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Article

Preparation of B4Cp/Al Composites via Selective Laser Melting and Their Tribological Properties

1
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China
2
Henan Key Laboratory of High Temperature Functional Ceramics, Zhengzhou University, Zhengzhou 450052, China
3
Department of Metallurgy and Materials Engineering, Yildiz Technical University, Istanbul 34349, Turkey
4
College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF, UK
*
Authors to whom correspondence should be addressed.
These authors contributed equally to this work.
Materials 2022, 15(23), 8340; https://doi.org/10.3390/ma15238340
Submission received: 2 November 2022 / Revised: 19 November 2022 / Accepted: 21 November 2022 / Published: 23 November 2022

Abstract

:
B4C-particle-reinforced Al (B4Cp/Al) composites are widely used in various areas, e.g., armors, electronic packaging and fuel storage, owing to their several outstanding properties including high specific rigidity, excellent wear resistance and light weight. Selective laser melting (SLM) is favored in manufacturing complex components because of its high raw material utilization rate and high efficiency. In this work, a B4Cp/Al composite was successfully synthesized by SLM, and the effects of one of the most important parameters, scanning speed (100–700 mm/s), on the phase composition, density, microhardness and tribological properties of the samples were investigated. The microhardness, relative density and dry-sliding wear resistance of as-prepared B4Cp/Al composites were improved with the decrease in scanning speed, and the sample fabricated at a scanning speed of 100 mm/s exhibited a relative density as high as about 97.1%, and a maximum microhardness of ~180 HV0.1 (approximately six times more than that of the SLM-formed pure Al sample, 31 HV0.1), a minimum wear rate of 4.2 × 10−5 mm3·N−1·m−1 and a corresponding friction coefficient of 0.41. In addition, abrasive wear, adhesive wear and oxidation wear were found to be behind the overall wear behavior of as-prepared B4Cp/Al composites.

1. Introduction

B4C particles are often used as reinforcements to prepare various composites because of their excellent physical and chemical properties including high hardness, good wear resistance and strong chemical stability [1,2]. Because of their high specific stiffness, light weight, good toughness and plasticity, good corrosion resistance and excellent wear resistance [3], B4Cp/Al composites have attracted much attention from researchers and been successfully used for vehicle and body armors, aerospace structures, electronic packaging, fuel storage and nuclear radiation protection [4]. To fabricate such composites of high quality, various methods including stir-casting, squeeze-casting, pressureless infiltration and ultrasound-assisted casting have been employed [5,6,7,8,9,10]. However, they suffer from various drawbacks such as severe phase segregation, poor interfacial bonding, high cost, low efficiency and difficulty in manufacturing a component of a complex geometry.
As a major additive manufacturing technique, selective laser melting (SLM) features the direct fabrication of three-dimensional (3D) parts with complicated structures [11]. Compared with the conventional manufacturing methods listed above, SLM used in preparing B4Cp/Al composites with complex structures shows many advantages including high precision, high utilization rate of raw materials, high applicability and remarkable mechanical properties of the manufactured products [12]. It was adopted in the preparation of various metal and alloy materials, for example titanium-, nickel- [13], iron- [14] and aluminum-based [15] materials for aerospace, automotive, military, nuclear power, shipbuilding and medical applications. For instance, the yield strength and tensile strength of Al-12Si alloys fabricated by SLM reached 260 MPa and 380 MPa, respectively, which were four times and twice as high, respectively, as that of their counterparts prepared by a casting method [16], and Al2O3/Al composites prepared by SLM exhibited a continuous and compatible interface between the Al2O3 and Al matrix and showed very high hardness and wear performances [17].
The laser scanning speed [18] has been proven to be important in the SLM preparation of composite materials. Ni et al. [19] fabricated 316L stainless steel via SLM and discussed the effect of the scanning speed on its corrosion resistance. They found that the number of voids and corrosion increased with increasing the scanning speed. Lu et al. [20] reported that the density, yield strength and corrosion resistance of SLM-fabricated Ni-free CoCrW materials were mainly determined by the laser scanning speed. Matras et al. [21] pointed out that an increase in the laser scanning speed caused deterioration to a certain extent in the surface roughness of SLM-manufactured AlSi10Mg semi-finished parts. Sadali et al. [22] observed that micro-cracks increased in as-prepared Ti6Al4V parts with the scanning speed, reducing the splashing effect of raw materials during SLM.
Based on the above discussions, in the present work, B4Cp/Al composites were further fabricated by SLM, and the effects of the scanning speed on their density, phase composition, microstructure, interfacial bonding, microhardness and tribological properties were examined in detail.

2. Experimental Procedure

2.1. Raw Material Powder

Spherical Al powder (purity 99.3%, mean diameter of 33 μm, Figure 1a) and angular B4C particles (purity 99.8%, average size of 65 μm, Figure 1b) were used as raw materials. They were mixed in a weight ratio of 4:1 for 12 h in a DECO-PM-2*5L ball mill with a rotating speed of 10 rpm and ball-to-powder weight ratio of 1:1.

