Al2O3/Cu复合材料的高温拉伸性能研究

Al2O3弥散强化铜复合材料(ADSCC)因其具有优良的高强度高导电性能以及抗高温软化性能而成为备受瞩目的一种工程材料.研究了ADSCC的微观组织和拉伸性能.研究表明该材料相比Cu-Cr合金(Cr0.7%)在高温下具有很高的强度保持比.材料的强度随温度的升高而下降.对ADSCC的微观组织研究表明该材料的强度高主要是因为Al2O3颗粒的弥散分布限制了位错运动,阻碍了晶粒长大和Cu基体的再结晶.动态回复和局部再结晶是主要的软化机制.断裂特征表现为局部韧性断裂.

High Temperature Tensile Behavior of Al2O3/Cu Composite

Alumina dispersion strengthened copper composite(ADSCC) is an attractive engineering material for applications requiring high strength,high thermal and electrical conductivities and resistance to softening at elevated temperatures.The microstructure and tensile behavior of an ADSCC is examined.The results show that the material maintains a high value of strength retention ratio compared to Cu-Cr(Cr 0.7%) alloy at elevated temperatures.The strength of the material decreases with the increase of test temperature.The study on microstructure reveals that the strengthening of ADSCC is mainly attributed to the presence of the alumina particles which can hamper the mobility of dislocations,hinder grain growth and restrict the copper matrix recrystallization.Dynamic recovery and local recrystallization is the main softening mechanism.The fracture features are reminiscent of locally ductile failure.