PREP法FGH95粉末的预热处理

研究了ＰＲＥＰ法制备的ＦＧＨ９５粉末经不同温度预热处理后的粉末颗粒表面与内部显微组织的变化。试验结果表明：采用预热处理方法既可使粉末颗粒显微组织更加均匀化，又可使粉末颗粒中的亚稳碳化物ＭＣ′发生分解和转变，重新析出更稳定的ＭＣ、Ｍ２３Ｃ６及Ｍ６Ｃ碳化物，明显改变碳化物的稳定性和分布状态。

Numerical analysis on solidification process and heat transfer of FGH95 superalloy droplets during PREP

In order to understand the relation between microstructure of superalloypowders and its solidification progress, the processing parameters are optimized during plasmarotating electrode processing (PREP). It was predicted from the results that the droplet velocities,droplet temperature, and fractional solidification with flight time about FGH95 superalloy droplethave been carried out based on Newtonian heat transfer formulation coupled with the classicalheterogeneous nucleation and the specific solidification process. It has been found that the dropletdynamic and thermal behavior is strongly affected by the distribution of droplet diameters, theproportion of cooling atmosphere, but is relatively unaffected by the droplet superheat.

等离子旋转电极雾化FGH95高温合金粉末的预热处理

在不同热处理制度下对等离子旋转电极雾化 (PREP)FGH95高温合金粉末颗粒进行预热处理 ,并对热处理粉末颗粒微观组织、碳化物析出相及γ′相的变化规律进行研究。结果表明 :随着预热处理温度升高 ,树枝晶组织逐渐消失 ,γ′相由圆形逐渐转变为方形 ,粉末颗粒中的MC′型亚稳碳化物发生分解和转变 ,析出稳定的MC ,M2 3C6及M6C型碳化物。M2 3 C6碳化物的析出温度为 95 0℃ ,M2 3 C6与M6C碳化物的相互转变温度为 10 0 0～ 10 5 0℃ ,M2 3 C6和M6C的溶解温度为 110 0℃。