覆膜砂中碳纤维对真空差压铸造ZL205A合金组织的影响

Effects of Carbon Fiber Content of the SLS Mold on Microstructure of Vacuum Counter-pressure Casting ZL205A Alloy

通过测试与分析SLS砂型中不同碳纤维含量下真空差压铸造ZL205A合金的晶粒大小,研究了SLS砂型中不同碳纤维含量对真空差压铸造ZL205A合金微观组织的影响。结果表明,在覆膜砂铸型中加入碳纤维对铝合金试样的微观组织影响显著。ZL205A合金的晶粒大小随碳纤维含量的增加而显著减小,当碳纤维含量超过3%时,ZL205A合金晶粒随碳纤维含量增加而逐渐增大;当SLS砂型中碳纤维含量相同时,晶粒大小随试样壁厚的增加而增大。建立了真空差压铸造ZL205A合金晶粒大小与SLS砂型中碳纤维含量和试样壁厚的关系,当试样壁厚大于9mm时,试样壁厚对晶粒大小影响较大;当试样壁厚小于9mm时,碳纤维含量对晶粒大小影响较大。

Effect of carbon fiber content of the SLS mold on grain size of ZL205A alloy produced by vacuum counter-pressure casting were investigated through testing and analyzing the grain size subjected to different carbon fiber content. The results indicate that the grain size in aluminum alloy is refined greatly with the increase of carbon fiber content, however, the carbon fiber content is more than 3 %, the grain size is increased with the increase of carbon fiber content. At the same carbon fiber content, the grain size is increased with the increase of the sample thickness. Meanwhile, the relationship of the grain size of vacuum counter-pressure casting ZL205A aluminum alloy with carbon fiber content and sample thick- ness was established. When the sample thickness is more than 9 mm, effects of sample thickness on grain size is obvious, however, the sample thickness is less than 9 mm, effect of carbon fiber content on grain size is the major.