the selected parameters. The experiment's design was utilized to determine the optimal sintering temperature, compaction parameters, mixing parameters, and reinforcement particle size distribution that had the most influence on the mechanical and physical properties of the fabricated TMCs.

Characterization of the Synthesized TMCs
The surface topography of the synthesized specimen was investigated using SEM scanning to indicate the SEM microstructure of the synthesized TMMC along with base-Ti6Al4V specimens having a coarse lamellar + microstructure with phase separation created during sintering at high temperature and a subsequent slow cooling rate [5]. The Figure 2 shows the SEM micrographs of the samples. It has been observed from SEM micrographs that (2.5% B4C, 7.5% SiC, 12.5% ZrO2, 77.5% Ti) by increasing the concentrations of ZrO2 and decreasing B4C and SiC particles in sample S3, the porosity decreased and the surface densified in the Ti-based metal matrix. In most places on the surface of the Ti-based metal matrix sample S3, the ZrO2 particle agglomeration is seen. Because increasing the ZrO2 particle caused agglomeration Muharrem Pul et al. [53]. The addition of ZrO2 particles in the metal matrix composite initiated agglomeration. The microstructure of S3 shows that there is no porous structure between the 77.5%Ti and 2.5% B4C; 7.5% SiC and 12.5% ZrO2 reinforcing particles and the bonding of the phases are very good. We observed that samples S6 and S7 have the same concentrations of ZrO2 as S3, however, due to the increasing concentrations of B4C and SiC, S6 and S7 are more porous microstructures. Harish et al. [54] report that the porosity of the metal matrix composite materials in the microstructure increases with the increase in the particles of reinforcing. Therefore, with the same concentration of ZrO2 and different concentrations of B4C and SiC, samples S3, S6, and S7 have different surface morphologies. It has been observed from SEM micrographs that (2.5% B4C, 7.5% SiC, 12.5% ZrO 2 , 77.5% Ti) by increasing the concentrations of ZrO 2 and decreasing B 4 C and SiC particles in sample S3, the porosity decreased and the surface densified in the Ti-based metal matrix. In most places on the surface of the Ti-based metal matrix sample S3, the ZrO 2 particle agglomeration is seen. Because increasing the ZrO 2 particle caused agglomeration Muharrem Pul et al. [53]. The addition of ZrO 2 particles in the metal matrix composite initiated agglomeration. The microstructure of S3 shows that there is no porous structure between the 77.5%Ti and 2.5% B 4 C; 7.5% SiC and 12.5% ZrO 2 reinforcing particles and the bonding of the phases are very good. We observed that samples S6 and S7 have the same concentrations of ZrO 2 as S3, however, due to the increasing concentrations of B 4 C and SiC, S6 and S7 are more porous microstructures. Harish et al. [54] report that the porosity of the metal matrix composite materials in the microstructure increases with the increase in the particles of reinforcing. Therefore, with the same concentration of ZrO 2 and different concentrations of B 4 C and SiC, samples S3, S6, and S7 have different surface morphologies.