2.2. SLM Processing

All the samples were fabricated on stainless steel substrates by a WJ SLM225 device with a YLR-500-WC-fiber laser under the protection of high-purity argon gas. To investigate the effect of the scanning speed on the preparation of B4Cp/Al composites, a series of samples with dimensions of 10 × 10 × 5 mm3 were prepared by using a laser beam of 1.07 μm in wavelength and 100 μm in spot size to scan the starting powders at different speeds (100, 300, 500 and 700 mm/s) while fixing the following processing parameters: 0.05 mm scanning distance, 0.05 mm layer thickness and 250 W laser power. A laser scanning mode with a rotation of 17° between neighboring layers was applied for minimizing the thermal stress formed during the SLM process, and the main processing parameters are listed in Table 1. The detailed SLM procedure has already been reported in our previous work, and is shown in Figure 2 [23].

2.3. Phase and Microstructure

The SLM-formed samples cut off from the substrates were ground and polished following the standard procedure and subjected to 40 s chemical etching with the Kroll’s reagent (95 vol.% of H2O, 1 vol.% of HF, 1.5 vol.% of HCl and 2.5 vol.% of HNO3) at room temperature prior to the following examination.
Phases of the samples were determined by X-ray diffraction (XRD, X’pert pro, Philips, The Netherlands) operating at 60 mA and 60 kV with Cu radiation (λ = 0.15406 nm). The theoretical density (DT) was calculated from the actual volume fraction of each phase, and the bulk density (DB) was measured by using the Archimedes’ method, from which the relative density (DR) of the samples was further calculated (DR = DB/DT). Phase morphologies and elemental compositions of the samples were examined on an FEI Nova NanoSEM 400 scanning electron microscope (SEM, FEI, Hillsboro, OR, USA) equipped with a Penta FET X-3 Si (Li) energy-dispersive spectrometer (EDS).

2.4. Mechanical Behaviour

Microhardness values of the samples were determined on a Vickers hardness tester (SH-318-III equipment) under a 100 g load for 10 s from multiple points on their cross section, and the average was recorded. The wear behavior and friction at room temperature were examined by a UMT-2 machine and wear-testing machine via the reciprocating test of ball-on-flat under the following conditions: dry friction, 20 N normal load, 5 mm/s friction speed, 6 mm friction stroke and 20 min duration. Carbon steel balls (HRC62) of 2 mm in diameter were used for the linear reciprocating motion. Each sample was tested three times under identical conditions, and the average values of the friction coefficient and wear rate were calculated.

