摘要
在300℃温度下对ZK60镁合金进行了不同道次的等通道挤压(ECAP)。研究了ECAP挤压对合金显微组织、室温力学性能和高温抗蠕变性能的影响。结果表明,合金铸态组织主要由α-Mg基体、Mg7Zn3相和MgZn相组成。等通道挤压可显著破碎层片状MgZn相并使其趋于弥散分布,同时基体组织也得到细化。挤压2道次后,合金的室温抗拉强度由170MPa增加到250MPa,伸长率由7%增加到17.7%。挤压4道次后,合金的伸长率进一步增加到20%,而抗拉强度却下降至242MPa;合金的高温蠕变寿命由铸态1.4h延长到44.8h,稳态蠕变速率减小了约一个数量级。
ZK60 magnesium alloy was extruded by equal channel angular pressing （ECAP） at 300℃, which was undergone transmutation of different passes. The effects of ECAP on microstructure, mechanical properties at room temperature and high-temperature creep resistance of the alloy were investigated. Experimental results show that the microstructure of as-cast alloy are mainly a-Mg matrix, Mg7Zn3 and MgZn phases. During ECAP processing, the original layer flake MgZn phases are significantly broken into particles which tend to dispersive distributing and the matrix is also refined. After 2 passes of EACP, the tensile strength and elongation of the alloy at room temperature increases from 170MPa and 7% to 250MPa and 17.7%, respectively. After 4 passes of EACP, elongation further increases to 20%, but tensile strength drops to 242MPa; the high-temperature creep life of alloy is extended from 1.4h （as-cast） to 44.8h, and the steady creep rate decreases an order of magnitude.
出处
《热加工工艺》
CSCD
北大核心
2013年第1期4-7,共4页
Hot Working Technology
基金
山西省青年科技研究基金项目(2008021033)
山西省自然科学基金项目(2010011033-1)
山西高校科技研究开发项目(2007110)
