High chromium cast iron self protective build-up welding cored welding wire and its usage

Abstract

The self-protective high chromium cast iron cored build-up welding wire has metal powder core comprising nickel powder 6-8 wt%, middle carbon manganese iron 8-10 wt%, No. 45 ferrosilicon 9-12 wt%, high carbon ferrochromium 65-75 wt%, metal Cr powder 18-21 wt%, ferromolybdenum 5-7 wt% and Al-Mg powder 1.5-2.5 wt%, and with one welding wire filling amount of 0.49-0.53. The present invention makes it possible to use the welding wire in submerged arc welding without needing added flux and protecting gas, results in raised comprehensive welding performance and raised welding quality, and may be applied widely in build-up welding field requiring high antiwear, anticorrosive and anticracking performance.

Description

technical field [0001] The invention relates to a metal welding material, in particular to a high-chromium cast iron self-shielded surfacing flux-cored welding wire and a use method thereof. Background technique [0002] At present, most manufacturers at home and abroad use high-chromium cast iron materials for surfacing welding of internal mixers in rubber machinery, and use slag protection or gas protection for surfacing welding, because high-chromium cast iron materials have good wear resistance and have certain Corrosion resistance, only a few manufacturers have used other materials for surfacing, and different materials have been used for the difference in the post-surfacing processing of the rotor in the internal mixer and the semi-circular cylinder. However, surfacing welding with ordinary high-chromium cast iron materials requires gas protection or flux protection, which consumes gas and flux, and requires more equipment during welding, and the work is not very conve...

AI Technical Summary

Problems solved by technology

However, surfacing welding with common high-chromium cast iron materials requires gas protection or flux protection, which consumes gas and flux, and requires more equipment during welding, and the work is not very convenient. On the other hand, surfacing welding with high-chromium cast iron materials, Whether it is high hardness or low hardness (HRC40~50), cracks are easy to occur. Even if preheating and overlay welding are used, the cracks are still serious, and there is a phenomenon of falling blocks when the internal mixer is working. This is also recognized as a problem for experts at home and abroad. It is one of the most difficult problems to further improve the surfacing quality and service life of the internal mixer. Moreover, the requirements for the semi-circular cylinder and rotor surfacing of the internal mixer are also different. After the rotor is surfacing, it only needs to be polished, and the hardness of the surfacing layer is higher. Good, but the surfacing hardness of the semi-circular cylinder is not required to be too high, HRC40-50 is enough, but mechanical finishing is required