Effect of tungsten on carbide formation in steel 30KhG

ConclusionsAlloying of Cr-Mn steel with tungsten inhibits diffusion processes, due to which the temperature at which elements are redistributed between the matrix and iron carbide increases. Alloyed chromium carbide is formed in the steel with ∼0.75% W in the process of tempering at 600°C. In the steel with 1% W chromium carbide is formed at 575°C. Hexagonal chromium carbide is formed in these steels due to gradual rebuilding of orthogonal iron carbide. Raising the tungsten content to 1.25% causes substantial enrichment of cementite with tungsten, and at 600°C hexagonal carbide (W, Cr)2C is formed by the aging mechanism, the tungsten content increasing considerably, and the concentrations of chromium, iron, and manganese decreasing, with increasing temperatures. A larger tungsten content leads to formation of carbide identified as tungsten carbide W2C.