Cu-Zn-Al-Ni合金的组织与性能

Microstructures and properties of Cu-Zn-Al-Ni alloy

采用熔铸和轧制的方法,在Cu-Zn-Al铝黄铜中添加Ni及自制晶粒细化剂,制备出一种新型弹性合金,通过扫描电子显微镜(SEM)和光学显微镜(OM)等对Cu-Zn-Al-Ni铝黄铜的微观组织进行观察、分析,并对其抗拉强度、延伸率、弹性模量等相关参数进行研究。研究结果表明:在合金铸态组织中,Ni,Al和Ti以三元金属间化合物形式主要分布在晶界上,在轧制过程中阻碍基体变形和晶界移动,从而提高合金强度;在均匀化退火过程中,合金中出现层片状Al3Ni相,弥散分布在基体内,在冷轧加工后转变为颗粒状;合金再结晶开始温度为350℃,低于再结晶温度退火时,冷轧态合金存在低温退火硬化效应,于250℃退火,硬度达到峰值;冷轧态板材最终退火后,其抗拉强度为731 MPa,延伸率为15%,弹性模量为120 GPa。

A new elastic alloy Cu-Zn-Al aluminum brass containing Ni and grain refiner was produced by casting and rolling.The microstructures of studied alloy were investigated by means of OM and SEM;the tensile strength,hardness and elastic modulus were studied.The results show that Ni and Ti can combine with Al to generate intermetallic compound which mainly distributes on the grain boundaries in as-cast structure.They can improve the mechanical properties of the studied alloy by preventing the deformation of matrix and movement of the grain boundaries.Furthermore,Ni and Al generate a new dispersed second phase Al3Ni after homogenizing treatment which are dispersively distributed into the matrix and turn from lamellar-type to granule during the cold rolling.The recrystallization temperature of the alloy is 350 ℃,hardening effect happens in the process of low temperature annealing and the peak hardness of the alloy can be attained at 250 ℃.The tensile strength,elongation and module of the aluminum alloy after final annealing are 731 MPa,15% and 120 GPa,respectively.