Estudo dos efeitos dos parâmetros de soldagem MIG em revestimentos a base de níquel depositados em aço API 5L X70.

Abstract

The application of nickel alloy coatings is commonly performed in the oil and gas industry to increase the life of equipment in aggressive environments, given that this procedure improves corrosion resistance without a significant increase in production cost when compared to mas-sive equipment manufactured with other alloys. The present work evaluates the best process conditions in the deposition of coatings to nickel alloy bases applied by the MIG welding pro-cess in API 5L X70 steels. As base metal plates of the API 5L X70 steel were used as the ad-dition metal, the Ni-based alloy Inconel 625 as the solid ring. As an optimization tool, a com-plete experimental design 2³ was used, associated with the technique of surface response me-thodology (MSR). Measurements of the geometric characteristics (width, reinforcement, convexity index, penetration and dilution) were made, besides raising the microhardness profile of the deposited coatings that used higher and lower welding e-nergy. The most satisfactory results were coatings having 5.8% dilution, 6.19 mm reinforce-ment and 22 mm wide. The microhardness values were influenced directly by the increase of the welding energy used.