3. Results and Discussion

Shown in Figure 3a are the XRD patterns of the B4Cp/Al composite samples prepared with various scanning speeds, revealing the coexistence of Al and B4C in them. Apart from these, Al4C3 and AlB2 were detected in all the cases, suggesting the in situ reaction between the Al melt and B4C. AlB2 and Al4C3 can be formed at 898–963 K and 1423–1458 K, respectively, via the reaction of B4C with Al melt [24], implying that the temperature of the mixed powders during the SLM process reached above 1423 K. The diffraction peak of the B4C phase at 2θ = 23.66° (Figure 3b) increased with the laser scanning speed, since a lower scanning speed provided a higher bulk energy density, favoring the increase in the molten pool temperature and thus promoting the reaction between the Al melt and B4C [23,25]. Figure 3c illustrates that the {111} diffraction peak of Al shifted to the right with respect to that of the starting Al powder, demonstrating that certain extents of lattice distortion occurred due to the laser-induced non-equilibrium [26]. Moreover, the intrinsic characteristic of the rapid heating/cooling rate during the SLM processing resulted in residual stress in the sample, which further intensified the lattice distortion [27].
Figure 4 and Figure 5 show the cross-sectional SEM images of B4Cp/Al composites prepared at different laser scanning speeds and their relative density values, respectively. When the laser power, layer thickness and hatch space were given, the increase in the laser scanning speed led to a decrease in the input energy, hindering the formation and fluidity increase of the Al melt. Since the temperature of the molten pool at a high laser scanning speed was low, “larger”-sized B4C particles were observed in the sample (Figure 4d, Table 2). Furthermore, the limited formation and low fluidity of the Al melt at a high laser scanning speed delayed the densification of the B4Cp/Al composites, resulting in more defects (pores and cracks) in them (Figure 4a–d). Correspondingly to Figure 4a–d, the density of the samples decreased from 97.1% to 85% when the scanning speed increased from 100 to 700 mm/s (Figure 5).
Similarly to the case of SiCp/Al composite preparation, the SLM process in the present case is also believed to be dominated by the complete melting–solidification mechanism [23]. Initially, a molten pool was formed under the laser irradiation. Then, the high temperature melt with good fluidity flowed around to fill various forms of voids, following which an in-situ reaction between the melt and nonmelted particles occurred. The temperature of the formed molten pool played a major role in the densification of the B4Cp/Al composite samples. Compared with B4Cp, Al has a much lower melting point and a stronger laser absorption ability [28]; therefore, the Al powders absorbed the laser energy and melted to form the molten pool. The temperature in the molten pool can be calculated by the following Equation (1) [29]:
Δ T m a x = 2   A   η ( k t h   τ p π ) / k
In Equation (1), A, η, kth, τp and k represent the laser absorptivity, volume energy density, heat diffusivity, time duration and thermal conductivity, respectively. After these parameters are determined, the temperature change (ΔTmax) in the laser-induced molten pool can be calculated according to Equation (1). ΔTmax is directly proportional to the energy density (η), which is determined by the following Equation (2) [30]:
η = P/(vhd)
where P represents the laser power, v the scanning speed, h the hatch space and d the layer thickness.
According to Equation (2), the energy density is inversely proportional to the scanning speed. When other processing parameters are given, as indicated by Equations (1) and (2), a high energy density arising from a low scanning speed led to an increase in the temperature of the powder bed, facilitating the formation of a liquid phase and the subsequent densification of the samples.
Presented in Figure 6 are SEM images of representative interfaces between B4C particles and the Al matrix in the B4Cp/Al composites fabricated at different scanning speeds. In the case of using a low scanning speed, the B4C particles were in close contact with the surrounding Al matrix, and less defects were present at their interface (Figure 6a–b). On the other hand, in the case of using a high scanning speed, some pores and micro-cracks were seen at the interface (Figure 6c–d). Strong interfacial bonding was beneficial to the enhancement of the physical properties of the as-fabricated composite samples [31,32].
Figure 7 gives microhardness values of the B4Cp/Al composite and Al alloy samples prepared via SLM, revealing the negative effect of the high scanning speed on the microhardness. With the increase in the scanning speed from 100 to 700 mm/s, the microhardness of the composite samples decreased from 180 HV0.1 to 129 HV0.1. This was because with decreasing the scanning speed, the relative density of the samples increased (Figure 5) and their defects (pores and micro-cracks) decreased. Surprisingly, the maximum microhardness value of the as-formed B4Cp/Al composite samples (180 HV0.1) was about six times as high as that of the Al alloy sample (31 HV0.1), demonstrating the great effect of B4C particle reinforcement on the microhardness of the Al matrix. Similar effects were also found in the cases of SiCp/Al [23,33], (TiC + TiB2)/Al [34], SiCp/A365 [35] and TiC/Ni [36] composites prepared via SLM.
Figure 8 shows low- and high-magnification SEM images of wear surfaces of the B4Cp/Al samples corresponding to different scanning speeds. At a scanning speed as low as 100 mm/s, only shallow furrows with rough edges were observed on the worn surface (Figure 8a), indicating that the abrasive wear mechanism dominated the wear process of the B4Cp/Al composite sample. At a higher scanning speed of 300 mm/s, a few abrasive particles besides furrows were adhered to the worn surface (Figure 8b), indicating the dominance of the abrasive–adhesion wear mechanism. On increasing the scanning speed to 500 mm/s, some peeling-off debris and deeper furrows were observed (Figure 8c), revealing the dominance of the adhesive wear mechanism. On further increasing the scanning speed to 700 mm/s, the peeling-off, as expected, resulted in lots of wear debris (Figure 8d), confirming the governing of the adhesive wear mechanism. Overall, more defects including furrows, abrasive particles and debris were formed on the worn surface as the scanning speed increased, which was due to the reduced densification and weakened interfacial bonding between B4C particles and the Al matrix of the composite samples [23].
To further explore the wear mechanism of the as-fabricated B4Cp/Al composites, the worn surface was additionally examined by high-magnification SEM. As presented in Figure 9, not only Al, C and B elements but also O and Fe elements were detected on the worn surface of the sample fabricated at a scanning speed of 100 mm/s, suggesting the occurrence of additional oxidative wear, and tribo-oxides generally play a positive role in reducing the wear [37]. The presence of Fe implied a possible change in the grinding medium (HRC62 carbon-steel balls). For the other composite samples prepared under higher scanning speeds, the element distributions were similar (no further description here to avoid repetition).
Figure 10 demonstrates the relationships between the laser scanning speed, the wear rate of the B4Cp/Al sample and the corresponding friction coefficient, revealing that the latter two increased with increasing the first one. As the scanning speed increased from 100 mm/s to 300, 500 and 700 mm/s, the friction coefficient was increased from 0.41 to 0.44, 0.47 and 0.51, respectively. Meanwhile, the wear rate was increased from 4.2 × 10−5 to 5.5 × 10−5, 7.8 × 10−5 and 9.5 × 10−5 mm3·N−1·m−1, respectively. These results could be attributed to the higher density, stronger interfacial bonding and higher microhardness of the samples prepared at a lower scanning speed (Figure 4, Figure 5, Figure 6 and Figure 7).
In addition to the samples described above, some representative components with complex geometries (Figure 11a,b) were successfully fabricated by SLM using B4C particles and Al powder as raw materials, further demonstrating the universal feasibility of the SLM technique in preparing an Al matrix of a complex structure. To compare, Table 3 lists the tribological and other mechanical properties of B4C-particle-reinforced Al matrix composites prepared by other methods, revealing the higher microhardness and superior tribological property of the B4Cp/Al composite samples prepared in the present work.

