摘要
采用自孕育法制备ZA92镁合金半固态浆料,研究了等温热处理工艺对ZA92镁合金半固态组织演变的影响.结果表明：保温温度为595℃,保温时间为4～6 min时,晶粒较好,其晶粒尺寸在70μm左右,圆整度为1.3左右;不同的保温温度（585、590、595、605℃）对浆料形成不同的过冷度（ΔT）,过冷度决定了晶粒的形核与长大,合适的保温温度有利于初生α-Mg的细化和稳定生长;自孕育流变在线制备浆料的过程中,晶粒的生长是原子堆积的过程,随着保温时间的延长,其组织演变满足Ostwald熟化理论.
Semi-solid slurry of ZA92 magnesium alloy was prepared by self-inoculation method （SIM）. The effect of isothermal heat treatment process on semi-solid microstructure evolution was investigated. The results show that the grain is fine when the isothermal temperature is 595 ℃ and the isothermal time is 4-6 min. The grain size is 70 μm, and the spherical degree is 1.3. The different undercooling （AT） is effected by the different isothermal temperature （585 ℃, 590 ℃, 595 ℃, 605 ℃ ）, which determines nucleation and growth of the grain. Suitable isothermal temperature is benefit to the refinement of primary α-Mg phase and stable growth. In online prepared semi-solid slurry by SIM, grains continue to grow because of atoms cumulation. With the isothermal time prolonging, the microstructure evolution meet ostwald ripening.
出处
《铸造》
CAS
CSCD
北大核心
2014年第5期495-499,共5页
Foundry
基金
国家自然科学基金(21273171)
陕西省科技统筹创新工程计划(2012KTDZ02-02-01)
商洛学院科研项目(13SKY008
13SKY006)
关键词
等温热处理
ZA92
自孕育法
半固态组织
isothermal heat-treatment
ZA92
self-inoculation method
semi-solid microstructure
