冷喷涂Ti-Al复合材料的搅拌摩擦加工改性研究  

Modification of Cold Sprayed Ti-Al Composites by Friction Stir Processing

作　　者：刘杨 徐雅欣 李文亚[1] LIU Yang;XU Yaxin;LI Wenya(School of Material Science and Engineering,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]西北工业大学材料科学与工程学院,西安710072

出　　处：《表面技术》2025年第3期210-219,共10页Surface Technology

基　　金：航空发动机及燃气轮机基础科学中心重点项目(HT-P2022-B-Ⅳ-011-001)。

摘　　要：目的解决冷喷涂直接沉积钛铝金属间化合物时因金属颗粒硬脆而出现的沉积率极低或无法沉积等问题,针对增材制造钛铝合金的需求,采用冷喷涂和搅拌摩擦加工相结合的方法原位制备钛铝金属间化合物。方法采用纯铝板为冷喷涂基板,经冷喷涂沉积纯Ti、Al后得到预沉积体,对已沉积的Ti-Al复合材料进行不同参数的搅拌摩擦加工后制备出试样,并采用光镜、扫描电镜、X射线衍射、硬度测试对比研究不同处理状态复合材料的组织和性能。结果喷涂态沉积体并未形成Ti-Al金属间化合物。经FSP处理后,沉积体中形成了含有细小晶粒的Ti和Ti-Al金属间化合物复合组织。由XRD结果可知,FSP制备的金属间化合物为TiAl3,且复合材料中存在未反应的原始Ti颗粒。冷喷涂沉积体经热处理因Kirkendall效应会产生较大孔隙,但经FSP处理后组织致密,无明显孔隙,硬度显著提高到256HV,复合材料的组织得到细化。结论通过高压冷喷涂技术和搅拌摩擦加工原位制备了组织均匀且致密、内部结合良好的钛铝金属间化合物,并使用优化后的搅拌摩擦工艺参数完成了良好的钛铝金属间化合物的增材制造,达到试验预期要求。Titanium-aluminum alloys are prone to cracks and oxidative inclusions when prepared by the thermal processing-type additive manufacturing technologies.With solid-phase additive manufacturing,the problems of cold spraying(CS)direct deposition of titanium-aluminum intermetallic compounds can be solved,but the metal particles are hard and brittle,resulting in a very low deposition rate or deposition failure,etc.In response to the needs of additive manufacturing of titanium-aluminum alloys,the combination of cold spraying and friction stir processing(FSP)method for the in-situ preparation of the titanium-aluminum is adopted.In order to meet the demand for additive manufacturing of titanium-aluminum alloys,the alloys are prepared in situ by combining cold spraying and friction stir processing.The test materials were pure Ti powder(15-53μm)and pure Al powder(13-38μm),which were mixed and processed by a planetary ball mill for 3 hours(no grinding ball was required)according to the ratio of 35%Ti and 65%Al,to obtain the mixed powder for cold spraying.Pure 1060 aluminum plate was used as the substrate for cold spraying.Before the cold spraying,the surface of the aluminum plate was ultrasonically cleaned by acetone immersion and then sandblasted with Al_(2)O_(3).The pre-deposited body was obtained after the deposition of pure Ti and Al by cold spraying,and the deposited Ti-Al composite was processed by friction stir processing at the same traveling speed and rotational speeds of 800 r/min,1000 r/min,and 1200 r/min.The cold spraying system was developed by Northwestern Polytechnical University,with a Laval nozzle with a throat diameter of 2.5 mm and an outlet diameter of 5 mm,and the accelerating gas and powder feeding gas in the cold spraying process were N2.The friction stir processing was carried out with a Computer Numerical Control friction(CNC)stir processing welding machine,FSE-SD3020T,from Beijing Solidweld Co.In the heat treatment(HT)experiment,the protective gas was argon.The cold sprayed deposit was subject to

关 键 词：原位生成 TIAL复合材料 冷喷涂 搅拌摩擦加工 微观组织 力学性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]