颗粒尺寸对B_4C增强铝基中子吸收材料界面反应与力学性能的影响

Effects of particle size on interfacial reaction and mechanical properties of B_4C reinforced aluminum matrix neutron absorber materials

采用粉末冶金真空热压法制备了B_4C质量分数为31%、平均颗粒尺寸分别为6.5μm、9.3μm、17.3μm、28μm、39.5μm的纯Al和6061Al基体的复合材料。对复合材料进行微观结构和力学性能检测,结果表明:所有复合材料的B_4C颗粒在基体中都均匀分布,且致密度都达到99%以上;对于纯Al基复合材料,随着颗粒尺寸增加,其致密度和塑性逐渐增加,强度逐渐下降;对于6061Al基复合材料,致密度随着颗粒尺寸的增加稍有降低,其强度和塑性受颗粒尺寸和热压温度共同影响,当热压温度610℃时,界面反应严重,随B_4C颗粒尺寸增加,强度先下降后上升,塑性先上升后下降;当热压温度580℃时,界面反应轻微,复合材料强度逐渐下降,塑性逐渐上升。颗粒尺寸、界面反应和基体材料等均影响B_4C增强铝基复合材料的力学性能。

The pure Al and 6061Al matrix composites with 31%B4C particle sizes of 6.5-39.5 μm were respectively prepared by powder metallurgy.The microstructure and mechanical properties of composites were tested.The results show that the B4C particles were uniformly distributed in the matrix of all composites,and the densities reached above 99%.For pure Al matrix composites,with the increase of particle size,the densities and ductility increase gradually,and the strength decreases gradually.For 6061Al matrix composites,the densities increase slightly with the increase of particle size,and its strength and ductility are affected by the particle size and the hot-pressing temperature.When hot-pressing temperature is 610℃,the interface reaction is serious.With the increase of B4C particle size,the strength decreases first and then increases,while the ductility increases first and then decreases.When hot-pressing temperature is 580℃,the interface reaction is slight.The strength decreases gradually,and the ductility gradually increased gradually.The particle size,interface reaction and matrix material affect the mechanical properties of B4C reinforced aluminum matrix composites.