Effects of pass deformation rate on microstructure and tensile property of cold rolled TA18 alloy tubes were studied. The microstructure was observed by optical microscope and tensile properties were evaluated by using a tensile tester. The result shows that the microstructure of cold rolling TA18 alloy tube is bacillarstructure and the crystal preferred orientation becomes more significant with increasing the pass deformation rate from about 35% to 50%. At the same time, the tensile strength of TA18 alloy tube increases but the strain remarkably decreases. The microstructure of the tube turns to equiaxed crystal after annealing at the temperature of 750 t. Then both the tensile strength and the strain of the tube increase because of fine grain strengthen. The TA18 alloy tube' s tensile properties at the first and the second cold rolling pass are similar to the third and the forth pass. Thus, it' s possible to realize tandem rolling of TA18 alloy tube to simplify the production flow.%改变冷轧道次变形率研究其对TA18钛合金管材组织和拉伸性能的影响.用金相显微镜观察了其微观组织形貌,用Instron 1185拉伸试验机测试了拉伸性能.结果表明:冷轧态TA18钛合金管材显微组织为纤维状；冷轧第三、四道次管材的晶粒取向程度弱于第一、二道次,抗拉强度和屈服强度较低,但延伸率大幅提高；经过750℃/90 min再结晶退火后所有TA18管材晶粒为等轴状晶粒,组织取向消失,同时由于细晶强化作用,使第一、二道次退火后的TA18钛合金管材保持了相对较高的强度和延伸率.由于第三、四道次冷加工态性拉伸能指标与第一、二道次退火态较为接近,因此存在通过连轧的方式来简化工艺流程的可能.
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