过共晶铝硅合金的组织和热膨胀行为  

Microstructure and thermal expansion behavior of hypereutectic Al-Si alloy

作　　者：朱学卫[1,2] 王日初[1] 彭超群[1] 彭健[1] 

机构地区：[1]中南大学材料科学与工程学院,湖南长沙410083 [2]西北农林科技大学机械与电子工程学院,陕西杨凌712100

出　　处：《中南大学学报（自然科学版）》2016年第5期1500-1505,共6页Journal of Central South University:Science and Technology

基　　金：国家军品配套项目(JPPT-125-GH-039)~~

摘　　要：采用喷射沉积技术制备过共晶Al Si27合金,研究热处理对其显微组织的影响,并探讨Al Si27合金在室温至500℃范围内的热膨胀行为。研究结果表明:喷射沉积Al Si27合金中,细小的初晶Si颗粒在Al基体中均匀分布,且初晶硅尺寸随退火温度升高而增大,由细小球状颗粒逐渐转变成为粗大球状或长条状颗粒。随退火温度升高,材料的残余热应力逐渐减小,室温至100℃范围内的热膨胀系数逐渐增大。此外,不同循环温度下的热膨胀系数随循环温度的升高而逐渐增大,且实测值与Kerner模型理论计算值一致。The hypereutectic Al Si27 alloy was prepared by spray-formed process. The microstructure and thermal expansion behavior between room temperature and 500 ℃ of hypereutectic Al Si27 alloy were investigated. The results show that the primary Si phases are uniform distribution in the spray-formed Al Si27 alloy, and the primary Si phase grows form fine spherical particle to bulky spherical particle or strip-like phase with the increase of aging temperature. The coefficient of thermal expansion（CTE） between room temperature and 100 ℃ of the Al Si27 alloy increases gradually with the increase of aging temperature. On the other hand, the CTE at different cycling temperature is almost linearly increased with the increase of temperature, and agreed well with the Kerner model.

关 键 词：喷射沉积 过共晶铝硅合金 残余热应力 热膨胀系数 

分 类 号：TG146.21[一般工业技术—材料科学与工程]