摘要
挤压铸造了Mg-9Gd-1Y-0.5Zr(GW91)活塞,研究了固溶时效态(T6)活塞顶部及裙部的力学性能,以及在200～300℃的蠕变性能。结果表明,活塞经过固溶时效处理后,晶粒内部析出相均匀析出,顶部和裙部平均晶粒尺寸分别为140、80μm;T6态活塞的抗拉强度随温度增加而降低,当温度为300℃时,活塞顶部及裙部抗拉强度分别达到210、223MPa;T6态活塞稳态蠕变速率随温度及应力增加而增大,在300℃、50MPa蠕变条件下,活塞顶部及裙部稳态蠕变速率分别为7.81×10-8s-1、1.45×10-7s-1,蠕变100h后蠕变量分别为2.8%、3.0%,优于现阶段商用活塞材料Al-Si合金的高温抗拉强度和抗蠕变性能。
The Mg-9Gd-1Y-0.5Zr（GW91） alloy piston was produced by squeezing casting.The mechanical properties of the samples cut from piston top and skirt at the peak-aged condition（T6） and its creep resistance at 200~300 ℃ were investigated.The results reveal that precipitates in grain is uniformly distributed in the T6 treated piston,and the grain size in piston top and skirt treated by T6 reaches 140 μm and 80μm,respectively.Meanwhile,the tensile strength of piston is decreased with increasing in temperature,and the ultimate tensile strength（UTS） of piston top and skirt are 210 MPa and 223 MPa,respectively,at 300 ℃.The steady-stage creep rate of piston is increased with increasing in temperature and applied stress.The steady-stage creep rate of piston top and skirt are 7.81×10-8 s-1 and 1.45×10-7 s-1,and total creep strain after 100 h are 2.8% and 3.0%,respectively,at 300 ℃ and 50 MPa,evidently superior to those of commercial Al-Si alloy.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2012年第10期907-911,共5页
Special Casting & Nonferrous Alloys
基金
国家十二五科技支撑计划项目(2011BAE22B01-5)
国家自然科学基金资助项目(51074106)
