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通过粉末冶金方法制备适合于高压封垫材料的W-Ti合金,其中选择W以及Ti或TiH_2为原始粉末,采用行星球磨机球磨,然后经成形和真空烧结得到最终W-Ti合金。利用激光粒度仪、X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)等手段,研究W-Ti和W-TiH_2体系在球磨过程中粉末的形貌、粒度、粒度分布、合金化程度及其对合金组织的影响。结果表明,两个体系混合粉末球磨12.0 h后,W-TiH_2混合粉末的中位径达到1.31μm,约为W-Ti混合粉末的中位径(13.01μm)的10%,因为细小而硬的W粉颗粒促进粗而脆的TiH_2粉末的破碎,使整体粉末粒度变细,呈等轴颗粒状,但对粗而软的Ti粉的破碎没有作用,反而嵌在片状Ti粉上使整体粒度变粗;W-TiH_2混合粉末球磨12.0 h后,中位径由原始的10.87μm急剧降低到1.31μm,再延长球磨时间中位径变化缓慢;随着球磨时间延长到22.0 h,W-TiH_2混合粉末中TiH_2分解与W形成Ti_xW_(1-x)固溶体,同时TiH_2粉与Ti_xW_(1-x)固溶体向纳米级细化,烧结后更容易得到均匀细小的合金组织。
A W-Ti alloy suitable for high-pressure gasketing material was prepared by powder metallurgy. W and Ti or TiH 2 were selected as raw powders, ball-milled by planetary ball mills and finally formed and vacuum-sintered to obtain the final W-Ti alloy. The morphology, particle size and particle size distribution of W-Ti and W-TiH_2 systems during ball milling were studied by means of laser particle size analyzer, X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) , The degree of alloying and its effect on the alloy structure. The results show that the median diameter of the W-TiH 2 powder reaches 1.31μm after ball milling for 12.0h, which is about 10% of the median diameter (13.01μm) of the W-Ti mixed powder. Because of the small and hard W powder particles to promote rough and brittle TiH2 powder crushing, the overall powder particle size becomes thin, was equiaxed granular, but the coarse and soft Ti powder crushing no effect, but instead embedded in the sheet Ti powder so that the overall size The mean diameter of W-TiH_2 powder decreases sharply from 10.87μm to 1.31μm after ball milling for 12.0h, and the ball diameter changes slightly after ball milling. With the milling time prolonged to 22.0h, the W-TiH_2 TiH 2 powder decomposes with W to form Ti_xW_ (1-x) solid solution. At the same time, the TiH_2 powder and Ti_xW_ (1-x) solid solution are refined to nano-scale, and the uniform and fine alloy structure can be obtained easily after sintering.