XRD Analysis
The elemental phases present in the manufactured samples were analyzed using XRD in accordance with the XRD working principle: Bragg's law [55] the XRD was performed on a fully computerized powder X-ray diffractometer (XRD7000 X-ray DIFFRACTOMETER, SHIMADZU Corporation (Tokyo, Japan)) at 40KV and 30mA. The XRD spectrum was generated at a two-degree angle ranging from 10 to 85 degrees with a 0.02-degree step size and continuous scanning at three degrees per minute for 0.40 s. Miller indices (hkl) are used to identify various planes of atoms, and the observed diffraction peaks can be related to the planes of atoms to aid in atomic structure and microstructure analysis. When analyzing XRD data, we look for trends that correspond to crystal structure directionality by analyzing the Miller indices of diffraction peaks. The crystal structure determines the position and intensity of peaks in a diffraction pattern. The fabricated samples were subjected to XRD analysis to determine whether any intermetallic compounds were formed during the sintering process [56]. When the diffractometer is linked to the X'pert data collector software, d' values are displayed directly on the diffraction pattern. These d' values were then used to identify different phases using ASTM X-ray diffraction data cards. To confirm the presence of minor precipitate phases detected by the diffraction pattern, the d values for different phases were obtained using JCPDS cards included with the software and manually compared with the diffraction pattern of all samples [55]. Figure 3 represents the XRD graph of the titanium-based metal matrix composite powders with milling before compaction and sintering were performed. The graph shows that there is a dominance of the titanium matrix peaks, which ascribes that in the milling process there was an undesirable interfacial chemical reaction between the hybrid reinforcements and the matrix with less peak is detected with angles of 2θ = 27.60 and 54.480 corresponding to (110) and (211), respectively, and the rutile (TiO 2 ) (JCPDScard number: 021-1276) developed. As shown in Figure 3a,b, titanium with a hexagonal closed packed crystal structure with a = b = c = 1.587 and ∝ = β = γ = 90 with an experimental density of 4.6 g/cm 3 can be detected in the titanium metal matrix samples, regardless of whether it is before or after sintering. However, in the composite shown in Figure 3b Figures 5 and 6 shows comparison of actual density and density predictable by ule of mixture.

Surface Hardness Testing of TMCs
Rockwell hardness examinations are the most extensively used hardness measuring techniques in the manufacturing sector. Diamond indenters are used to achieve various Rockwell hardness scales currently specified in ISO 6508-1, the most important of which are HRC, HRA, and HRN. The problems in introducing assessment methods to the measuring capabilities of the hardness test machines demonstrate the industry's requirement for more accurate calibration techniques within Rockwell hardness investigation machines. The ASTM E18 and 28 standard testing procedures were used to determine the hardness number of the specimens using the Rockwell hardness tester scale as tabulated in Table 3. The indenter utilized was with 150 kg Brale. The load application time is 15 s [41]. Variation of Rockwell micro hardness is shown in Figure 4.

Surface Hardness Testing of TMCs
Rockwell hardness examinations are the most extensively used hardness measuring techniques in the manufacturing sector. Diamond indenters are used to achieve various Rockwell hardness scales currently specified in ISO 6508-1, the most important of which are HRC, HRA, and HRN. The problems in introducing assessment methods to the   Figure 4.   According to Table 4, samples W% reinforcement and base metal by the law of mixture: the lower the hardness created in sintered specimens, the lower the minimum sintering temperature/heat. As a result, factors, such as insufficient reinforcement, particle dispersion, clustering of reinforced particles, temperature mismatch between particles and matrix, and particle size discrepancies between matrixes and reinforcing phases all affect the hardness of such composites. Hardness is caused by thermal mismatch, but clustering and insufficient dispersion can result in a decrease in hardness. Table 4. Samples Wt. % reinforcement and base metal by law/rule/ of mixture [42].

