化学配比对TiAl有序合金微观组织和变形特性的影响

来源期刊：中南大学学报(自然科学版)1992年第6期

论文作者：曲选辉 黄伯云 吕海波 黄培云

文章页码：706 - 711

关键词：钛化合物; 金属间化合物; 显微组织; 位错; 延性/铝化物; 有序合金

Key words：titanium compounds; intermetallic compounds; microstructures; dislocations; ductility/aluminides; ordered alloys

摘    要：本研究用三点弯曲实验测定了铝含量为43at·%～56at·%的Ti-Al二元合金的力学性能;利用光学显微镜、X射线衍射仪和透射电子显微镜研究了不同成分合金的微观组织和变形亚结构.实验结果表明:根据不同成分合金的微观组织可将其分成三类,即:γ-TiAl单相组织(52at·%～56at·%Al);双态组织(46at·%～50at·%Al)和全片层结构晶粒组织(43at·%～46at·%Al),其中以具有细晶双态组织的合金具有较好的塑性变形能力.本文从微观组织结构和变形位错组态的变化,探讨了合金成分对TiAl基有序合金塑性变形的影响机制.

Abstract: The mechanical properties of binary TiAl-base alloys with Al contents from43at% to 56 at.% were measured with bending test. Their microstructures anddeformation substructures were studied by means of optical microscope, X-raydiffractometer and transmission electron microscope. It was found that the alloys could be classified into three groups according to their microstructuralcharacteristics, i.c., γ-TiAl single phase structure (52at·%～56at·%Al), duplexstructure(46at·%～50at. %Al)and full lamellar structure(43at·%～46at·%). Amongthese three groups of alloys, only the alloys with fine duplex structure showappreciable plastic strains. In this paper, the compositional effect on the plasticdeformation of TiAl-base ordered alloys were discussed in view of the changesin microstructures and deformation dislocation configurations with composition.