(1. 哈尔滨工业大学 材料科学与工程学院，哈尔滨 150001；2. 哈尔滨工业大学 微纳米技术研究中心，哈尔滨 150001)
摘 要: 利用新的金属型微精密铸造工艺制备微米尺度的ZnAl4微齿轮铸件，并用纳米压痕仪测试微铸件的硬度和弹性模量。结果表明，微齿轮铸件不同部位的硬度表现出梯度性，随晶粒尺寸的增加而减小，弹性模量的值比较分散。与常规尺寸铸件的显微硬度相比，微铸件硬度明显提高，最大达到1.70倍，而弹性模量则下降约50%。分析表明快冷造成的非平衡凝固组织是性能改变的主要原因。
关键字: ZnAl4；合金微精密铸造；纳米压痕；纳米硬度；弹性模量
（1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;2. Micro/nano Technology Research Center, Harbin Institute of Technology, Harbin 150001, China）
Abstract:Micrometer scale gear was manufactured by new micro-precision casting technology based on metal mold, and its hardness and elastic modulus were measured by nanoindentation. The results show that the hardness of microcastings is dependent on the grain size, and decreases with the increase of the grain size. Value of elastic modulus scattered. The hardness of microcastings is higher than that of conventional castings, the maximum up to 1.70 times, but the elastic modulus decreases by about 50%。The property change is caused by the microstructure of non-equilibrium solidification from rapid cooling.
Key words: ZnAl4 alloy; micro-precision casting; nanoindentation; nanohardness; elastic modulus
