自蔓延熔铸法制备CuCr合金及表征

采用自蔓延熔铸法制备出CuCr合金.分别考察了反应物配比对合金成分、添加剂CaF2对合金试样宏观形态、不同铸模对合金试样微观结构以及铸模预热温度对合金试样的影响.实验结果表明:反应物的理想配比为w(CuO):w(Cr2O3):w(Al)=100∶140∶160;添加剂CaF2降低了渣的熔点并强化了渣金分离效果;金属铸模中合金冷却速度比较大,所得合金试样的结晶晶粒较细;采用石墨铸模浇注时,提高铸模的预热温度可改善合金的质量,当预热温度为500℃时,可以得到致密的CuCr合金.

Preparation of CuCr Alloy by SHS Melting and Its Characterization

CuCr alloy was prepared by self-propagating high-temperature synthesis (SHS) melting. How the proportioning of reactants, additive CaF2, different molds and mold preheating temperature affect the alloy composition, macromorphology and microstructure of the alloy specimens were investigated respectively. Experimental results indicated that the reasonable proportioning of the reactants is 100:140:160 of ω(CuO):ω(Cr2O3):ω(Al); the additive CaF2 can not only lower the melting point of slag but also can improve the efficiency of separating metal from slag; the high cooling rate of the alloy in metal mold makes its crystal grains finer; and when casting in the graphite mold, the quality of the alloy can be improved if the preheating temperature is rising, e.g. the compact CuCr alloy is available at a preheating temperature of 500°C.