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Cross sectional electron probe micro analyzer (EPMA) analysis images after the wear test(same magnification): (a) room temperature, (b) 100 °C , (c) 200 °C , and (d) 300 °C .
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In this study, high volume fraction B4C reinforced Al matrix composites were fabricated with a liquid pressing process. Microstructural analysis by scanning electron microscope and a transmission electron microscopy shows a uniform distribution of the B4C reinforcement in the matrix, without any defects such as pore and unwanted reaction products....
Contexts in source publication
Context 1
... large debris and delamination area caused the rough surface, which accelerated the wear [25]. Figure 7 shows the cross-sectional EPMA analysis of the wear test specimen from room temperature to 300 °C . As confirmed from Figure 7, the wear of the composite with the breakage of the 40 µ m B4C particles occurred at room temperature and 100 °C due to the stress concentration. ...
Context 2
... 7 shows the cross-sectional EPMA analysis of the wear test specimen from room temperature to 300 °C . As confirmed from Figure 7, the wear of the composite with the breakage of the 40 µ m B4C particles occurred at room temperature and 100 °C due to the stress concentration. However, the fractured particles rarely detached, and they were physically well bonded with the matrix which is in accordance with the compressive test results. ...
Context 3
... the fractured particles rarely detached, and they were physically well bonded with the matrix which is in accordance with the compressive test results. As the temperature was increased over 200 °C (Figure 7c,d), cracks in the matrix occurred, and broken particles were released from the matrix. As the wear progressed, the debris became finer, and the counterpart material and matrix were abraded together, and they reacted with oxygen to form a new layer on the surface. ...
Context 4
... MML is an oxide layer that is brittle and hard; thus, the MML could improve the wear resistance. However, the MML was not observed in Figure 7a,b. This is because the large B4C particles were placed on the worn surface of the AMCs; thus, the surface could not form the oxide layer. ...
Context 5
... MML formed with a thickness of about 5 µ m at 200 °C, and the thickness of the MML was approximately 13 µ m at 300 °C. From Figure 7, it can be seen that the wear depth of the composite did not increase exponentially at the higher temperatures. Thus, we can have deduced that the formation of the MML at a temperature over 200 °C could improve the wear resistance of the composite [30,31]. ...
Context 6
... we can have deduced that the formation of the MML at a temperature over 200 °C could improve the wear resistance of the composite [30,31]. Figure 7 shows the cross-sectional EPMA analysis of the wear test specimen from room temperature to 300 • C. As confirmed from Figure 7, the wear of the composite with the breakage of the 40 µm B 4 C particles occurred at room temperature and 100 • C due to the stress concentration. However, the fractured particles rarely detached, and they were physically well bonded with the matrix which is in accordance with the compressive test results. ...
Context 7
... we can have deduced that the formation of the MML at a temperature over 200 °C could improve the wear resistance of the composite [30,31]. Figure 7 shows the cross-sectional EPMA analysis of the wear test specimen from room temperature to 300 • C. As confirmed from Figure 7, the wear of the composite with the breakage of the 40 µm B 4 C particles occurred at room temperature and 100 • C due to the stress concentration. However, the fractured particles rarely detached, and they were physically well bonded with the matrix which is in accordance with the compressive test results. ...
Context 8
... the fractured particles rarely detached, and they were physically well bonded with the matrix which is in accordance with the compressive test results. As the temperature was increased over 200 • C (Figure 7c,d), cracks in the matrix occurred, and broken particles were released from the matrix. As the wear progressed, the debris became finer, and the counterpart material and matrix were abraded together, and they reacted with oxygen to form a new layer on the surface. ...
Context 9
... MML is an oxide layer that is brittle and hard; thus, the MML could improve the wear resistance. However, the MML was not observed in Figure 7a,b. This is because the large B 4 C particles were placed on the worn surface of the AMCs; thus, the surface could not form the oxide layer. ...
Context 10
... Al7075 and iron that were oxidized were distributed on the surface, and the MML started to form reacting with the oxygen. The MML formed with a thickness of about 5 µm at 200 • C, and the thickness of the MML was approximately 13 µm at 300 • C. From Figure 7, it can be seen that the wear depth of the composite did not increase exponentially at the higher temperatures. Thus, we can have deduced that the formation of the MML at a temperature over 200 • C could improve the wear resistance of the composite [30,31]. ...
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... Based on the previous analysis, it is found that the matrix of composites containing B 4 C particles with sizes of 0.2 µm and 0.5 µm mainly consisted of AlB 2 and Al 3 BC phases. The existence of numerous brittle ceramic particles in the interior of B 4 C/Al composites results in a higher susceptibility to stress concentration, leading to macroscopic crack propagation dominated by brittle rupture of the ceramic phase, ultimately causing specimen failure under low stress conditions; the aforementioned findings are in line with the outcomes reported in the literature [37]. ...
... with sizes of 0.2 µm and 0.5 µm mainly consisted of AlB2 and Al3BC phases. The existence of numerous brittle ceramic particles in the interior of B4C/Al composites results in a higher susceptibility to stress concentration, leading to macroscopic crack propagation dominated by brittle rupture of the ceramic phase, ultimately causing specimen failure under low stress conditions; the aforementioned findings are in line with the outcomes reported in the literature [37]. In Figure 6e,f, as the particle size of B4C increases to 1 µm, the ductile fracture characteristics of the fracture morphology are more obvious. ...
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