Nano-TiC Particle Reinforced GH3536 Composite Powder And Its Selective Laser Melting Formin

In this study,selective laser melting（SLM）was applied to create crack-free nickel-based composites using nano-TiC particle-reinforced GH3536 alloy.Mechanical alloying（MA）was utilized to create MA composite powders of nano-TiC particles reinforced GH3536 alloy,which was then used to create SLM TiCp/GH3536 composites.On the microstructure and properties of TiCp/GH3536 composites,the impact of volume energy density（VED）was investigated.Thermal plasma spheroidization（TPS）was used to create MA+TPS composite powders from the uneven MA composite powder that was abandoned during the SLM process.To test the viability of powder recycling,SLM TiCp/GH3536-2 composites made from the MA+TPS composite powders were employed.The results lead to the following conclusions:By using a ball milling machine at a speed of 200 rpm,a ball-to-powder ratio of 5:1,and a milling period of 5 hours,the composite powders were created.On the surface of the powders,the nano-TiC particles are dispersed uniformly.The composite powders have a sphericity of 0.965,an average particle size of 29.58μm,a fluidity of 18.6 s/50g,and an apparent density of 4.22 g/cm³.After TPS recovery,the MA+TPS composite powders have a sphericity of 0.965,an average particle size of 33.65μm,a fluidity of16.1 s/50g,and an apparent density of 4.184 g/cm³.On the surface of MA+TPS composite powders,there is a layer of core-shell submicron particles with an average particle size of 183.27 nm,and nano-TiC particles are equally dispersed inside the grains of the matrix alloy.As the plasma power increases,the particle size of the composite powder drops,and the number of submicron particles on the surface increases.The MA+TPS composite powders are enhanced when submicron particles were eliminated.This demonstrates how waste powder may be shaped using TPS treatment during the SLM process.The cubic texture（100）in various directions is present in the TiCp/GH3536composites created using MA composite powder.Following the addition of nano-TiC particles,the matrix GH3536 alloy’s increased recovery and recrystallization structure is mostly to blame for the reduction in dislocation density and the disappearance of microcracks.The primary strengthening phases in TiCp/GH3536 composites are M₂₃C₆carbide and the TiC ceramic phase.Both of these are non-coherent interfaces without reactants and have good interfaces with the GH3536 matrix.With an increase in VED,the TiCp/GH3536 composites’density,tensile strength,and yield strength first rise and subsequently fall.The composite can have a density of 99.96%.The tensile and yield strengths that are the greatest are 1137.2 MPa and 900.6 MPa,respectively.In the temperature range of 0 to 500℃,the elongation,thermal diffusivity,and thermal expansion coefficient rise linearly.The instantaneous thermal expansion coefficient and thermal diffusivity both rise with the increase in VED at the same temperature.SLM was used to create TiCp/GH3536-2 composites from the MA+TPS composite powders that have undergone TPS treatment.Although there is anisotropy in the microstructure and characteristics,there are no microcracks or nano-TiC particle clusters inside.A well-bonded incoherent interface is formed by the M₂₃C₆ carbide,TiC ceramic phase,and GH3536 matrix.M₂₃C₆ carbide has numerous twins and stacking defects along the（111）plane.Similar to TiCp/GH3536 composite,TiCp/GH3536-2 composite has a yield strength of 799.8 MPa and a tensile strength of 1022.5 MPa.This demonstrates that using the MA+TPS composite powders treated by TPS for the SLM molding technique can result in significant cost savings.