Density and Porosity Measurement
According to the density of the reinforcing material, the phase and size of the combining components, and the process of manufacturing the composite material, the density can increase or decrease [57]. Archimedes' principle was used to estimate the bulk density, porosity, and water absorption of sintered samples. The specimen's sintered weight was first determined using a precision digital weighing balance (HR-250AZ, A&D Company Limited, Korea). The drop in density can be attributed to the reinforcing particles' decreased density and the creation of porosity [24]. The specimen was then immersed in 70 • C hot water for 2 h, and the soaked weight was calculated by ASTME Designations C20-00 and [24,37]. The extent to which the TMCs compacted and sintered was measured using a tumbler full of water into which the samples were suspended down inside the water.
Through the Archimedes principle, the weight of sintered, soaked, and submerged materials were examined following equation: [58] Bulk density = Sintered weight (gm) soaking weight(gm) -Suspension weight (gm) × ρw (1) × Density of water(ρw) (2) To analyze the generated nanocomposites, the genuine density of all sintered specimens was tested using the Archimedes method and a density measurement device with a precision digital weighing balance (HR-250AZ, A&D Company limited, Seoul, Korea). The theoretical density was then computed using Agarwal and Broutman's equation [59][60][61][62] given in Table 5, where Wf denotes the weight fraction of reinforcement, Wm is the weight fraction of Ti6Al4V, and denotes the theoretical density of the composite and represents the density of reinforcements in SiC (3.21 g/cm 3 ), B 4 C (2.52 g/cm 3 ), and ZrO 2 (5.68 g/cm 3 ); ρm represents the density of the Ti6Al4V matrix (4.43 g/cm 3 ). The variation in the bulk density was then computed as illustrated in Figure 5. The high relative density of the sintered specimens implies that the constituent particles have strong interface bonding with negligible porosity or voids.      Therefore, the Bulk Density of TMC achieved a lower density of 2.5% B 4 C, 7.5% SiC, 12.5% ZrO 2 , and 77.5% Ti composition and developed a minimum density of 2.33 g/cm 3 and a 24% up to 47% reduced density according to the law of mixture. Additionally, an average reduction of 38% density in the synthesized TMC weight in the final product. Then, the Actual Density of TMC achieved a lower density of 7.5% B 4 C, 7.5% SiC, 2.5% ZrO 2 , and 82.5%Ti composition and developed a minimum density of 2.47 g/cm 3 and a 16% up to 44% reduced density according to the law of mixture. Additionally, there was an average reduction of 32% density in the synthesized TMC weight in the final product. Therefore, the Theoretical Density of TMC achieved a lower density of 5% B 4 C, 5% SiC, 5% ZrO 2 , and 85% Ti composition and developed a minimum density value of 0.7 g/cm 3 and a total of 79% up to 85% reduction in density according to the law of mixture. Additionally, there was an average reduction of 72% density in the synthesized TMC weight in the final product. Then, the relative density was calculated by the ratio of the actual density to the theoretical/calculated density. The high relative density of the sintered specimens indicates the strong interface bonding between the constituent particles with negligible porosity or cavities and the synthesized TMC of composite 5% B 4 C, 5% SiC, 5% ZrO 2 , 85% Ti with a rating of 5.17 gm/cm 3 .
As a result shown on Figure 5, the density weight percentage of the synthesized TMC was significantly reduced, and the weight of the material was also significantly reduced, making the developed material light. The purpose of facilitating weight reduction is the reinforcement in low density engineering materials. Due to this reason, the result, TMC's actual density was reduced. According to the law of mixture shown on Figure 6, 7.5% B4C, 7.5% SiC, 2.5% ZrO 2 , and 82.5%Ti have developed a minimum density of 2.47 g/cm 3 and a total density reduction of 16 percent to 44 percent. Additionally, the average density of synthesized TMC weight of the final product is reduced by 32%.

Porosity Measurement
The Archimedes concept was rummage-sale to compute the extent of porosity in TMCs sintered at different temperatures. Sintered dry weight/weight in air (Wd) was measured using a precision balance for each sintered Tmc sample. After that, the fabricated samples were immersed in water and boiled for two hours before being soaked for another 24 h. Suspension weight in water (Ww) of TMC samples was determined. The fabricated sample was soaked and the weight was measured when the water is removed by using dry tissue paper to remove excess water (Ws). The porosity was measured in accordance with Archimedes and determined by calculating using the equation [58]: where: ϕ = porosity (%), Ws = mass of the sample after soaking in distilled water for 24 h (g), Wd = mass of sintered dried sample (g), Ww = mass of sample hanging or suspension in water (g). According to [1], the porosity from theoretical density Equation (4) is being used to evaluate the actual density of each material; hence, Equation (4) is applied to compute the porosity of each material and the accurate porosity is calculated. Variation of Porosity calculated by Archimedes' principles as given in Equation (5) where P represents the porosity occurring in the material, ρa represents its actual density and ρt represents its theoretical density. The void content volume was then computed using Agarwal and Broutman's equation [59,60]. Figure 7 below depicts the porosity of the fabricated samples.
Porosity was calculated using Archimedes' principles with the minimum porosity of 2.34% has been observed for sample having composition of 7.5%, B 4 C, 7.5%, SiC, 2.5%, ZrO 2 , and 82.5%, Ti and the maximum porosity of 19.5% has been observed for the sample having composition of 5% B 4 C, 5% SiC, 5% ZrO 2 , 85% Ti. For the porosity calculation, the minimum porosity was computed using the theoretical density method rather than calculating porosity by the Archimedes principle. The void content of the synthesized TMC in nine samples was below one; this is indicated that the synthesized TMC are good consolidated engineering materials for the application of automotive and aerospace engineering. The high relative density of the sintered specimens indicates the strong interface bonding between the constituent particles with negligible porosity or cavities. P = 1 − ρt ρa (5) where P represents the porosity occurring in the material, ρa represents its actual density and ρt represents its theoretical density. The void content volume was then computed using Agarwal and Broutman's equation [59,60]. Figure 7 below depicts the porosity of the fabricated samples.

