Al-Cu-Sc铝合金板材不同热处理状态下的组织和力学性能研究  

Research on microstructure and mechanical properties of Al-Cu-Sc aluminum alloy sheet under different heat treatment conditions

作　　者：崔晓磊[1] 刘章光 赵远杨 马向宇 华坤 CUI Xiao-lei;LIU Zhang-guang;ZHAO Yuan-yang;MA Xiang-yu;HUA Kun(National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin 150001,China;Beijing Xinghang Mechanical-Electric Equipment Co.,Ltd.,Beijing 100074,China)

机构地区：[1]哈尔滨工业大学金属精密热加工国家级重点实验室,黑龙江哈尔滨150001 [2]北京星航机电装备有限公司,北京100074

出　　处：《塑性工程学报》2024年第9期135-143,共9页Journal of Plasticity Engineering

基　　金：中国博士后科学基金资助项目(2023T160158,2020M670907)。

摘　　要：以厚度为3 mm的Al-Cu-Sc铝合金板材为研究对象,利用EBSD技术对人工时效态(T6态)和退火态(O态)板材的微观组织进行分析;对T6态、O态、W态以及经过预拉伸变形和人工时效处理得到的T8态板材在室温下进行单向拉伸测试,研究不同热处理状态下板材的力学性能变化规律。结果表明:T6态和O态板材中都存在[001]方向的织构,且O态板材的织构更强。T6态板材的晶界以大角度晶界为主,O态板材的晶界以小角度晶界为主,且其晶粒尺寸远大于T6态板材。T6态和W态Al-Cu-Sc板材轧制方向与横向强度基本一样,而O态板材轧向强度明显高于横向。O态板材的强度最低,T6态板材的塑性最差,而W态板材具有最小的屈强比和最大的应变硬化指数n值,成形性能最好。此外,经过预拉伸和人工时效后得到的T8态板材强度显著提升,当预拉伸变形量为5%和7%时,T8态板材抗拉强度超过500 MPa。The microstructure of Al-Cu-Sc aluminum alloy sheet with thickness of 3 mm was analyzed with EBSD technique under the artificial aging state(T6 state)and annealing state(O state).Moreover,uniaxial tensile tests were carried out at room temperature on the T6 state,O state and W state sheets,as well as T8 state sheet obtained by pre-tension deformation and artificial aging treatment,and the change laws of mechanical properties of the sheets under different heat treatment conditions were studied.The results show that the texture in the direction of[001]exists in both T6 state and O state sheets,and the texture in the O state sheet is stronger.The grain boundaries of the T6 state sheet are dominated by high angle grain boundaries,while the grain boundaries of the sheets in the O state are dominated by low angle grain boundaries,and the grain size is much larger than that of the T6 state sheet.The strength in rolling direction and transverse direction of the Al-Cu-Sc sheets in T6 state and W state is basically the same,while the strength in rolling direction of the O state sheet is obviously higher than that in the transverse direction.The O state sheet has the lowest strength,the T6 state sheet has the worst plasticity,and the W state sheet has the best formability with the smallest strength ratio and the largest strain hardening exponent n value.In addition,the strength of the T8 state sheet obtained after pre-tension and artificial aging is significantly increased.When the pre-tension deformation is 5%and 7%,the tensile strength of the T8 state sheet is higher than 500 MPa.

关 键 词：Al-Cu-Sc合金板材 热处理 微观组织 轧制方向 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]