4. Conclusions

A B4Cp/Al composite with considerably improved mechanical properties was successfully prepared via SLM. The main conclusions are drawn as follows:
(1) The densification of the SLM-prepared B4Cp/Al composite samples decreased from 97.1% to 85% with increasing the scanning speed due to the decreased molten pool temperature, resulting in a weakened interfacial bonding between the B4C reinforcement phase and the Al matrix.
(2) The increase in the scanning speed showed negative effects on the tribological properties and microhardness of the B4Cp/Al composite samples due to the reduced relative density. The composite sample prepared with the lowest scanning speed exhibited the maximum microhardness of 180 HV0.1, minimum wear rate of 4.2 × 10–5 mm3·N−1·m−1 and a corresponding friction coefficient of 0.41. Encouragingly, the maximum microhardness of the B4Cp/Al composite sample prepared in this work was six times as high as that of the Al alloy counterpart.
(3) The wear mechanism of as-prepared B4Cp/Al samples changed from abrasive wear to adhesive wear with increasing the scanning speed. Additionally, oxidation wear was also involved in the wear process.

Author Contributions

Conceptualization, G.Y. (Guodong Yang) and J.Z. (Jialian Zhang); data curation, H.X.; formal analysis, Q.J.; funding acquisition, H.Z.; investigation, G.Y. (Gaoqian Yuan); methodology, H.X.; resources, J.Z. (Jingzhe Zhang); software, H.X.; supervision, F.L. and H.Z.; validation, F.L., H.Z. and S.Z.; visualization, Z.H.; writing—original draft, G.Y. (Guodong Yang) and J.Z. (Jialian Zhang); writing—review & editing, F.L., H.Z., H.A.Y. and S.Z. All authors have read and agreed to the published version of the manuscript.