Estimate the Yield and Tensile Strengths
Since the invention of delamination hardness testing, there have been analyses to approximate other mechanical characteristics from bulk hardness measurements, particularly ultimate tensile strength and yield strength [63]. Hardness analyses have been widely used as a forecasting tool for estimating the yield and tensile strengths of Ni, Fe, Cu, and Al-based alloy systems [13,29,35,36,63,64], as well as nanocrystalline metal systems and metallic glasses, such as titanium [4,65]. Across these various metallic structures, there is an overall interaction for correlating the yield strength, y, and hardness H, σt = H 3 . This correlation is only acceptable for metallic materials with low strain hardening. If the material displays strain hardening, then the hardness estimation induces strain hardening, and the subsequent hardness assessment is representative of the strain-hardened material rather than the material prior to the measurement [66]. Theoretical equations were developed for equating the tensile and yield strengths to the hardness of metals that strain harden, such as steel, nickel, aluminum, and copper alloys [66]. It has been discovered that the strain induced by a Vickers indenter ranges between 8% and 10% and that the equivalent stress at this strain is approximately Hv/2.9 for steel and Hv/3 for copper alloys. If a metal has power-law strain hardening, the true stress, t, as a function of true strain, can be expressed as follows Et = KE n , where K is the material's strength coefficient and n is the strain hardening exponent, Tabor developed a relationship equating the tensile stress, UTS, to the Vickers hardness using the approximate stress observed for steels and copper alloys at a strain of 8%. Cahoon et al. [35] improved and simplified this relationship by doing the following, σUTS = Hv 2.9 n 0.217 n (6) It also discovered a link between the 0.2 percent offset yield strength, y, and the Vickers hardness for a metal with power-law strain hardening behavior. K can be calculated from Equation (3) by assuming that Hv/3 is the stress at a strain of 8%, and the yield strength to Vickers hardness relationship can be described as follows σy = Hv 3 Ey 0.08 n (7) where Ey denotes the true strain at 0.2% offset yield strength. Cahoon et al. [35] determined empirically that Ey was approximately 0.008 for both aluminum and steel samples. Using the following relationship [35], the yield strength can be equated to the Vickers hardness assuming that y can be treated as a constant for all metals However, the strain-hardening exponent, n, may not be known for a particular material, and obtaining n typically requires direct measurement through tensile testing. Thus, using these relationships as a predictive tool may not be practical for PM processes where the strain hardening behavior is not well characterized. Instead of relying on relationships empirically derived using n, a linear correlation between the strength and hardness can also be used as a predictive tool when the strain hardening behavior is unknown [29]. Despite varying strain hardening behaviors for various types of steels, the Vickers hardness still exhibits a strong linear correlation with the resulting tensile and yield strengths as can be seen from Table 6. However, the strain hardening does have an impact on the strength-to-hardness relationship, and the predicted strengths tend to be lower than the observed strengths for steels exhibiting a large amount of strain hardening [53,54,67]. For a given yield or tensile strength, the hardness values measured were higher than predicted by Equations (4) and (6) with n < 0.1. The data trend, however, seemed to follow a similar slope expected from the empirical models with n between 0.05 and 0.1 [68]. Currently, the only available strength-to-hardness correlation for Ti-6Al-4V is an empirical relationship, developed by [64,69] fitting of the Vickers hardness, Hv, and tensile strength, σUTS, for investment cast Ti-6Al-4V components. The tensile test is one of the most important mechanical property evaluation tests. Tensile tests are used for a variety of purposes. Tensile properties are frequently included in material specifications when selecting materials for engineering applications and ensuring quality. The strength of a material is frequently the most important factor to consider [70,71]. Although hardness is commonly used to predict strength in steel and other common alloy systems, titanium works similarly well while adhering to the ASTM standard. Variation of Approximation of computed hardness and tensile Strength is shown in Figure 8.

