采用真空熔炼-离心铸造工艺制备新型ZCuSn10Zn2Fe1.5合金.通过扫描电镜研究了热处理前后合金的组织变化和元素分布,得到了热处理使Sn偏析减轻的证据.采用原位拉伸试验对热处理前后试样的断裂过程进行了研究和分析,结果表明:铸态ZCuSn 10Zn2Fe 1.5合金裂纹优先萌生于脆硬的8相,微裂纹易沿着δ相与基体晶粒界面扩展；热处理后ZCuSn10Zn2Fe1.5合金内部的δ相基本消失,微裂纹在基体晶粒内部萌生和扩展；合金试样经过750℃固溶2h和500℃时效4h后,抗拉强度和伸长率分别达到420 MPa和45％,比热处理前分别提高10.5％和20％.%New type of ZCuSn10Zn2Fe1.5 alloy was fabricated by centrifugal casting in vacuum chamber,the elements distribution and the microstructure change of alloy was studied through the scanning electron microscopy,and the results demonstrate that the heat treatment process can decrease the Sn segregation.Fracture mechanism has been investigated and analyzed by in-situ tensile experiments on as cast ZCuSn10Zn2Fe1.5 and alloy after heat treatment under different stress states.The results indicate that crack initiates first in the δ phase and propagates along the interface of δ phase and matrix grain.The δ phase largely disappear in the alloy after heat treatment,the crack initiates and propagates in matrix grains.After solution treatment for 2 h at 750 ℃,quenching and aging for 4 h at 500 ℃,alloy exhibit tensile strength of 420 MPa and uniform elongation of 45％,compared with former alloy the tensile strengths and the elongation has been increased by 10.5％ and 20％ respectively.
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