涡轮叶片用K418B高温合金SLM工艺优化与性能研究OA

This study systematically investigates the optimization of selective laser melting(SLM)process parameters for K418B nickel-based superalloy to enhance its mechanical properties.The effects of key parameters,such as laser power and scanning speed,on the density,microstructure,and mechanical performance of the fabricated parts were explored.The optimal process window was determined by characterizing and quantifying micro-defects in samples prepared with various volumetric energy densities(Ev).Furthermore,the intrinsic relationship between process parameters,microstructure evolution,and mechanical properties was revealed through EBSD analysis and in-situ tensile testing.The results demonstrate that a relative higher density exceeding 99.6%can be consistently achieved when the Ev is below 60 J/mm³,effectively suppressing defects like pores and cracks.Within the optimal process window of Ev=40～50 J/mm³,the alloy exhibited excellent comprehensive mechanical properties,with its yield strength,ultimate tensile strength,and elongation reaching 780 MPa,875 MPa,and 2.5%,respectively.This work confirms that optimizing SLM process parameters to minimize micro-defects is crucial for improving the performance of the K418B alloy.