CrB fine powder was added to austenitic stainless steel (SUS304L) powder compacts in order to enhance the ability of sintering by liquid phase formed through a eutectic reaction. The effects of CrB addition on the mechanical properties of sintered compacts were investigated.
Tensile properties are improved by liquid phase sintering because of densification, disappearance of small pores finely dispersed in the matrix and rounding of pores. Over 0.5 wt% CrB addition, however, produces the networks of liquid solidified microstructure which affect negatively the improvement of ductility.
Impact resistance is also improved by CrB addition. The fracture occurs by the mechanism of pore enlargement and coalescence in low density specimens, while in high density specimens, that occurs along the liquid solidified microstructure. The impact value of high density specimens below room temperature decreases with falling temperature, owing to the embrittlement of liquid solidified microstructure.