深度冷旋对超薄壁大径厚比镍基合金焊接筒性能的影响

Effect of Deeply Cold Spinning on Properties of Ultra-Thin-Wall Large Radius-Thickness Ratio Nickel-Based Alloy Welded Cylinder

对C-276镍基合金薄壁大径厚比焊接筒形件进行深度冷旋,获得直径为φ558mm、壁厚为0.42mm的超薄壁筒;通过拉伸试验、显微组织观察、腐蚀性能试验等分析了深度冷旋对基体与焊缝力学性能、显微组织以及耐腐蚀性能的影响。结果表明:冷旋减薄80%后,基体晶粒明显细化,取向性增强,焊缝晶粒由粗长的鱼骨状枝晶变成小颗粒状晶粒;冷旋减薄80%+1150℃固溶退火后,基体晶粒与冷旋前相近,抗拉强度基本保持不变,伸长率提高了23.28%,而焊缝晶粒比基体的更加细化,抗拉强度超过了基体的,较冷旋前提高了10.11%,伸长率提高了43.6%,焊缝和热影响区的耐腐蚀性能得到了改善。

The ultra-thin-wall cylinder, which owned radius of 558 mm and wall thickness of 0. 42 mm, was obtained by deeply cold spinning on C-276 nickel-based alloy thin-wall large radius-thickness ratio welded cylinder： The effect of deeply cold spinning on mechanical properties, microstructure and corrosion resistance of matrix and weld seam by tensile test, microstructure observation and corrosion test. The results show that the grains in matrix were refined obviously and the orientation of grains was enhanced after cold spinning reduced by 80 %, and the grains in weld seam transformed into small granular grains from coarse and long fishbone dendrite. After cold spinning reduced by 80% and solution annealing at 1 150℃, the grains in matrix were similar with those before cold spinning, tensile strength kept invariant and elongation raised by 23. 28%. The grains in weld seam were smaller than those in matrix, tensile strength was higher than that of matrix and increased by 10. 11%and elongation increased by 43. 6%, the corrosion resistance of weld seam and heat affected zone were improved.