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高速壓制法制備W-15Cu合金工藝的研究

發(fā)布時(shí)間:2018-06-23 16:07

  本文選題:W-Cu復(fù)合材料 + 細(xì)顆粒鎢粉; 參考:《中南大學(xué)》2010年碩士論文


【摘要】: 鎢銅合金結(jié)合了鎢的低膨脹性和銅的高熱導(dǎo)性能,是一種具有優(yōu)良的導(dǎo)熱性能和可調(diào)節(jié)的熱膨脹系數(shù)的電子封裝復(fù)合材料。目前鎢銅合金的生產(chǎn)主要采用熔滲法。而在熔滲法制備W85-Cu合金的過(guò)程中,采用細(xì)鎢粉制備的鎢銅合金與采用粗粒度鎢粉制備的鎢銅合金相比組織更均勻,產(chǎn)品性能也更好,目前國(guó)外生產(chǎn)鎢銅復(fù)合材料一般采用細(xì)鎢粉作為原料。但以細(xì)鎢粉為原料,采用傳統(tǒng)壓型工藝很難得到相對(duì)密度達(dá)到72.40%的細(xì)鎢粉骨架,因而得不到成分為W85-Cu的合金。本實(shí)驗(yàn)中采用高速壓制技術(shù)(HVC)成功獲得相對(duì)密度達(dá)到72.40%的細(xì)鎢粉骨架,再通過(guò)熔滲工藝制備出高性能的細(xì)粉W85-Cu合金,并在熔滲后采用鍛造的方法進(jìn)一步提高鎢銅合金的密度。本論文研究?jī)?nèi)容主要包括鎢粉末直接高速壓制工藝的研究,鎢預(yù)成型坯高速壓制工藝的研究,鎢銅合金熱鍛工藝的研究,并借助各種實(shí)驗(yàn)手段對(duì)材料的組織和性能進(jìn)行了分析,主要結(jié)論如下: 1)在摻入一定量的SBP膠之后,采用粉末直接高速壓制可以得到鎢高速壓制坯,鎢粉粒度越粗、鎢粉的能量密度越高,所得到的鎢高速壓制坯的密度也越高; 2)通過(guò)鎢預(yù)成型坯的高速壓制得到的壓坯密度與粉末粒度、預(yù)成型坯密度、壓制溫度以及能量密度有關(guān):粉末粒度越粗、預(yù)成型坯密度越高、壓制溫度越高、能量密度越大,所得到的鎢高速壓制坯密度越高。 3)通過(guò)熱鍛可以進(jìn)一步提高細(xì)鎢粉鎢銅合金的密度,熱鍛溫度越高,合金的密度提高越大,對(duì)于近致密鎢銅合金,多次熱鍛密度提高不明顯。 4)通過(guò)限位在950℃時(shí)對(duì)鎢預(yù)成型坯進(jìn)行高速壓制可以獲得相對(duì)密度為72.40%的細(xì)鎢粉骨架,經(jīng)熔滲后可以得到相對(duì)密度達(dá)到99%以上的W85-Cu復(fù)合材料;熱導(dǎo)為177W/(m·K),熱膨脹系數(shù)(150℃)為6.9×10-6/K,氣密性指標(biāo)(He吸附)為1.0x10-9Pa·m3·s-1,各項(xiàng)性能都達(dá)到相應(yīng)熱沉材料的要求。
[Abstract]:Tungsten copper alloy is a kind of electronic packaging composite with excellent thermal conductivity and adjustable thermal expansion coefficient, which combines the low expansion property of tungsten with the high thermal conductivity of copper. At present, the production of tungsten-copper alloy mainly adopts infiltration method. However, in the process of preparing W85-Cu alloy by infiltration, the microstructure and properties of W85-Cu alloy prepared by fine tungsten powder are more uniform than those prepared by coarse-grained tungsten powder. At present, tungsten powder is generally used as raw material in the production of tungsten-copper composites abroad. However, it is difficult to obtain the skeleton of tungsten powder with relative density of 72.40% by traditional pressing technology, so the alloy containing W85-Cu can not be obtained. In this experiment, the high speed pressing technique (HVC) was used to obtain the fine tungsten powder skeleton with relative density of 72.40%, and then the high performance fine powder W85-Cu alloy was prepared by infiltration process, and the density of tungsten and copper alloy was further improved by forging after infiltration. This paper mainly includes the research of direct high speed pressing technology of tungsten powder, the study of high speed pressing technology of tungsten preformed billet, the research of hot forging technology of tungsten copper alloy, and the analysis of the microstructure and properties of the material by various experimental means. The main conclusions are as follows: 1) the higher the particle size of tungsten powder, the higher the energy density of tungsten powder. The density of high speed pressed tungsten billet is also higher. 2) the density of compacted billet and powder particle size obtained by high speed compaction of preformed tungsten billet, the density of preformed billet, Compacting temperature and energy density are related: the coarser the powder size, the higher the preform density, the higher the pressing temperature, the higher the energy density, The density of tungsten high speed pressed billet is higher. 3) the density of tungsten powder tungsten copper alloy can be further increased by hot forging. The higher the hot forging temperature, the higher the density of alloy, for the near dense tungsten copper alloy, The density of tungsten powder is not obviously increased by multiple hot forging. 4) the skeleton of fine tungsten powder with relative density of 72.40% can be obtained by pressing tungsten preformed at 950 鈩,

本文編號(hào):2057686

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