Funding

This work was funded by National Natural Science Foundation of China (Grant No 52072274 and 51872210) and the Program for Innovative Teams of Outstanding Young and Middle-aged Researchers in the Higher Education Institutions of Hubei Province (T201602).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available from the corresponding authors upon reasonable request.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Najafi, A.; Golestani-Fard, F.; Rezaie, H.R. Sol-gel synthesis and characterization of B4C nanopowder. Ceram. Int. 2018, 44, 21386–21394. [Google Scholar] [CrossRef]
  2. Najafi, A.; Golestani-Fard, F.; Rezaie, H.R.; Saeb, S.P. Sol-Gel synthesis and characterization of SiC–B4C nano powder. Ceram. Int. 2021, 47, 6376–6387. [Google Scholar] [CrossRef]
  3. Singh, J.; Chauhan, A. Characterization of hybrid aluminum matrix composites for advanced applications—A review. J. Mater. Res. Technol. 2016, 5, 159–169. [Google Scholar] [CrossRef] [Green Version]
  4. Wu, H.B.; Zeng, F.H.; Yuan, T.; Zhang, F.Q.; Xiong, X. Wettability of 2519Al on B4C at 1000–1250 °C and mechanical properties of infiltrated B4C–2519Al composites. Ceram. Int. 2014, 40, 2073–2081. [Google Scholar] [CrossRef]
  5. Auradi, V.; Rajesh, G.L.; Kori, S.A. Preparation and evaluation of mechanical properties of 6061Al–B4Cp composites produced via two-stage melt stirring. Adv. Manuf. Process. 2014, 29, 194–200. [Google Scholar] [CrossRef]
  6. Chen, M.; Liu, Z. Ultrasound assisted casting method for fabricating B4Cp/Al composites with the addition of K2ZrF6. Mater. Lett. 2020, 280, 128545. [Google Scholar] [CrossRef]
  7. Karabulut, Y.; Ünal, R. Additive manufacturing of ceramic particle-reinforced aluminum-based metal matrix composites: A review. J. Mater. Sci. 2022, 57, 19212–19242. [Google Scholar] [CrossRef]
  8. Li, W.; Yang, Y.; Liu, J.; Zhou, Y.; Li, M.; Wen, S.F.; Wei, Q.S.; Yan, C.Z.; Shi, Y.S. Enhanced nanohardness and new insights into texture evolution and phase transformation of TiAl/TiB2 in-situ metal matrix composites prepared via selective laser melting. Acta. Mater. 2017, 136, 90–104. [Google Scholar] [CrossRef]
  9. Xi, L.; Wang, P.; Prashanth, K.G.; Li, H.; Prykhodko, H.V.; Scudino, S.; Kaban, I. Effect of TiB2 particles on microstructure and crystallographic texture of Al-12Si fabricated by selective laser melting. J. Alloys Compd. 2019, 786, 551–556. [Google Scholar] [CrossRef]
  10. Dan, C.Y.; Chen, Z.; Mathon, M.H.; Ji, G.; Li, L.W.; Wu, Y.; Brisset, F.; Guo, L.; Wang, H.W.; Ji, V. Cold rolling texture evolution of TiB2 particle reinforced Al-based composites by Neutron Diffraction and EBSD analysis. Mater. Charact. 2018, 136, 293–301. [Google Scholar] [CrossRef]
  11. Attar, H.; Bönisch, M.; Calin, M.; Zhang, L.C.; Scudino, S.; Eckert, J. Selective laser melting of in situ titanium–titanium boride composites: Processing, microstructure and mechanical properties. Acta Mater. 2014, 76, 13–22. [Google Scholar] [CrossRef]
  12. Almangour, B.; Baek, M.S.; Grzesiak, D.; Lee, K.A. Strengthening of stainless steel by titanium carbide addition and grain refinement during selective laser melting. Mater. Sci. Eng. A 2018, 712, 812–818. [Google Scholar] [CrossRef]
  13. Li, W.; Sun, R.; Wang, P.; Li, X.L.; Sakai, T. Subsurface faceted cracking behavior of selective laser melting Ni-based superalloy under very high cycle fatigue. Scr. Mater. 2021, 194, 113613. [Google Scholar] [CrossRef]
  14. Nong, X.D.; Zhou, X.L.; Ren, Y.X. Fabrication and characterization of Fe-based metallic glasses by selective laser melting. Opt. Laser Technol. 2019, 109, 20. [Google Scholar] [CrossRef]
  15. Lamagna, L.; Paiella, A.; Masi, S.; Bottini, L.; Boschetto, A.; Veniali, F. Selective laser melting process of Al–based pyramidal horns for the W-band: Fabrication and testing. J. Infrared Millim. Terahertz Waves 2021, 42, 154–172. [Google Scholar] [CrossRef]
  16. Prashanth, K.G.; Scudino, S.; Klauss, H.J.; Surreddi, K.B.; Lober, L.; Wang, Z.; Chaubey, A.K.; Kuhn, U.; Eckert, J. Microstructure and mechanical properties of Al–12Si produced by selective laser melting: Effect of heat treatment. Mater. Sci. Eng. A 2014, 590, 153–160. [Google Scholar] [CrossRef]
  17. Jue, J.; Gu, D.; Chang, K.; Dai, D. Microstructure evolution and mechanical properties of Al-Al2O3 composites fabricated by selective laser melting. Powder Technol. 2017, 310, 80–91. [Google Scholar] [CrossRef]
