Effects of powder size and sintering temperature on microstructure and properties of porous K418 superalloys

The porous superalloy materials were prepared by loose packing sintering using the atomized K418 nickel-based superalloy spherical powders as the raw materials. The microstructure, permeability, capillarity, and compressive strength of the sintered porous material samples were analyzed, and the effects of sintering temperature and original powder particle size on the microstructure and properties of the porous K418 superalloys were investigated. The results show that, the average pore size and porosity decrease with the increase of sintering temperature. At the same sintering temperature, the average pore size and porosity of the sintered samples increase with the increase of the original powder particle size. At the sintering temperature of 1230 ℃ and the powder particle size of 53~150 μm, the comprehensive performance of the porous material samples is the best, the permeability is 13.69×10⁻¹⁵ m², the capillary pressure is 22.1 kPa, and compressive strength is 86 MPa.