添加Y元素对Ti-6Al-4V-2Cr-1.5Mo合金组织和力学性能的影响

Effect of Y Addition on Microstructure and Mechanical Properties of Ti-6Al-4V-2Cr-1.5Mo Alloy

摘要: 通过OM、SEM、XRD和TEM对热处理态Ti-6Al-4V-2Cr-1.5Mo-xY(x=0.1,0.5,1.0,1.5,质量分数)合金的组织和力学性能进行分析,发现添加稀土Y元素后,合金的组织得到了明显的细化,产生的稀土氧化物Y₂O₃弥散分布在基体中;且当Y元素的添加量为0.5%时,合金的强度、硬度和伸长率最好,性能最优。对热处理态的Ti-6Al-4V-2Cr-1.5Mo-0.5Y进行分析,发现析出相Y₂O₃与基体α-Ti之间的错配度为0.141 3,属于半共格界面。

Abstract: The microstructures and mechanical properties of Ti-6Al-4V-2Cr-1.5 Mo-xY (x =0.1, 0.5, 1.0, 1.5, mass fraction) alloys are analyzed by means of OM, SEM, XRD, and TEM. It is found out that the microstructures of Ti-6Al-4V-2Cr-1.5 Mo-xY alloys are refined obviously after adding the rare earth Y element, that the Y₂O₃ phases formed are dispersed in the matrix, and that the mechanical properties of the alloy increase first and then decrease with the increase of the content of rare earth Y. The strength, hardness, elongation and properties of the alloy are the best when the addition of Y element is 0.5%. The mismatch between Y₂O₃ and the matrix α-Ti of the annealed Ti-6Al-4V-2Cr-1.5 Mo-0.5 Y is 0.141 3, which belongs to semi-coherent interface.