Forging as a way to improve the quality and turning of specialty steels

The paper uses the examples of 07Kh16N6-Sh, 12Kh18N10T-VD, as well as 30KhGSA and 50KhFA steels, analogs of the AISI 301, AISI 321, UNSG 41500 (USA) and 14331 (Czech Republic) steels to study the forging effect on the material structure and cutting of the resulting workpieces in comparison with turning a conventional hot-rolled rod. It shows that forging introduction is able to significantly improve surface quality of the turned workpieces and reduce the tool loading. The result is achieved by obtaining a more uniform structure of the forging material relative to the original rods, as well as by smaller spread of the material hardness over the workpiece cross-section. The paper provides recommended forging modes and heat treatment of workpieces before turning. It identifies relationships between the workpiece material metallographic structure, its hardness and characteristics in the turning.
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