固溶处理对TiB2/6061复合材料硬度及耐磨性的影响

Influence of solution treatment on hardness and wear resistance of TiB2/6061 composites

采用氟盐法制备了TiB2质量分数为3%的原位合成TiB2/6061复合材料,研究了固溶温度和固溶时间对复合材料硬度和耐磨性能的影响。结果表明:TiB2颗粒弥散分布在6061铝合金基体中,明显细化6061铝合金基体晶粒。当固溶温度一定时,随固溶时间延长,复合材料的硬度和耐磨性可获得明显提高,但固溶时间在6~10 h时,复合材料的性能变化不显著。当固溶时间一定时,随固溶温度升高,复合材料硬度和耐磨性呈现先上升后下降的趋势。3wt%TiB2/6061复合材料经530℃×10 h固溶处理后,硬度和耐磨性能最佳,相较于铸态硬度值提高了79.5%,磨损量减少了59.1%。固溶处理后复合材料的磨损表面犁沟变细变浅,材料脱落现象减少。

TiB2/6061 composites with 3%TiB2 was prepared by means of fluoride salt method.The effects of solution temperature and solution time on hardness and wear resistance of the composites were studied.The experimental results show that TiB2 particles are dispersed in the 6061 Al alloy matrix,and the 6061 Al alloy matrix grains are significantly refined.As the solution temperature is constant,the hardness and wear resistance of the composites increase obviously with the increase of the solution time.However,as the solution time is 6-10 h,the properties of the composites do not change significantly.As the solution time is constant,the hardness and wear resistance of composites increase first and then decrease with the increase of solution temperature.Compared with as cast 3 wt%TiB2/6061 composite,the in-situ synthesized 3 wt%TiB2/6061 composite has the best hardness and wear resistance after solution treatment at 530℃ for 10 h,and the hardness of the composite is increased by 79.5%and the wear loss is decreased by 59.1%.After solution treatment,the plough grooves on the worn surface of the composites become finer and shallower,and the material shedding phenomenon decreases.