水冷铜坩埚重熔吸铸高温合金K418的成分、组织和力学性能

The composition,microstructure and mechanical properties of superalloy K418 by remelting suction casting

采用水冷铜坩埚-真空感应加热炉设备,对含有返回料比例为0%、10%、30%、50%和100%的K418高温合金进行重熔和吸铸制样。研究了含不同返回料比例的K418合金的成分、组织和高温压缩力学性能。研究结果表明,重熔对K418新料合金和含返回料合金的主要合金元素含量无显著影响。新料合金、含10%返回料合金、含30%返回料合金、含50%返回料合金的二次枝晶臂距相差不大。含返回料合金K418在晶界或二次枝晶臂上均存在点状、块状和条状的碳化物和氧化物。不同含量返回料合金在850℃时的屈服强度和抗压强度变化不大,塑性应变量、总应变量趋于平稳。

In the research,water cooled copper crucible-vacuum induction furnace was used to remelt and prepare specimen.The composition,microstructure and high temperature compression mechanical properties of superalloy K418 and K418 alloy with 10%,30%,50% and 100%returned alloy proportion were studied.The results indicate that the composition of K418 virgin alloy and returned alloy are not changed by remelting suction casting,and secondary dendrite arm spacing（SDAS）of K418 alloy with 0%,10%,30%,50% returned alloy proportion are almost same.The dot or bar carbide and oxide are found in grain boundary and SDAS of various returns proportion alloy.Inaddition,the yield stress,compression stress,plastic strain and total strain of various returns proportion alloy wave in a small range.