摘要
对铸造镍基高温合金K417G进行了不同冷却速率的凝固试验,并对凝固后的试样进行了光学金相和定量金相分析,研究了凝固冷速对合金显微组织的影响,通过线性回归的方法确定了平均枝晶间距与凝固冷速的关系。结果表明:凝固冷速增大明显细化树枝晶、MC碳化物和(γ+γ′)共晶。冷速对MC碳化物的量影响不大,但对(γ+γ′)共晶量有明显影响,过快和过慢的冷速都能引起(γ+γ′)共晶量增加。K417G合金的平均枝晶间距(λ/μm)与凝固时冷速(V/℃.s-1)存在λ=85.1V-0.35的对应关系,根据该关系式可以通过测量铸件不同部位的平均枝晶大小确定该部位凝固时的冷却速率。
The solidification tests were carried out with different cooling rate on cast Ni-base superalloy K417G.The effects of cooling rate on microstructure were investigated by analyzing solidified specimens using optical and quantitative metallography.The relationship between cooling rate and average dendritic spacing was determined by the method of linear regression.The results indicate that higher cooling rates are prone to form finer dendrites,MC carbides and(γ+γ′) eutectic.Cooling rate has little effect on th...
出处
《航空材料学报》
EI
CAS
CSCD
2006年第3期7-11,共5页
Journal of Aeronautical Materials
