预变形对TB3合金时效析出行为及其力学性能的影响

Influence of Predeformation on Aging Precipitation Behavior and Mechanical Properties of TB3

摘要:

研究固溶处理后的预变形对Ti-10Mo-8V-1Fe-3.5Al（TB3）随后时效过程中α相析出行为以及时效处理后力学性能的影响。对于经过预变形的试样时效后在金相显微镜下观察到网状的析出组织。透射电子显微镜观察表明：预变形时效试样中，α片优先在滑移带、晶界等高密度位错区形核长大，并伴有α片的变体选择效应。金相与X射线衍射结果表明，预变形对α相变有促进作用。拉伸试验结果显示：与自由时效相比，通过冷变形可以缩短时效时间，提高材料拉伸强度，但同时降低了材料的延性。

Abstract:

The influence of prior cold deformation after solution treatment on the α phase precipitation behavior during the subsequent aging treatment and final mechanical properties of TB3(Ti-10Mo-8V-1Fe-3.5Al) alloys was investigated. In the predeformed samples, network patterns were observed after aging treatment by metallographic microscope. Transmission electron microscopic (TEM) observation shows that in the predeformed-aged samples, the plate-shaped α precipitates prefer to nucleate and grow in high density dislocation sites, such as grain boundaries and slip bands. In addition, variant selection effects were observed in these samples. Results of X-ray diffraction and metallographic microscope indicate that α phase precipitation process could be accelerated in predeformed samples. Tensile test results reveal that by cold deformation the aging time could be shortened and the tensile strength could be enhanced, while the ductility could be reduced, in comparison with the freely aged sample.