  18. Shang, Y.; Yuan, Y.; Li, D.; Li, Y.; Chen, J. Effects of scanning speed on in vitro biocompatibility of 316L stainless steel parts elaborated by selective laser melting. Int. J. Adv. Manuf. Technol. 2017, 92, 4379–4385. [Google Scholar] [CrossRef]
  19. Ni, X.; Kong, D.; Wu, W.; Liang, Z.; Dong, C.; He, B.; Lin, L.; Wu, K.; Zhu, D. Corrosion behavior of 316L stainless steel fabricated by selective laser melting under different scanning speeds. J. Mater. Eng. Perform. 2018, 27, 3667–3677. [Google Scholar] [CrossRef]
  20. Lu, Y.; Gan, Y.; Lin, J.; Guo, S.; Wu, S.; Lin, J. Effect of laser speeds on the mechanical property and corrosion resistance of CoCrW alloy fabricated by SLM. Rapid. Prototyp. J. 2017, 23, 28. [Google Scholar] [CrossRef]
  21. Matras, A. Research and optimization of surface roughness in milling of SLM semi-finished parts manufactured by using the different laser scanning speed. Materials 2020, 13, 9. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  22. Sadali, M.F.; Hassan, M.Z.; Ahmad, F.; Yahaya, H.; Rasid, Z.A. Influence of selective laser melting scanning speed parameter on the surface morphology, surface roughness, and micropores for manufactured Ti6Al4V parts. J. Mater. Res. 2020, 35, 2025–2035. [Google Scholar] [CrossRef]
  23. Xie, H.B.; Zhang, J.L.; Li, F.L.; Yuan, G.Q.; Zhu, Q.; Jia, Q.L.; Zhang, H.J.; Zhang, S.W. Selective laser melting of SiCp/Al composites: Densification, microstructure, and mechanical and tribological properties. Ceram. Int. 2021, 47, 30826–30837. [Google Scholar] [CrossRef]
  24. Viala, J.C.; Bouix, J.; Gonzalez, G.; Esnouf, C. Chemical reactivity of aluminium with boron carbide. J. Mater. Sci. 1997, 32, 4559–4573. [Google Scholar] [CrossRef]
  25. Tonelli, L.; Fortunato, A.; Ceschini, L. CoCr alloy processed by selective laser melting (SLM): Effect of laser energy density on microstructure, surface morphology, and hardness. J. Manuf. Process. 2020, 52, 106–119. [Google Scholar] [CrossRef]
  26. Fei, C.; Gu, D.; Dai, D.; Yuan, P. Selective laser melting of in-situ Al4SiC4 + SiC hybrid reinforced Al matrix composites: Influence of starting SiC particle size. Surf. Coat. Technol. 2015, 272, 15–24. [Google Scholar] [CrossRef]
  27. Almangour, B.; Grzesiak, D.; Yang, J.M. Selective laser melting of TiC reinforced 316L stainless steel matrix nanocomposites: Influence of starting TiC particle size and volume content. Mater. Des. 2016, 104, 141–151. [Google Scholar] [CrossRef]
  28. Anthes, J.P.; Palmer, M.A.; Gusinow, M.A.; Matzen, M.K. Absorption of laser radiation by Al, Fe, and Au planar metallic targets. Appl. Phys. Lett. 1979, 34, 841. [Google Scholar] [CrossRef]
  29. Fischer, P.; Romano, V.; Weber, H.P.; Karapatis, N.P.; Boillit, E.; Glardon, R. Sintering of commercially pure titanium powder with a Nd:YAG laser source. Acta Mater. 2003, 51, 1651–1662. [Google Scholar] [CrossRef]
  30. Thijs, L.; Verhaeghe, F.; Craeghs, T.; Humbeeck, J.V.; Kruth, J.P. A study of the microstructural evolution during selective laser melting of Ti–6Al–4V. Acta Mater. 2010, 58, 3303–3312. [Google Scholar] [CrossRef]
  31. Liao, Q.; Wei, W.; Zuo, H.; Li, X.; Wu, G. Interfacial bonding enhancement and properties improvement of carbon/copper composites based on nickel doping. Compos. Interfaces 2020, 28, 637–649. [Google Scholar] [CrossRef]
  32. Lee, D.; Kim, J.; Lee, S.K.; Kim, Y.; Cho, S. Experimental and thermodynamic study on interfacial reaction of B4C–Al6061 composites fabricated by stir casting process. J. Alloys Compd. 2020, 859, 157813. [Google Scholar] [CrossRef]
  33. El-Kady, O.; Fathy, A. Effect of SiC particle size on the physical and mechanical properties of extruded Al matrix nanocomposites. Mater. Des. 2014, 54, 348–353. [Google Scholar] [CrossRef]
  34. Yang, H.Y.; Wang, Z.; Chen, L.Y.; Shu, S.L.; Zhang, L.C. Interface formation and bonding control in high-volume-fraction (TiC+TiB2)/Al composites and their roles in enhancing properties. Compos. Part B Eng. 2021, 209, 108605. [Google Scholar] [CrossRef]
  35. Laorden, L.M.; Rodrigo, P.; Torres, B.; Rams, J. Modification of microstructure and superficial properties of A356 and A356/10%SiCp by selective laser surface melting (SLSM). Surf. Coat. Technol. 2017, 309, 1001–1009. [Google Scholar] [CrossRef]
