The impact of welding technology on the manufacture of metal baskets

Abstract

The submitted paper is closely connected with the challenging complex of problems relating to degradation of the anti-corrosion parts. The given anti-corrosion parts are represented by welded Cr-Ni steel baskets, which are also known as “hardening baskets”. The given “hardening baskets” are commonly used for embedding of the bearing parts to be quenched and tempered. Based on the utilisation, the mentioned welded metal baskets, which are made of X8CrNi25-21 steel, are exposed to the long-term cyclic thermal loading in the furnace. Relating to the manufacture of “hardening baskets” and investigation, the significant attention was paid to the effect of the used welding electrodes on the performance and quality of the welded joints. The weldability of austenitic X8CrNi25-21 steel has the considerable effect on these three phenomena: susceptibility of this material to the crack initiation, precipitation of chromium carbides in microstructure and occurrence of the intermetallic phases. The main objective was to evaluate the structure of welded joints produced by welding technology and the main features of their damage in order to compare the impact of individual filling materials on the quality of welds in the cage baskets as well as to evaluate the hardness course. In addition, evaluation of the macrostructure as well as microstructure changes was based on static tests. The results of evaluation are reflected in the recommendation of the most appropriate welding filling material. All aspects, which could lead to the occurrence of the critical states, were subjected to the complex investigation in the terms of the structural properties and moreover, there is also the final recommendation for possible elimination of the undesired phenomena.