Process, microstructure and microhardness of GH3039 superalloy processed by laser metal wire deposition

Abstract

Laser metal deposition has high build rate and it is suitable for fabricating parts with larger sizes. Using the metal wire as feedstock material in laser metal deposition is a potential and promising approach compared with other metal additive manufacturing technologies, due to the metal wire is with lower cost, higher material efficiency and less pollution to environment. However, the experience and development activities relevant to metal wire based additive manufacturing are relatively limited. In this work, laser metal wire deposition was conducted to fabricate single-track cladding layers of GH3039 superalloy at different processing parameters, the empirical models and correlations between the main processing parameters (laser power (P), laser scanning speed (V) and wire feeding rate (F)) and geometrical characteristics (clad width (W), clad height (H), penetration depth (h), dilution (D) and wetting angle (θ)) of the cladding layers were studied by employing the combined parameter PαVβFγ and regression analysis (RA) method, which provides the possibility of predicting the geometrical characteristics under the applied processing parameters. To verify the correctness of the empirical models and study the layer-by-layer problems, the multi-layer single-track thin wall of GH3039 superalloy was fabricated and investigated. Furthermore, the microstructure and the microhardness of the cladding layers which may be aid for facilitating the industrial applications of laser metal wire deposition were also studied.