冷轧与拉伸复合预变形对2519A铝合金板材应力腐蚀的影响(英文)

Effect of pre-deformation of rolling combined with stretching on stress corrosion of aluminum alloy 2519A plate

采用10-6s-1慢应变拉伸测试手段研究冷轧与拉伸复合预变形对2519A铝合金抗应力腐蚀开裂性能的影响。冷轧7%后再垂直拉伸3%的合金板材抗拉强度和应力腐蚀指数分别为481MPa和0.0429,与冷轧4%后再平行拉伸3%以及冷轧7%后再平行拉伸3%的合金板材相比表现出了更好的力学性能和抗应力腐蚀开裂性能。这主要是由于冷轧7%后再垂直拉伸3%在合金板材中生成了密度更高且分布更均匀的位错组织,使时效后合金板材晶内析出相细小、密集,晶界析出相不连续,晶界无沉淀析出带且较窄。

The effect of the pre-deformation of rolling combined with stretching on the stress corrosion cracking resistance of aluminum alloy 2519A was studied by means of the slow strain rate technique at 10-6 s-1. The tensile strength and stress corrosion index of the alloy plate with 7% rolling plus 3% perpendicular stretching were 481 MPa and 0.0429, respectively, showing better mechanical property and stress corrosion cracking resistance than those with 4% rolling plus 3% parallel stretching or 7% rolling plus 3% parallel stretching, which is due to its finer and denser precipitates within the grains, discontinuous grain boundary precipitates, as well as more narrow precipitate-free zone width. Such microstructure is attributing to the denser and more homogeneously distributed dislocations which are produced by the pre-deformation.