Nb相增塑核壳结构TiAl/Nb复合材料的制备及组织性能研究  

Preparation,microstructure and properties of Nb phase plasticized TiAl/Nb composites with core-shell structure

作　　者：申景园 胡连喜[1] 王皓洋 SHEN Jingyuan;HU Lianxi;WANG Haoyang(National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin 150001,China)

机构地区：[1]哈尔滨工业大学金属精密热加工国家级重点实验室,哈尔滨150001

出　　处：《粉末冶金材料科学与工程》2023年第5期481-489,共9页Materials Science and Engineering of Powder Metallurgy

基　　金：国家自然科学基金资助项目(52175295)。

摘　　要：针对传统γ-TiAl合金室温塑性低、难以满足工程化应用的难题,本文提出Nb相增塑核壳结构TiAl/Nb复合材料,系统研究了复合材料的制备工艺和力学性能。结果表明:在200 r/min转速下球磨120 h可实现细小Nb颗粒对大尺寸γ-TiAl雾化粉的完全包裹,随后在40 MPa下,1 200℃真空热压1 h可获得增塑相可控的致密核壳结构组织。制备的TiAl/Nb复合材料在室温下的屈服强度为971.5MPa,抗压强度为2 337.7 MPa,断裂应变为31.7%,表现出高强度和良好的塑性。这种强度和塑性的协同提高归因于延性β-Nb相促进了基体相之间的协调变形,提高了材料的整体持续变形能力。In response to the challenges of the low plasticity at room temperature and difficulty in meeting engineering applications in traditional γ-TiAl alloys,this paper proposed Nb phase plasticized TiAl/Nb composites with core-shell structure,and systematically studied the preparation technology and mechanical properities of the composites.The results show that complete encapsulation of large-sized γ-TiAl atomized powder by fine Nb particle can be achieved after 120 h ball milling at the speed of 200 r/min.Subsequently,a densified core-shell structure with controllable plasticized phase can be obtained after vacuum hot pressing at 1200℃/1 h,under 40 MPa.The prepared TiAl/Nb composites exhibit high strength and good plasticity with the yield strength of 971.5 MPa,compressive strength of 2337.7 MPa,and fracture strain of 31.7%at room temperature.The high strength and excellent plasticity of the composites are attributed to the ductileb-Nb phase which facilitates coordinated deformation between matrix phase colonies,which thereby enhancing the continuous deformation capacity of the integral bulk materials.

关 键 词：球磨 热压 核壳结构 TiAl/Nb复合材料 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]