共查询到20条相似文献,搜索用时 62 毫秒
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应用放电等离子烧结(SPS)技术,利用WO3、Co3O4和C粉的混合粉末原位还原、化合反应快速制备WC6Co硬质合金。分析了烧结温度与压力对合金致密度、显微组织和性能的影响.结果表明:应用SPS技术,利用原位反应合成的短流程工艺路线,在烧结温度与压力分别为1270℃和90MIa的条件下能够快速制备出相对密度达99%、洛氏硬度(HRA)≥93、维氏硬度(HV)≥1900且成相良好、显微组织均匀的WC-Co硬质合金。 相似文献
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将纳米级A12O3以体积分数为1%的配比与微米级Cu粉混合均匀后,采用放电等离子烧结(SPS)法,分别在750、800和850℃进行烧结制备复合材料;将同样的混合粉末采用冷压烧结制备复合材料作为对比.分别测试材料的密度、硬度、导电率,并进行SEM扫描电镜分析.结果表明:在所选择试验参数下,烧结温度为800℃ SPS烧结试样具有最高的相对密度,达到99.17%,硬度与导电率也最高;与冷压烧结制备的材料相比,SPS法制备的试样硬度和导电率更高;SPS烧结试样晶粒均匀细小,并出现了孪晶. 相似文献
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以TiO、TiC和TiN的商业粉末为原料,采用放电等离子烧结技术(SPS)在1 600℃制备致密的钛固溶体Ti3OCN,系统研究了不同烧结方式下(包括SPS、传统烧结(CS)和它们的组合)烧结Ti3OCN的致密化过程和性能变化。结果表明,制备的Ti3OCN具有面心立方结构,其形成机理是O、N元素进入TiC。在SPS之后进行的CS过程可以小范围地增加钛固溶体的密度和电导率,但会降低其机械性能。 相似文献
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电火花烧结的发展趋势 总被引:7,自引:0,他引:7
电火花烧结技术是一种新型的快速烧结技术。具有升温速度快、烧结时间短、效率高等特点。它是通过瞬间高能脉冲电流使粉末颗粒之间产生等离子放电,烧结制成高性能材料或制件。该文综述了电火花烧结的设备、工艺特点和技术原理;分析了电火花烧结的工艺参数对所制得材料的结构和性能的影响;简要介绍了电火花烧结技术在新材料制备及合成中的应用;展望了电火花烧结技术的发展前景。 相似文献
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V. N. Chuvil’deev A. V. Nokhrin G. V. Baranov M. S. Boldin A. V. Moskvicheva N. V. Sakharov D. N. Kotkov Yu. G. Lopatin V. Yu. Belov Yu. V. Blagoveshchenskii N. A. Kozlova D. A. Konychev N. V. Isaeva 《Russian Metallurgy (Metally)》2014,2014(3):215-228
The structure and mechanical properties of nano- and ultradispersed mechanically activated heavy W-Ni-Fe and W-Ni-Fe-Co tungsten alloys (VNZh and VNZhK alloys, respectively) are studied. Mechanically activated nano- and ultradispersed charge powders are sintered by free sintering (thermally activated) and spark plasma sintering. The dependence of the density of the alloys made of the mechanically activated powders on the sintering temperature is found to have a nonmonotonic character with a maximum corresponding to the optimum sintering temperature. It is shown that an increase in the mechanical activation time and the acceleration of the milling bodies during mechanical activation lead to a decrease in the alloy particle size and the formation of nonequilibrium solid solutions and are accompanied by a decrease in the optimum sintering temperature of heavy tungsten alloys. Ultrahigh-strength tungsten alloys the mechanical properties of which are substantially higher than those of standard coarse-grained analogs are fabricated due to the optimization of the conditions of ball milling and high-rate spark plasma sintering of W-Ni-Fe powders. 相似文献
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采用不同的烧结温度和烧结压力对Ti-6Al-4V-0.5In钛合金汽车零件试样进行放电等离子烧结处理,研究了烧结工艺对试样耐磨损性能和冲击性能的影响。结果表明:随烧结温度的提高和烧结压力的增大,试样的耐磨损性能和冲击性能均先提高后下降。钛合金汽车零件材料的烧结温度优选为875℃,烧结压力优选为45 MPa。 相似文献
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采用喷雾干燥法制备了一种球形氧化钛团聚粉末, 并通过高温烧结及感应等离子球化工艺对团聚粉末进行
致密化处理。 利用扫描电子显微镜 (SEM)、 霍尔流速计和粉末颗粒强度仪对粉末性能进行了表征, 研究了不同致
