化学铣切对2524-T3铝合金薄板表面形貌和性能的影响

Effect of Chemical Milling on Surface Morphology and Properties of 2524-T3 Aluminum Alloy Sheet

对2524-T3铝合金薄板进行化学铣切试验,研究了化学铣切前后薄板的表面形貌、拉伸性能和疲劳性能。结果表明:化学铣切前薄板表面存在尺寸为5~10μm的粗大第二相粒子AlCuMg和氧化物,化学铣切后表面出现大量直径为10~50μm的浅表腐蚀坑,还有第二相粒子部分溶解剥离而残留的微孔洞,表面粗糙度提高;化学铣切对薄板的室温拉伸性能无显著影响,化铣前后的屈服强度不低于330 MPa,抗拉强度不低于460 MPa,断后伸长率保持在20%以上;化铣前后薄板的疲劳强度分别为153.5,138.3 MPa,化铣后疲劳强度相比化铣前下降了9.9%。

Chemical milling test of 2524-T3 aluminum alloy sheet was carried out.The surface morphology,tensile properties and fatigue properties of the sheet before and after chemical milling were studied.The results show that before chemical milling,the coarse second phase particles AlCuMg and oxides with size of 5-10μm existed on surface of the sheet.After chemical milling,a large number of shallow corrosion pits with diameter of 10-50μm,and micro-holes formed by stripped of the matrix after the second phase particles dissolving and stripping appeared on the surface resulting in the increase of surface roughness.Chemical milling had no significant effect on the room temperature tensile properties of sheet.The yield strength and tensile strength before and after chemical milling were not less than 330 MPa and 460 MPa,respectively,and the elongation percentage after fracture were kept above 20%.The fatigue strength of the sheet before and after chemical milling were 153.5 MPa and 138.3 MPa,respectively,and the fatigue strength of sheet after chemical milling was 9.9%lower than that before chemical milling.