激光熔覆修复5083铝合金组织和力学性能研究

Structure of 5083 aluminum alloy restored with laser cladding and its mechanical property study

采用传统商用AlSi10Mg合金粉末与中车工业研究院自主研发的高强高塑AlMgScZr合金粉末,以轨道交通常用的5083铝合金车体为修复对象,并预制梯形凹槽以模拟破损状况,通过激光熔覆修复,对其微观组织和力学性能进行了对比分析。结果表明:AlSi10Mg合金粉末修复样件修复区晶粒主要为柱状晶,修复后拉伸强度为188 MPa,屈服强度为96 MPa,延伸率为4.63%。AlMgScZr合金粉末修复样件修复区晶粒以等轴晶为主,修复后拉伸强度为310 MPa,屈服强度为222 MPa,延伸率为12.5%,可达到甚至超过5083铝合金母材强度。

Taking 5083-H112 aluminum alloy commonly used in rail transit sector as the target for renovation and simulating damaged condition with prefabricated trapezoidal grooves, laser cladding repair is implemented by using traditional AlSi10 Mg powdered alloy and the high strength high ductility AlMgScZr powdered alloy independently developed by CRRC Industrial Research Institute, followed by contrastive analysis of its microstructures and mechanical properties. Test results indicate that the crystal grain at the repair zone of the sample renovated with AlSi10 Mg powdered alloy is mainly columnar crystal, with a tensile strength of 188 MPa, a yield strength of 96 MPa and an elongation of 4.63% after the renovation. The crystal grain at the repair zone of the sample renovated with AlMgScZr powdered alloy is mainly isometric crystal, with a tensile strength of 310 MPa, a yield strength of 222 MPa and an elongation of 12.5%, coming up to or even exceeding the strength of 5083 aluminum alloy substrate.