Al-Si-Cu-Mg(-Er)铸造铝合金的低周疲劳行为  

Low-Cycle Fatigue Behavior of Cast Al-Si-Cu-Mg(-Er) Aluminum Alloy

作　　者：车欣[1] 徐志军[2] 陈立佳[1] 徐海健[1] 李锋[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,辽宁沈阳110870 [2]空军装备研究院导技所,北京100085

出　　处：《铸造》2011年第1期20-23,共4页Foundry

基　　金：辽宁省高校重点实验室支持计划资助项目(2008S163)

摘　　要：对金属型铸造Al-Si-Cu-Mg和Al-Si-Cu-Mg-Er铝合金进行了疲劳试验,并研究了其室温下的低周疲劳行为。试验结果表明:金属型铸造Al-Si-Cu-Mg和Al-Si-Cu-Mg-Er铝合金表现为循环应变硬化和循环稳定,主要取决于外加总应变的高低;稀土元素Er的加入可提高金属型铸造Al-Si-Cu-Mg合金的循环变形抗力和疲劳寿命;金属型铸造Al-Si-Cu-Mg合金的塑性应变、弹性应变与断裂时的载荷反向次数之间呈直线关系,Al-Si-Cu-Mg-Er合金的弹性应变与疲劳断裂时的载荷反向次数之间也呈直线关系,但其塑性应变与疲劳断裂时的载荷反向次数之间则呈双线性关系。Through the strain-controlled fatigue experiments, the low-cycle fatigue behavior of permanent-mold cast Al-Si-Cu-Mg and Al-Si-Cu-Mg-Er alloys at room temperature was investigated. The experimental results show that the Al-Si-Cu-Mg and Al-Si-Cu-Mg-Er alloys exhibit the cyclic strain hardening and cyclic stability, mainly depending on the imposed total strain amplitude. For the permanent-mold cast Al-Si-Cu-Mg alloy, the addition of Er can effectively enhance both cyclic deformation resistance and fatigue life of the alloys. A single-slope linear relation between plastic strain amplitude, elastic strain amplitude and reversals to failure is observed for permanent-mold cast Al-Si-Cu-Mg alloy. However, a two-slope linear relation between plastic strain amplitude and reversals to failure is noted for the Al-Si-Cu-Mg-Er alloy, although the corresponding relation between elastic strain amplitude and reversals to failure is linear.

关 键 词：铝合金 金属型铸造 ER 低周疲劳 疲劳寿命 循环应力响应 

分 类 号：TG292[金属学及工艺—铸造]