Mn元素对2024铝合金铸态组织及力学性能的影响研究  

Study on the effect of Mn element on as-cast microstructure and mechanical property of 2024 aluminium alloy

作　　者：王东辉 孙祥彬 祝哮 李洪林 刘迪 WANG Donghui;SUN Xiangbin;ZHU Xiao;LI Honglin;LIU Di(Liaoning Zhongwang Group Co.,Ltd.,Liaoyang 111003,China)

机构地区：[1]辽宁忠旺集团有限公司,辽宁辽阳111003

出　　处：《铝加工》2025年第2期14-20,共7页Aluminium Fabrication

摘　　要：通过JmatPro热模拟软件分析绘制了不同Mn元素质量分数的2024铝合金凝固热力学曲线,推测不同Mn元素质量分数的2024铝合金凝固状态所含合金相及其析出温度,并结合微观组织分析和力学性能试验,研究了Mn元素质量分数对2024铝合金组织及性能的影响,以及退火制度对2024铝合金微区偏析的影响。结果表明:Mn元素具有细化晶粒的作用,随着Mn元素质量分数的增大,铸态2024铝合金的晶粒尺寸逐渐减小,当Mn元素质量分数达到0.7%时,晶粒组织呈等轴状;基体内的Mn元素大多在晶界处聚集,且随着Mn元素质量分数的不断升高,这些富Mn相会逐渐长大,形成粗大相,进而影响合金的力学性能;随着Mn元素质量分数的逐渐升高,2024铝合金的力学性能先升高后降低,在Mn元素质量分数为0.5%时力学性能最好,屈服强度、抗拉强度和断后伸长率分别为199 MPa、245 MPa和4.0%;2024铝合金铸锭的最佳均匀化制度为495℃×16 h。By using JmatPro thermal simulation software,the solidification thermodynamic curves of 2024 aluminium alloy with different Mn mass fractions were analyzed and drawn,speculating on the alloy phase and precipitation temperature of 2024 aluminium alloy with different Mn mass fractions in the solidification state.Combined with microstructure analysis and mechanical property experiment,the effect of Mn mass fraction on microstructure and mechanical property of 2024 aluminium alloy,as well as the effect of annealing process on microsegregation of 2024 aluminium alloy.The results show that Mn has the effect of refining grain.With the increase of Mn mass fraction,the grain size of as-cast 2024 aluminium alloy decreases gradually.When the Mn mass fraction reaches 0.7%,the grain structure is equiaxed.Most of the Mn elements in the matrix aggregate at the grain boundaries,and with the increase of Mn mass fraction,these Mn-rich phases gradually grow and form coarse phases,which futher affect the mechanical property of the alloy.With the gradual increase of Mn mass fraction,the mechanical property of 2024 aluminium alloy first increases and then decreases.When the Mn mass fraction is 0.5%,the mechanical property is the best,and the yield strength,tensile strength and elongation are 199 MPa,245 MPa and 4.0%,respectively.The optimal homogenizing annealing process of 2024 aluminium alloy ingots is 495℃×16 h.

关 键 词：2024铝合金 MN元素 显微组织 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程]