  36. Wang, R.; Zhang, G.; Yang, C.; Zhou, W.; Sun, B. Novel selective laser melting processed in-situ TiC particle-reinforced Ni matrix composite with excellent processability and mechanical properties. Mater. Sci. Eng. A 2020, 797, 140145. [Google Scholar] [CrossRef]
  37. Wilson, S.; Alpas, A.T. Thermal effects on mild wear transitions in dry sliding of an aluminum alloy. Wear 1999, 225–229, 440–449. [Google Scholar] [CrossRef]
  38. Aleksander, J.P.; Beaman, D.R. Al-B-C phase development and effects on mechanical properties of B4C/Al-Derived composites. J. Am. Ceram. Soc. 1995, 78, 305–312. [Google Scholar] [CrossRef]
  39. Peng, Z.; Li, Y.; Wang, W.; Gao, Z.; Wang, B. The design, fabrication and properties of B4C/Al neutron absorbers. J. Nucl. Mater. 2013, 437, 350–358. [Google Scholar] [CrossRef]
  40. Chen, H.S.; Wang, W.X.; Li, Y.L.; Zhou, J.; Nie, H.H.; Wu, Q.C. The design, microstructure and mechanical properties of B4C/6061Al neutron absorber composites fabricated by SPS. Mater. Des. 2016, 94, 360–367. [Google Scholar] [CrossRef]
  41. Li, Y.Z.; Wang, Q.Z.; Wang, W.G.; Xiao, B.L.; Ma, Z.Y. Interfacial reaction mechanism between matrix and reinforcement in B4C/6061Al composites. Mater. Chem. Phys. 2015, 154, 107–117. [Google Scholar] [CrossRef]
  42. Baradeswaran, A.; Perumal, A.E. Influence of B4C on the tribological and mechanical properties of Al 7075–B4C composites. Compos. Part B Eng. 2013, 54, 146–152. [Google Scholar] [CrossRef]
  43. Lashgari, H.R.; Sufizadeh, A.R.; Emamy, M. The effect of strontium on the microstructure and wear properties of A356–10%B4C cast composites. Mater. Des. 2010, 31, 2187–2195. [Google Scholar] [CrossRef]
  44. Canakci, A. Microstructure and abrasive wear behaviour of B4C particle reinforced 2014 Al matrix composites. J. Mater. Sci. 2008, 46, 2805–2813. [Google Scholar] [CrossRef]
  45. Tang, F.; Wu, X.; Ge, S.; Ye, J.; Zhu, H.; Hagiwara, M.; Schoenung, J.M. Dry sliding friction and wear properties of B4C particulate-reinforced Al-5083 matrix composites. Wear 2008, 264, 555–561. [Google Scholar] [CrossRef]
  46. Mazaheri, Y.; Meratian, M.; Emadi, R.; Najarian, A.R. Comparison of microstructural and mechanical properties of Al–TiC, Al–B4C and Al–TiC–B4C composites prepared by casting techniques. Mater. Sci. Eng. A 2013, 560, 278–287. [Google Scholar] [CrossRef]
  47. Shorowordi, K.M.; Haseeb, A.S.M.A.; Celis, J.P. Tribo-surface characteristics of Al–B4C and Al–SiC composites worn under different contact pressures. Wear 2006, 261, 634–641. [Google Scholar] [CrossRef]
Figure 1. Microstructural images of the starting powders of Al (a) and B4C (b).
Figure 1. Microstructural images of the starting powders of Al (a) and B4C (b).
Materials 15 08340 g001
Figure 2. Flow chart of the overall experimental procedure.
Figure 2. Flow chart of the overall experimental procedure.
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Figure 3. XRD patterns of B4Cp/Al composites fabricated via SLM at different scanning speeds: (a) 2θ = 10–90°; (b) 2θ = 23–24°; (c) 2θ = 37–40°. (Al: ICCD 064700; B4C: ICCD 029093; Al4C3: ICCD 014397; AlB2: ICCD 043851).
Figure 3. XRD patterns of B4Cp/Al composites fabricated via SLM at different scanning speeds: (a) 2θ = 10–90°; (b) 2θ = 23–24°; (c) 2θ = 37–40°. (Al: ICCD 064700; B4C: ICCD 029093; Al4C3: ICCD 014397; AlB2: ICCD 043851).
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Figure 4. Cross-sectional SEM images of B4Cp/Al composite samples prepared at different laser scanning speeds: (a) 100 mm/s; (b) 300 mm/s; (c) 500 mm/s; (d) 700 mm/s.
Figure 4. Cross-sectional SEM images of B4Cp/Al composite samples prepared at different laser scanning speeds: (a) 100 mm/s; (b) 300 mm/s; (c) 500 mm/s; (d) 700 mm/s.
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Figure 5. Relative density values of B4Cp/Al composite samples as a function of laser scanning speed.
Figure 5. Relative density values of B4Cp/Al composite samples as a function of laser scanning speed.
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Figure 6. SEM images of B4Cp/Al composite samples fabricated via SLM at different scanning speeds: (a) 100 mm/s; (b) 300 mm/s; (c) 500 mm/s; (d) 700 mm/s. The images highlight the representative interfaces between B4Cp and Al.
Figure 6. SEM images of B4Cp/Al composite samples fabricated via SLM at different scanning speeds: (a) 100 mm/s; (b) 300 mm/s; (c) 500 mm/s; (d) 700 mm/s. The images highlight the representative interfaces between B4Cp and Al.
