Effect of annealing temperature on texture and residual stress of Ti-6Al-4V alloy seamless tubing processed by cold rotary swaging. (July 2020)

• Record Type: Journal Article
• Authors: Yuan, Lihong; Wang, Wenrui; Li, Yun; Yang, Mengyao; Zhang, Hui; Zhang, Wangfeng
• Is Part Of: Vacuum. Volume 177(2020)
• Publication Date: 2020-07
• Subjects: Ti-6Al-4V -- Rotary swaging -- Texture -- Microstructure -- Residual stress; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2020.109399
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: The thin-walled seamless Ti-6Al-4V alloy tubing was prepared by cold rotary swaging (RS) with a 40% wall reduction. The microstructure, texture and residual stress of the tubing samples under different annealing temperatures were investigated. The results show that the grains of the tubing samples after RS are obviously refined and streamlined. The maximum density level displayed in the cut of orientation distribution function (ODF) increases from 4.51 to 8.32, with a basal tilt angle of 10° around the radial direction of the tubing, which indicates that the radial texture of the Ti-6Al-4V alloy tubing become stronger after RS. Additionally, the post-swaging annealing at 400 °C and 500 °C for 2.5 h were adopted to relieve the residual stress of the tubing samples. The former can just relieve at most 80% of the residual stress, while the latter can relieve 97% of the residual stress to achieve an almost stress-free state. Hence, it is thought that the annealing at 500 °C can achieve the better effect to relief the residual stress. Highlights: The thin-walled Ti-6Al-4V alloys seamless tubing can be prepared by cold-RS with wall thickness deformation rate of 40%. Cold rotary swaging can remarkably refine the grain sizes of Ti-6Al-4V alloy tubing in the radial direction. The favorable radial texture of Ti-6Al-4V titanium alloy tubing is formed after RS. . Annealing at 500℃ for 2.5 h can fully eliminate the residual stress of the Ti-6Al-4V tubing without affecting the texture.