不同变质剂对4032铝合金变质效果的影响

研究Sr与不同变质剂复合添加对4032铝合金组织及性能的影响.通过组织观察、扫描电镜观察、能谱分析和力学性能测试发现:在几种不同的变质体系中,Sr与Na盐复合变质后的组织和性能最好;Sr+其他元素复合变质的针孔率低于Sr单独变质处理的针孔率,其中以Sr+Na盐变质的针孔率最低;共晶型铝硅合金添加Sr和Na变质组织呈亚共晶状态,而经P变质后组织呈过共晶状态.     

Modification performance on 4032 Al alloy by using Al–10Sr master alloys manufactured from different processes

The microstructures and modification performance on 4032 aluminum alloy of the Al–10Sr master alloy wire prepared from "direct reaction-hot extrusion" and the trapezoidal block from "direct reaction" were systemically studied by using optical metallurgical microscope, XRD and SEM. It was found that the preparation processes exhibited a significant effect on the microstructures of the Al–10Sr, which thereby influenced its modification performance. It has been found that when the Al–10Sr alloy wire was used, a desirable modification was obtained after 2 min and reached to the best performance at 60 min, and the optimum Sr addition amount was 0.04–0.06 wt%, and the good modification performance was kept even after 300 min. However, when the Al–10Sr alloy trapezoidal block was used, a desirable modification was started after 30 min and reached to the best performance as long as 120 min, and the optimum Sr addition amount was 0.06–0.08 wt%, and the effective modification period was only180 min. Therefore, comparing with the Al–10Sr alloy trapezoidal block, the Al–10Sr alloy wire had better modification efficiency, which not only reduced the Sr addition amount of about 30%, but also greatly decreased the incubation time and improved the ability of anti-fading.     

钎焊金刚石砂轮磨削AA4032铝合金试验

通过磨削试验,研究钎焊金刚石砂轮磨削4032铝合金(AA4032)在不同磨削参数时的磨削特性.结果表明:磨削力和磨削表面粗糙度都随着磨削深度和工件进给速度的增加而增大,随着砂轮线速度的增加而减小;法向磨削力与切向磨削力有良好的线性关系,其力比为2.6;AA4032主要以塑性方式去除,其被加工表面由光滑区、划痕、磨屑粘附、白色析出颗粒及孔组成,表面质量随磨削速度增大而明显提高;磨削比能随单颗磨粒切削厚度(h_c,max)增大而减小,在相同h_c,max下,高速磨削有利于降低磨削能耗.