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Figure 7. Microhardness values of B4Cp/Al composite and Al alloy samples formed by SLM at different scanning speeds.
Figure 7. Microhardness values of B4Cp/Al composite and Al alloy samples formed by SLM at different scanning speeds.
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Figure 8. Low- (left column) and high-magnification (right column) SEM images of worn surfaces of SLM-prepared B4Cp/Al samples corresponding to different scanning speeds: (a,a1) 100 mm/s; (b,b1) 300 mm/s; (c,c1) 500 mm/s; (d,d1) 700 mm/s.
Figure 8. Low- (left column) and high-magnification (right column) SEM images of worn surfaces of SLM-prepared B4Cp/Al samples corresponding to different scanning speeds: (a,a1) 100 mm/s; (b,b1) 300 mm/s; (c,c1) 500 mm/s; (d,d1) 700 mm/s.
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Figure 9. EDS mappings of worn surface of the SLM-formed B4Cp/Al sample prepared at a scanning speed of 100 mm/s: (a) SEM image of examined area; and elemental distributions of (a-1) Al, (a-2) C, (a-3) B, (a-4) O and (a-5) Fe.
Figure 9. EDS mappings of worn surface of the SLM-formed B4Cp/Al sample prepared at a scanning speed of 100 mm/s: (a) SEM image of examined area; and elemental distributions of (a-1) Al, (a-2) C, (a-3) B, (a-4) O and (a-5) Fe.
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Figure 10. Effects of scanning speed on coefficients of friction (COF) (a) and wear rate (b) of B4Cp/Al samples.
Figure 10. Effects of scanning speed on coefficients of friction (COF) (a) and wear rate (b) of B4Cp/Al samples.
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Figure 11. Two representative components (a,b) with complex matrix structures fabricated by SLM.
Figure 11. Two representative components (a,b) with complex matrix structures fabricated by SLM.
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Table 1. SLM processing parameters.
Table 1. SLM processing parameters.
No.Laser Power
[W]
Scanning Speed [mm/s]Hatch Space
[mm]
Layer Thickness
[mm]
Energy Density [J/mm3]
12501000.050.051000
2300333
3500200
4700143
Table 2. EDS analysis of spots 1, 2 and 3 in Figure 4d.
Table 2. EDS analysis of spots 1, 2 and 3 in Figure 4d.
Spot No.Atomic Content/%
BCAlO
Spot 179.318.22.50
Spot 278.519.02.50
Spot 30089.110.9
Table 3. Tribological and other mechanical properties of B4C-particle-reinforced Al matrix composites reported previously.
Table 3. Tribological and other mechanical properties of B4C-particle-reinforced Al matrix composites reported previously.
MethodMatrixB4C FractionRelative
Density
HardnessWear RateFriction
Coefficient
Ref.
Post densification heat treatmentPure Al70 vol.%N/A81 HRAN/AN/A[38]
Hot-press infiltrate6061Al alloy30 wt.%98%123.6 HV0.5N/AN/A [39]
Spark plasma sintering6061Al alloy20 vol.%99.32%146 HV1N/AN/A[40]
Powder metallurgy technique6061Al alloy20 wt.%N/A40 HRBN/AN/A[41]
Casting techniqueAA7075 alloy10 vol.%N/A175 BHN7 × 10−6 g/m0.327[42]
Stir-casting techniqueA356 alloy10 vol.%N/AN/A2.1 × 10−3 mg/mN/A[43]
Stir-casting techniqueAA2014 alloy12 vol.%91.75%107 BHNN/AN/A[44]
Hot isostatic pressingAA5083 alloy10 wt.%N/AN/AN/A0.41[45]
Squeeze-casting techniquePure Al10 vol.%N/A51 ± 3 HV5N/A0.31[46]
Stir-casting techniquePure Al13 vol.%91.75%N/A4.23 × 10−4 mm3/mN/A[47]
SLMPure Al20 wt.%97.1%180 HV0.14.2 × 10−5 mm3/(N m)0.41This work
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Yang, G.; Zhang, J.; Xie, H.; Li, F.; Huang, Z.; Yuan, G.; Zhang, J.; Jia, Q.; Zhang, H.; Yeprem, H.A.; et al. Preparation of B4Cp/Al Composites via Selective Laser Melting and Their Tribological Properties. Materials 2022, 15, 8340. https://doi.org/10.3390/ma15238340

AMA Style

Yang G, Zhang J, Xie H, Li F, Huang Z, Yuan G, Zhang J, Jia Q, Zhang H, Yeprem HA, et al. Preparation of B4Cp/Al Composites via Selective Laser Melting and Their Tribological Properties. Materials. 2022; 15(23):8340. https://doi.org/10.3390/ma15238340

Chicago/Turabian Style

Yang, Guodong, Jialian Zhang, Houbo Xie, Faliang Li, Zhong Huang, Gaoqian Yuan, Jingzhe Zhang, Quanli Jia, Haijun Zhang, Hasibe Aygul Yeprem, and et al. 2022. "Preparation of B4Cp/Al Composites via Selective Laser Melting and Their Tribological Properties" Materials 15, no. 23: 8340. https://doi.org/10.3390/ma15238340

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