摘要
采用静载荷实验和扫描电镜,研究了pH值对触变成形和金属型AZ91D镁合金应力腐蚀行为的影响。通过对试验现象、试样断裂时间及断口形貌的对比分析,结果表明:触变成形AZ91D镁合金的抗应力腐蚀敏感性明显高于金属型AZ91D镁合金的。主要是由于触变成形工艺的优良性,使得镁合金的组织在二次加热等温处理的过程中具有了球状的组织结构,而并非像金属型那样的树枝晶状的组织。同时这种成形工艺也降低了铸件的缩松、气孔和氧化夹杂等缺陷。
Influence of pH on stress corrosion behavior of thixoformed and metal mould AZ91D magnesium alloy was investigated by means of constant load test and SEM. By analysis of experiment phenomenon, fracture time and fracture morphology. The results indicated that low SCC susceptibility of test sample of thixoformed is obviously higher than that of metal mould. Mainly because thixoformed craft was excellent. Make the organization of the magnesium alloy has spherical particle in the course of reheating and isothermal treatment, it is not the initial dendrite organization. Meanwhile, this kind of craft reduced defect of cavity and oxide inclusion of test sample.
出处
《铸造》
EI
CAS
CSCD
北大核心
2006年第8期835-838,共4页
Foundry
基金
"863"计划国际合作项目(2002AADF3303)
第三批中-以合作基金项目(2002-02)。
关键词
AZ91D镁合金
触变成形
应力腐蚀
断口形貌
杂质
AZ91D magnesium alloy
thixoformed
stress corrosion
fracture morphology
impurity
