Abstract：In the research, water cooled copper crucible-vacuum induction furnace was used to remelt and prepare specimen. The microstructure and high temperature compression mechanical properties of K418 superalloy and K418 alloy with 10%, 30%, 50% and 100% returned alloy proportion were studied by MEF3 Optical Microscope(OM), Quanta FEG 450 Scanning Electron Microscope(SEM), Energy Disperse X-ray Spectroscopy(EDS) and Gleeble 3500 Thermal-Mechanical Simulator. The results indicate that 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 σ0.2, Compression stress σb, Plastic strain εp and Total strain εt of various returns proportion alloy wave in a small range.
2018, Vol. 25 
