TECHNOLOGIES
Increasing the cutting machinability of 18ChGT steel due to increased sulfide content
When machining steel gear blanks for a long time, problems are observed during their turning and machining. Attempts to improve machinability using various heat treatment methods have not been successful. In this regard, the possibility of the influence of changes in the chemical composition of steel on its machinability was analyzed. The goal was set for the machinability of serial steel 18ChGT to be similar to the machinability of automatic steel, without reducing its mechanical properties. The improvement in machinability by cutting automatic steels is due to the presence of inclusions in its structure, which increase the fragility of the chips. These can be chemical compounds of metals (sulfides, phosphides, selenides, etc.), or inclusions of low-strength metals, for example, lead. The analysis of metallurgical processes for steel production led to the conclusion that the use of sulfides is economically feasible. When processing gears made of steel with a high sulfide content, the average resistance of the WNMG080408 pass plate was 214 pieces on the edge, and when processed from serial steel 18ChGT, the average resistance is 180 pcs on the edge, no changes were recorded for the rest of the properties. Also, when processing 18KChGT steel with a high sulfur content, chip formation was improved, and a reduction in lost working time was observed due to a fourfold reduction in the need to replace reusable containers for chips.