Influência do pré-aquecimento na perda de massa de revestimentos duros aplicados pelo processo de soldagem com arame tubular

Abstract

Hardfacing applications are largely used on parts that suffer from abrasions wear. Those materials have a high wear resistance characteristic that guarantee lower reposition and maintenance costs. They also assure a longer service life due to their great abrasion resistance. Materials such as high-chrome (FeCrC) content are showing great efficiency on those applications. One characteristic of those Hardfacing alloys is that usually they need a heat treatment, such as a preheating is required. The main objective of preheating is to reduce the cooling rate and reduce the thermal contractions caused by the rapid cooling. Moreover lower contraction stress is promoted and the formation of cracks is avoided. In this research high-chrome hardfacing alloys were deposited on an ABNT 1045 Steel by the fluxed core arc welding process. First, the hardfacing alloys were deposited without a preheating, then they were deposited with a preheat temperature of 350° C and with 450°C. Analysis of the welding surface such as the qualification and quantification of cracks and porosity, surface hardness and mass loss on the rubber wheel abrasion test were performed. At last the results will be collect and analyzed so that the preheating effect on the Hardfacing deposits can be related to the hardness, porosity and cracks and mass loss. The results from this research were also compared with the literature and other scientific article.