Tailoring the deformation mechanisms in a Ni-Co-based superalloy by controlling γ′ precipitate size

•The deformation mechanism exhibits a close correlation with the size of γ′ precipitates under low stain.•Microtwinning becomes the predominant deformation mode for the studied superalloy when compressed to 20%.•The optimizing of γ′ precipitate size can significantly enhance the formation of micro-twins in Ni-Co-based superalloys. The role of micro-twins in the high-temperature deformation of superalloys is crucial and influenced by precipitates and deformation conditions. This study investigates the deformation mechanisms in a Ni-Co-based superalloy with γ′ precipitates varying from 31 to 122 nm under two compression conditions at 760 °C. The deformation mechanism exhibits a close correlation with the size of γ′ precipitates under 5 % stain, while the formation of micro-twins is relatively limited. Microtwinning becomes the predominant deformation mode when compressed to 20 %. The micro-twins reach the peak intensity for the alloy with 47 nm-sized γ′ precipitate. The optimizing of γ′ precipitate size can significantly enhance the formation of micro-twins in Ni-Co-based superalloys. This strategy of modulating the deformation mechanism through precipitate size regulation offers valuable insights for the design of advanced alloys.