喷射成型Zn60Al32Cu2Si6微观形貌及耐磨性能的研究

Study on Microstructure and Wear Resistance of Zn60Al32Cu2Si6 Alloy Prepared by Spray Deposition

采用喷射成型工艺制备了成分为Zn60Al32Cu2Si6的高铝锌铝合金,并利用X射线衍射仪、扫描电镜等对合金的物相组成、微观形貌及磨损形貌进行了表征,利用摩擦磨损试验机对合金的耐磨性能进行了研究。结果表明:沉积态合金主要由过饱和的富铝相α′、富锌相η、硅相和沉淀强化相-εCuZn4组成,没有出现粗大的树枝晶,无严重偏析现象,且含有大量的共析层片状组织。挤压时效初期合金有典型的时效硬化特性,但是后期由于发生四相反应α+ε→Τ′+η,硬度反而下降,后期合金的组织为富铝相α、富锌相η、硅相和少量的T′。与铸造态相比,喷射成型制备的合金的耐磨性能有所增加,摩擦系数与磨损量都显著降低。

The phase composition,microstructure and wear morphology of the specimens of the captioned alloy were investigated by XRD diffraction and SEM.Its wear resistance was studied by friction and wear testers.It was found that the deposited alloy consists of aluminum rich phase,zinc rich phase,silicon phase and deposition strengthened phase CuZn4.No coarse dendrite and no serious segregation were found.There was plenty of eutectoid lamellar structure.Age hardening characteristics were found in the initial ageing stage.But the hardness decreased in the later stage because of the four phase reaction.In the later ageing stage,the specimen consists of aluminum rich phase,zinc rich phase,silicon phase and T＇ phase.The wear resistance of the alloy prepared by spray deposition decreased.Friction and wear losses decreased significantly.