Análise de falha em rolete recravador sujeito a solicitações simultâneas de corrosão e desgaste.

Abstract

The use of martensitic stainless steel AISI 440C, has increased significantly in the food industry due to their properties of resistance to corrosion and wear, especially after being heat treated. In order to obtain lower cost, the canned food industry has sought alternative materials to manufacture the rollers of recravadoras cans, replacing the original material of the rollers, manufactured with TiN coating, by the hardened and tempered martensitic AISI 440C steel. However, it is observed that the lifespan of rollers made of AISI 440C has been very low, this fact, instead of reducing costs, has increased maintenance interventions causing an increase in production costs. This paper aims to conduct a failure analysis and investigate the mechanisms active in the process of accelerated degradation in rollers made of martensitic stainless steel AISI 440C, employed in a food industry. Samples'roller were obtained and characterized by metallographic analysis and hardness and microhardness measurements. The results show the occurrence of intergranular corrosion in the samples, possibly attributed to inadequate heat treatment, and that may be contributing to the reduction of the lifespan of the rollers due to the existence of simultaneous request for sliding wear, mechanism known tribocorrosion. In this work were also prepared in stainless steel AISI 440C samples that were subjected to heat treatment to improve the dissolution of chromium carbides, for, from the best result of dissolution submit material heat treated with the best chrome condition solubilized trials of tribocorrosion and potentiodynamic polarization.