固溶处理对TA15X钛合金钻杆材料组织与性能的影响

Effect of solution treatment on microstructure and properties of TA15X titanium alloy drill pipe materials

通过力学性能测试、SEM断口分析、OM金相观察等方法,研究了油气工业用TA15X钛合金钻杆材料的固溶工艺及其组织性能变化.结果表明:随着固溶温度的升高,空冷后合金中α相体积分数由68.3%下降到28.2%,相尺寸逐渐减小,晶界α相消失,片层组织演化为近网篮组织.抗拉强度和屈服强度变化不大,延伸率下降至8.5%;水冷后β相转变的针状马氏体α′体积分数由30.5%增加到36.7%,且针状马氏体α′尺寸变得细长.抗拉强度由950 MPa提高至1 145 MPa,屈服强度由860 MPa提高至954 MPa,延伸率下降至5.5%.当固溶温度为900℃的时候,强度提高100 MPa,空冷后延伸率也可达13%,强韧性匹配较好.

The solid solution process of TA15X titanium alloy,a drill pipe material for oil and gas industry,and its microstructural and property changes were studied via mechanical property test,SEM fracture analysis,and OM metallographic observation.The results show that with the increase of solution temperature,αphase in the alloy after air cooling becomes thinner and shorter and its content decreases from 68.3%to 28.2%.The tensile strength and yield strength change marginally,while the elongation decreases to 8.5%.The content of more slender acicular martensiteα′formed from theβphase transition after water cooling increased from 30.5%to 36.7%.The tensile strength increased from 950 MPa to 1145 MPa,the yield strength increased from 860 MPa to 954 MPa,and the elongation decreased to 5.5%.At solution temperature of 900℃,the strength was increased by 100 MPa,and the elongation after air cooling can reach 13%,abtaining a well match of strength and toughness.