The effect of boron powder addition on wear properties of submerged hard facing welding

When worn and likely to worn surfaces are coated with hard facing, their service life increase. One of the maintance method for the worn surfaces is the application of Submerged hard facing welding. In this study, OP 1250 A welding powder, which is used commanly, with additions of Boron and Graphite are used. SG2 was used as welding wire. Samples were welded under N and in the air. Samples were cut out for hardness, and microstructural investigations. Hardness measurements and microstructural investigations were carried out on these samples. It is pointed out from the examinations that hardness of weld increased with the addition of Boron and Graphite and the usage of N. The highest hardness value was obtainted with the powder combination of 40 % Boron, 10 % Graphite and 50 % OP 1250 A under N. Key Words : Submerged arc welding, hard facing, boron, wear, tribology