Zhang Jizhai1, Ma Ying1, Chen Tijun1, et al. Effects of Semi-solid Isothermal Treatment on Microstructure of AM60B Magnesium Alloy. [J]. Special Casting & Nonferrous Alloys 29(4):337-340(2009)
Zhang Jizhai1, Ma Ying1, Chen Tijun1, et al. Effects of Semi-solid Isothermal Treatment on Microstructure of AM60B Magnesium Alloy. [J]. Special Casting & Nonferrous Alloys 29(4):337-340(2009)DOI:
Effects of Semi-solid Isothermal Treatment on Microstructure of AM60B Magnesium Alloy
摘要
研究了半固态等温处理工艺对金属型AM60B的组织和初生相尺寸及形态的影响。结果表明
在半固态等温热处理过程中
网状分布的共晶组织先发生熔化;随着等温时间的延长
α相发生熔化分离;等温时间过长时
球状颗粒有长大、合并的趋势
等温温度越高
晶粒间的合并现象越严重。结果表明
在595℃时保温60~75min可以获得较好的球状非枝晶组织;经过两步法短时的高温保温
非枝晶转变进程加快
可以得到较细小均匀的非枝晶组织。
Abstract
Effects of holding time and temperature on the microstructure and size as well as morphology of primary phase in AM60B alloy during semi-solid isothermal treatment process were investigated. The results show that during semi-solid isothermal treatment
eutectic phase with net-like structure is prior to be melt
and then α phase is melt and separated to that to convert into globular particles with increasing in holding time. However
spheroidal particle can be coalesced with further increasing in holding time
where coalescence of the grain becomes more and more serious with increasing in holding temperature. The experimental results reveal that spheroidized non-dendrite phase in the AM60B alloy can be observed with isothermal treatment at 595℃ for 60
7
5 min. Two-steps techniques can promote the formation of non-dendritic structure and contribute to get more and fine non-dendrite .