密化处理工艺对粉末颗粒强度、 松装密度及流动性的影响。 采用大气等离子喷涂 (APS) 工艺制备了氧化钛涂层,
并对涂层的微观组织进行研究。 研究结果表明, 高温烧结工艺及等离子球化工艺均可有效提升氧化钛团聚粉末
的致密度, 经过高温烧结工艺后氧化钛粉末内部的细小颗粒呈现烧结熔融的趋势, 而采用等离子球化处理后的
团聚粉末直接形成了致密球体结构。 相比于高温烧结工艺, 等离子球化工艺对氧化钛粉末的致密化效应更为明
显, 粉末的颗粒强度可达 187.86 MPa, 松装密度可由 0.79 g/cm3 提升至 1.69 g/cm3, 流动性由 163.22 s/50g 加快
至 100.27 s/50g。 该粉末经过大气等离子喷涂沉积形成的氧化钛涂层孔隙率为 2.8 %, 与未经致密化工艺处理的氧
化钛团聚粉末相比, 制备的涂层致密化水平有了较大程度的提升, 涂层的平均显微硬度值由 434.18 HV0.3 提升至
744.37 HV0.3, 涂层的结合强度均值由 11.07 MPa 提升至 29.93 MPa。 相似文献
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Li X. Y. Zhang Z. H. Cheng X. W. Huo G. J. Zhang S. Z. Song Q. 《Powder Metallurgy and Metal Ceramics》2021,60(7-8):410-438
Powder Metallurgy and Metal Ceramics - Spark plasma sintering (SPS) is a type of pulsed electric current-assisted sintering technique. This method allows for rapid consolidation of powder materials... 相似文献
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以萘为造孔剂, 采用放电等离子烧结技术(spark plasma sintering, SPS)制备多孔镁块体材料。结果表明, 采用放电等离子烧结技术在470℃时可以制备出结构与尺寸可控性好、开孔率与孔隙率(44.25%)较高、粉体颗粒无明显长大的多孔金属镁块体材料。升华性造孔剂可对孔隙体积进行有效调节, 实现多孔镁材料体内小孔与大孔的合理搭配, 进一步改善多孔镁材料孔隙之间的连通性。将升华性造孔剂与放电等离子烧结技术相结合后, 对于开孔性与颗粒连接性要求较高的多孔金属材料制备具有技术优势, 并对解决传统造孔剂法制备生物多孔金属材料所面临的二次污染问题具有很好的借鉴意义。 相似文献
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Bulk Sm2Fe17Nx sintering magnet was fabricated by spark plasma sintering(SPS) technique. The effects of sintering pressure and sintering temperature on the magnetic properties of the Sm2Fe17Nx magnet were investigated. As a result, the density of the magnet is obviously improved with the increase of sintering pressure, but the coercivity drops since Sm2Fe17Nx has decomposed into SmN, α-Fe and N2. When sintering temperature was only above 200 ℃ under 1 GPa sintering pressure, the coercivity even begins to decrease, which indicates that high pressure promotes the decomposition of the Sm2Fe17Nx at lower temperature. The decomposition is also proved by the decrease of nitrogen and increase of α-Fe in the magnets. 相似文献
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《粉末冶金学》2013,56(2):100-102
AbstractThe performance of diamond/nickel metal matrix composites (MMCs) produced using a novel microwave plasma technique, rapid discharge sintering (RDS), and conventional tube furnace sintering in argon is compared. The MMCs were sintered at temperatures between 850 and 1050°C in both cases. The RDS treatments were carried out at 20 mbar in plasmas containing hydrogen or hydrogen–nitrogen gases. The addition of nitrogen gas to the hydrogen plasma facilitated a substantial increase in composite firing temperatures. A significant reduction in sintering times, to 10 min from several hours, was achieved using the RDS technique. A further advantage of the RDS treatments was the absence of any diamond graphitisation (as detected by X-ray diffraction), which was reflected in higher sintered densities and flexural strength for RDS than for furnace sintering. 相似文献