DD6单晶高温合金凝固特性研究

Isothermal Solidification Properties of DD6 Single Crystal Superalloy

利用等温凝固淬火法、光学金相技术、定量金相技术以及扫描电镜、能谱分析等方法,研究了Re含量为2%的DD6单晶高温合金的凝固特性,结果表明,合金凝固过程中所析出相依次为γ相→MC相→共晶γ′→枝晶间γ′→枝晶干γ′,DD6合金的固-液相温度范围(ΔT)、有效结晶温度范围(ΔT2)和F值(枝晶间失去补缩能力温度下的液相体积分数)较小,铸造性能较好。

Solidification properties of DD6 single crystal superalloy containing 2% rhenium were investigated by isothermal solidification quenching, optical microscope, metallographic quantification, SEM (scanning electron microscope) and EDS. The results reveal that phase in the alloy is precipitated in such sequence of γ phase to MC phase to eutectic γ′ phase to inter-dendritic γ′ phase to dendritic γ′ phase. The alloy exhibits desirable castability as a result of low T, T2 and F values.