粉末温轧工艺对W-20Cu合金密度和显微组织的影响

Effects of warm rolling processes on density and microstructure of W-20Cu alloy

在W-Cu混合粉末中加入0.1%～2.0%（质量分数）的有机添加剂,在60～150℃温度下温轧成生板坯,然后进行液相烧结,获得W-20Cu合金板材。通过正交试验研究粉末轧制速度、轧制温度与添加剂含量对生板坯密度的影响,并对烧结板材的密度和显微组织进行分析与表征。结果表明,轧制温度与添加剂含量对粉末轧制板坯密度有显著影响,二轧制速度对生板坯密度的影响较小。随轧制温度升高,W-20Cu生板坯的密度增大,烧结板材的孔隙尺寸逐渐减小,孔隙率逐渐降低,烧结密度相应提高;随添加剂含量增加,板坯密度先升高后降低。在轧制温度为150℃,添加剂含量为0.3%时,生板坯的相对密度达到最大值85.38%,液相烧结后获得相对密度为99.65%的W-20Cu合金板材,金属Cu元素在钨基体中均匀、弥散分布。

W-Cu powder mixtures were added with 0.1%-2.0% （mass fraction） organic additives, then warm rolled into green strips at 60-150 ℃, and finally suffered liquid-phase sintering to prepare W-20Cu alloy strips. The effects of rolling speed, rolling temperature and additive content on green strips density were studied by orthogonal experiments, and the density and microstructure of the sintered alloy strips were also analyzed and characterized. The results show that the density of W-20Cu alloy green strips are significantly affected by rolling speed and additives content, while little affected by rolling speed. With increasing rolling temperature, the density of W-20Cu alloy green strips increases, the pore size of sintered strips reduces and the porosity decreases. With increasing additives content, the density of green strips increases first and then decreases. Under the conditions of rolling temperature at 150 ℃ and with 0.3% additives content, the W-20Cu alloy green strips reach the maximum relative density of 85.38%, and W-20Cu alloy strips with 99.65% relative density are prepared after the liquid-phase sintering. Copper element exhibits homogeneous and dispersed distribution in the tungsten matrix.