T6态热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金的低周疲劳行为  

Low-cycle fatigue behavior of hot-extruded Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag alloy at T6 state

作　　者：王莹[1] 陈立佳[1] 周舸 张浩宇 张思倩[1] WANG Ying;CHEN Lijia;ZHOU Ge;ZHANG Haoyu;ZHANG Siqian(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,Liaoning,China)

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

出　　处：《沈阳工业大学学报》2024年第1期77-81,共5页Journal of Shenyang University of Technology

基　　金：国家自然科学基金区域创新发展联合基金重点项目(U21A20117)。

摘　　要：为了揭示经过T6处理的热挤压Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag合金在不同温度下的低周疲劳变形与断裂行为,对T6态热挤压合金进行了室温和200℃条件下的低周疲劳实验。结果表明:在室温和200℃下合金塑性应变幅与载荷反向周次之间服从Coffin-Manson公式,而弹性应变幅与载荷反向周次之间服从Basquin公式;合金在室温和200℃下低周疲劳变形时,在较低外加总应变幅下疲劳变形机制主要为平面滑移,而在较高外加总应变幅下疲劳变形机制主要为波状滑移;室温和200℃下合金的疲劳裂纹均萌生于疲劳试样表面并以穿晶方式扩展。In order to reveal the low-cycle fatigue deformation and fracture behavior of hot-extruded Al-5Cu-0.8Mg-0.15Zr-0.2Sc-0.5Ag alloy subjected to T6 treatment,the low-cycle fatigue tests were performed at both room temperature and 200℃ with this alloy at T6 state.The experimental results show that the relationship between plastic strain amplitude and load reversal cycle follows the Coffin-Manson formula at both room temperature and 200℃,while the relationship between elastic strain amplitude and load reversal cycle follows the Basquin formula.During the low-cycle fatigue deformation at both room temperature and 200℃ of the alloy,the deformation mechanism is mainly the planar slip at lower total strain amplitudes,while is mainly the wavy slip at higher total strain amplitudes.At both room temperature and 200℃,the low-cycle fatigue cracks initiate at the free surface of fatigue specimens and propagate in a transgranular mode.

关 键 词：AL-CU-MG-AG合金 T6处理 低周疲劳 循环硬化 循环稳定 疲劳寿命 变形机制 疲劳断裂 

分 类 号：TB31[一般工业技术—材料科学与工程]