摘要
测试了循环次数为104和150℃条件下A356铝合金缸盖的疲劳性能。试验数据采用S-N曲线和升降法进行处理,两种处理方法所得的疲劳强度数值相当。经过光学显微镜和扫描电镜观察疲劳样品断口发现:在一个疲劳样品的断口中出现多个裂纹源;缸盖铸件的主要铸造缺陷是氧化夹杂和缩松。相比氧化夹杂,缩松对铝合金铸件疲劳性能的恶化更加严重。
The fatigue property of A356 cast alloy was investigated under 104 cycles at 150 ℃. The testing data were treated by S-N curve and staircase method and the mean values of fatigue property coincided with each other using these two methods. The fracture surfaces of fatigue specimens were examined with OM and SEM. It was found that in the most of specimens two or more fatigue crack initiations appeared in a fracture surface. Oxide film and shrinkage porosity were major casting defects in the cylinder head castings. Compared with casting defects such as oxide film, shrinkage porosity was more detrimental to the fatigue behavior.
出处
《上海金属》
CAS
北大核心
2015年第5期6-10,共5页
Shanghai Metals
关键词
铸造缺陷
A356铝合金
缸盖
疲劳性能
Casting Defect, A365 Aluminum Alloy, Cylinder Head, Fatigue Behavior
