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金属粉末注射成形模具浇口对成形性能的影响规律 总被引:2,自引:0,他引:2
根据金属粉末注射成形原理,在材料、模具温度等试验条件一致的前提下,将螺旋测试模与0.5~2.1mm之间的6个不同深度尺寸的侧浇口相结合,通过改变注射料熔体温度、注射压力、注射速率等工艺参数,描绘出在不同工艺参数时的侧浇口深度尺寸与阿基米德螺旋线长度的关系曲线,从而研究得到金属粉末注射成形的浇口尺寸与注射料熔体注射成形性能的关系规律:浇口尺寸对金属粉末螺旋线流动长度的影响较大,且不成比例;浇口尺寸与螺旋线流动长度关系曲线(L—H曲线)的变化不是单调的递增或递减,曲线形状呈较为明显的“波浪”形;在一定试验条件下粉末注射成形的理想浇口尺寸值为1.8mm,要偏大于注塑成形的浇口尺寸值;相对注射压力变化时浇口尺寸对L—H曲线关系的影响而言,注射料熔体温度和注射速率的影响相对较小,波动方向一致且较平坦,曲线有微小的上升趋势;当浇口尺寸一定时,工艺参数对流动长度的影响规律与注塑成形中工艺参数的影响规律类似。 相似文献
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比较了用快淬法、HDDR法、机械合金化法、和气体雾化法生产NdFeB水磁体的制备方法及其特点,指出采用气体雾化制备的磁粉较适宜于注射成形生产;对注射成形生产烧结NdFeB水磁体时枯结剂、成形及取向、脱脂和烧结工艺参数进行了总结,介绍了热塑性体系和水溶性体系枯结剂在注射NdFeB烧结磁体中的应用;将注射成形和传统模压成型的NdFeB磁体性能进行了对比;在分析现状的基础上,指出了现阶段存在的问题和发展方向。 相似文献
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高比重钨合金的金属注射成形技术 总被引:4,自引:0,他引:4
概述了金属注射成形技术的基本工艺过程及其特点,从几种金属注射成形典型工艺分析入手介绍了金属注射成形技术的发展状况,最后介绍了该技术在高比重钨合金中的应用。 相似文献
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近年来,粉末注射成形技术作为一种先进的成形方法受到广泛的关注,得到了迅速的发展.本文综述了粉末注射成形技术的工艺特点、技术现状以及在硬质合金异型产品制备中的应用,并对硬质合金注射成形技术的发展方向和前景进行了展望. 相似文献
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粉末注射成形是制造复杂形状钛及钛合金零件的合适工艺。本文利用氢化脱氢(HDH)钛粉制备注射成形纯钛材料,研究了溶剂脱粘、热脱粘和真空烧结工艺对粘结剂脱除率、烧结显微组织和力学性能的影响。结果表明:溶剂脱粘的适宜温度为50~60℃,4h后可以脱除97%以上的可溶性粘结剂;在随后的真空热脱粘过程中,在200-450℃高温阶段降低升温速率、延长保温时间,有利于脱除剩余聚合物粘结剂;真空烧结温度为1250℃时,烧结致密度可高达98%,但表层易形成硬质TiC相和微量TiO2相;在该温度下烧结1.5h,制品抗拉强度和伸长率分别提高到349MPa和6.4%,继续延长烧结时间会导致拉伸性能下降。 相似文献
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实验结果表明,M17铸造高温合金(%:0.16C、8.79Cr、5.79A1、4.93Ti、3.29Mo、15.20Co、0.78V、0.015B、0.073Zr、0.002S、0.001P、0.001 1O、0.001 0N)经25 kg真空感应炉返回重熔后,Si含量随重熔次数的增加而略有增加,合金中主要元素和其它杂质元素S、P、H的含量变化不大,而氧、氮略有增加;合金中初生碳化物由新合金中的草书体逐渐向返回合金块状转变,初生碳化物的遗传性堵塞合金凝固时的补缩通道,使返回料合金的疏松倾向增大,高温塑性下降较大。 相似文献
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<正>Minmetals Resources acquired the world’s largest copper mine under construction for USD5.85 billion.One after another,listed companies Jien Nickle,China Molybdenum and Chihong Zinc and Germanium raised money to get involved in overseas mining projects…SOEs and private enterprises are engaged in a frenzy of overseas mine purchasing.A reporter with Economic 相似文献
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正Judging from China’s copper consumption field,the biggest consumption unit is electric power,which accounts for 47%of total consumption;it is followed by light industry sector,including household electrical appliance,machinery,durable goods and hardware etc,which accounts for 22%of total consumption;followed by transportation field, 相似文献
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《China Nonferrous Metals Monthly》2014,(10)
正In 2013,the Central Geological Prospecting Fund(CGPF)Project newly discovered 15 ore fields,including 3 large above ore fields,and 5medium sized ore fields.The reporter learned from the recently published"Annual Report of Central Geological Prospecting Fund Project(2013)"that,from 2006 to 2013 the CGPF 相似文献
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《China Nonferrous Metals Monthly》2014,(10)
正This year,the investment growth rate of real estate industry continued to slow down,sold area of commercial housing also dropped significantly,which brought huge pressure to the domestic air conditioning manufactures.In the first half of the year,by relying on high growth in national financial expenditure,along with investment in public infrastructure 相似文献
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《China Nonferrous Metals Monthly》2014,(10)
正Kang Yi,Honorary Chairman of China Nonferrous Metals Industry Association,said recently at the Forum on Development of the Non-ferrous Metals Industry in Central and Western China held in Zhengzhou that,as more and more electrolytic aluminum factories in Xinjiang came into operation,the electrolytic aluminum output of Xinjiang had reached2,275,000 tons in the first 7 months this year, 相似文献
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《China Nonferrous Metals Monthly》2014,(12)
正"Xinjiang project has been completed according to schedule,but total completion and total start of production are two different concepts,after completion it still needs a gradual process of reaching production target."On the morning of November 3,Shenhuo Coal Industry and Electricity Power told investors the above statement on the investor interaction platform. 相似文献
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正The reporter learned from Guangdong Province Precious Metal Transaction Center that in 2013the Center maintained healthy development momentum,and had become the second largest precious metal transaction platform in China in terms of market size;currently Guangdong is quickening steps of financial innovation for the Center,aiming to build a transaction center with international core competitiveness. 相似文献