A study of selected properties in high dispersion padding welds produced in machine elements

This paper presents selected laboratory research results concerning the production of high dispersion padding welds that were made from Castolin EnDOtec DO390N P pulverized nanowire on acid resistant 0Hl8N9 steel using laser technology. The analysis of the microstructure showed a high dispersion of the micro- and nano-structure where the phase particles of large volume carbide (MC), M23(BC) boron carbides, and M2B borides are distributed in the fine-grained iron matrix. The study found extensive differentiation of chemical composition in the micro-areas and extensive non-homogeneity of the microstructure due to repeated laser melting of the padding weld layer. Its surface hardness was 68-72 HRC and the cross-sectional microhardness was as high as 990 - ll00 HV0, l.