La、Cr及热处理对汽车用铝合金组织和性能的影响

Effect of La/Cr and Heat Treatment on Microstructure and Properties of Al Alloy for Automobile

研究了La、Cr元素和时效处理对G1铝合金组织和性能的影响。结果表明,随着La含量的增加,铝合金抗拉强度和冲击韧性先增加后减小,La含量0.12%时达到最大值,分别为218.3 MPa和19.6 J/cm2。Cr含量添加到0.2%时,铝合金抗拉强度达到极大值210.5 MPa,冲击韧性达到28.3 J/cm2。添加La元素和Cr元素后,铝合金最佳时效处理制度为160℃×12 h,抗拉强度达到293.5 MPa。

The effects of La, Cr and aging treatment on the microstructure and properties of GI A1 alloy were studied. The results show that with the increase of La content, the tensile strength and impact toughness of the aluminum alloy firstly increase and then decrease. When the content of La is 0.2%, the tensile strength and impact toughness reach maximum values （218.3 MPa and 19.6 J/cm2）. When the content of Cr is 0.2%, the tensile strength of AI alloy reaches 210.5 MPa, and the impact toughness reaches 28.3 J/cm2. Adding La and Cr elements, the best aging treatment system of the aluminum alloy is 160℃ for 12h, and tensile strength reaches 293.SMPa.