Conclusions
The use of TMC is increasing in not only the aerospace and automobile industries b also in marine, biomedical, electronic, chemical, and petrochemical industries. TMC w prepared by the metallurgical powdering technique, which was a low-cost efficie method. The different mechanical properties of the titanium composites were studied the reinforcement particles obtained in the composites with proper ratios. Both industr and academic researchers have displayed their interest in TMCs because it has be observed due to the following conclusions, that through the variation of sinteri temperature of TMC, the increasing sintering temperature caused the decrease in dens and porosity values. The TiO2 sample, which is sintered at over 900 °C tends to produc rutile phase. The addition of Boron carbide and silicon carbide in titanium at the ratio 2.5% to 12% of TMC has been found to reduce the density of the composite which w helpful to reduce the final product weight. The hardness of TMC showed the best resu when B4C, SiC, and ZrO2 were reinforced with 12% B4C, 12.5% SiC, 7.5% ZrO2, and 77.5 Ti and were a maximum of 59 in the Rockwell type "C" HRB scale. Hardness increas with the increase in B4C, SiC, and ZrO2 but decreases with the decreases in B4C, SiC, a ZrO2.To obtain optimum hardness, the reinforced material can be used in prop proportions and nanoparticles; this is the main result for achieving the best mechani properties. The reinforcing matrix element, which increased with SiC was found to very negligible in the pores when the mixture was conducted properly. Apart from t mechanical properties, the XRD pattern showed the matrix at different intensities whe

Conclusions
The use of TMC is increasing in not only the aerospace and automobile industries but also in marine, biomedical, electronic, chemical, and petrochemical industries. TMC was prepared by the metallurgical powdering technique, which was a low-cost efficient method. The different mechanical properties of the titanium composites were studied as the reinforcement particles obtained in the composites with proper ratios. Both industrial and academic researchers have displayed their interest in TMCs because it has been observed due to the following conclusions, that through the variation of sintering temperature of TMC, the increasing sintering temperature caused the decrease in density and porosity values. The TiO 2 sample, which is sintered at over 900 • C tends to produce a rutile phase. The addition of Boron carbide and silicon carbide in titanium at the ratio of 2.5% to 12% of TMC has been found to reduce the density of the composite which was helpful to reduce the final product weight. The hardness of TMC showed the best results when B 4 C, SiC, and ZrO 2 were reinforced with 12% B 4 C, 12.5% SiC, 7.5% ZrO 2 , and 77.5% Ti and were a maximum of 59 in the Rockwell type "C" HRB scale. Hardness increases with the increase in B 4 C, SiC, and ZrO 2 but decreases with the decreases in B 4 C, SiC, and ZrO 2 .To obtain optimum hardness, the reinforced material can be used in proper proportions and nanoparticles; this is the main result for achieving the best mechanical properties. The reinforcing matrix element, which increased with SiC was found to be very negligible in the pores when the mixture was conducted properly. Apart from the mechanical properties, the XRD pattern showed the matrix at different intensities where the interfacial bonding of the matrix directly affects the strength of the composite.