(西北有色金属研究院，西安 710016)
摘 要: 研究采用斜轧穿孔及冷扩成形方法制备直径大于130 mm的大口径Ti-75无缝管材的可行性。分别测试穿孔管坯和冷扩后管材的金相组织、力学性能及沿管材轴向方向的裂纹情况。结果表明：采用斜轧穿孔方式可以制备Ti-75合金大口径无缝管材且拥有较好的塑性；在室温下，进行冷扩，在扩径率小于15%时，可得到抗拉强度为780 MPa，屈服强度为685 MPa，伸长率为13.5%，断面收缩率为55%的管坯，且不出现扩裂等情况。
关键字: Ti-75合金；斜轧穿孔；冷扩成形；大口径；管材
（Northwest Institute for Nonferrous Metal Research, Xi’ an 710016, China）
Abstract:The feasibility of preparation of large-diameter seamless pipe of Ti-75 alloy using rotary piercing and cold expansion method. The microstructure, mechanical properties and crack along the pipe axial direction of the situation of the piercing tube and cold-expanded pipe were tested. The results show that Ti-75 large diameter alloy seamless pipe can be prepared using the rotary piercing method and it has a good plasticity. At room temperature, when the expansion of diameter is less than 15%, the tube with tensile strength of 780 MPa, yield strength of 685 MPa, elongation percentage of 13.5% and contraction of area of 55% can be obtained by cold expansion forming. There is no extending cleft in the tube.
Key words: Ti-75 alloy; rotary piercing; cold expansion forming; large-diameter; pipe
