Characterization of borided Inconel 625 alloy with different boron chemicals

In this study, inconel 625 ni-based superalloy, widely used in industrial application, was borided with three different boriding powders. the boriding powders used were as follows: the first one consists of 90% elemental nanoboron and 10% nabf4, (nb), the second one consisting of 90% nano hexagonal boron nitride and 10% nabf4 (h-nbn), and the third one being commercial ekabor 2 powder. boriding is conducted at 1000 °c for 180 minutes. then the borided samples were investigated with optical microscopy, microhardness test and x-ray diffraction (xrd) analysis. in these investigations, the effect of boriding powders with different chemical content on the properties of the coating layer and the phase formation was examined. as a result of these examinations it was observed that boride, silicide and nitride coating layers were obtained depending on the chemical content of boriding powder. the fact that the boron phases with higher boron contents were obtained with nano boron powder indicate that the degree of purity of boron powder has an effect on the type of phases to be formed. in this study, undesirable silicide layer formation encountered in ni-based super alloys was prevented by changing the chemical composition of boriding powders. furthermore, nano boron and hexagonal boron nitride powders, have been developed as alternative boron powders to commercial ekabor-ni boriding powder as well as thicker coating layers have been obtained by using these newly developed boriding powders than commercial boron powders (ekabor 2, ekabor-ni and b4c).