多级时效对低压铸造A356.2轮毂力学性能的影响

研究了多次人工时效对低压铸造A356.2铝合金轮毂力学性能的影响.结果表明,T6处理后,再经过3次人工时效,合金的抗拉强度、屈服强度、硬度有所提高,但伸长率有所下降;随人工时效次数的继续增多,力学性能变化幅度渐小,组织结构趋于稳定;轮辐部位的晶粒较轮缘部位的晶粒粗,二者屈服强度和硬度的差别不大,但轮辐部位的抗拉强度和伸长率比轮缘部位低.

Effects of Multi-artificial Aging on Mechanical Proper-ties of Low Pressure Casting A356. 2 Aluminum Alloy Wheel

Effects of multi-artificial aging on mechani-cal properties of low pressure casting A356.2 alumi-num alloy wheel were investigated. The results show that tensile strength, yield strength and hardness are slightly improved, however, the elongation is de-creased in multi-artificial aging alloy. The fluctuating amplification of mechanical properties is weakened with increasing in artificial aging times, so the micro-structure tends to stable. After T6 heat treatment, al- though coarse grain size in A356.2 alloy can affect the absence of yield strength and hardness, it can decrease tensile strength and elongation of the alloy wheel. The results show that with multi-artificial aging, the strength and hardness of the A356.2 aluminum alloy wheel are increased with the decrease of elongation and the stability of properties. However, the elonga-tion of the alloy is deteriorated with increase in grain size in A356.2 aluminum alloy in low pressure cast-ing.