摘要
This study analyzes the evolution of carbides in the tempering process of a newly developed semi-high speed steel cold forged roll with nitrogen addition using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray (EDX). The precipitation sequence of the carbides was identified in the entire tempering process and it can be expressed as M3C→M3C + M (C, N)Ⅱ→M( C, N)Ⅱ → M7C3Ⅱ + M23 C6. The secondary hardening in the tempering process was mainly due to the dispersed precipitation of fine M( C, N)n particles. The dissolution of M3 C tempered at high temperatures induced the precipitation and coarsening of M7 C31/ and M23 C6.
This study analyzes the evolution of carbides in the tempering process of a newly developed semi-high speed steel cold forged roll with nitrogen addition using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray (EDX). The precipitation sequence of the carbides was identified in the entire tempering process and it can be expressed as M3C→M3C + M (C, N)Ⅱ→M( C, N)Ⅱ → M7C3Ⅱ + M23 C6. The secondary hardening in the tempering process was mainly due to the dispersed precipitation of fine M( C, N)n particles. The dissolution of M3 C tempered at high temperatures induced the precipitation and coarsening of M7 C31/ and M23 C6.
基金
supported by the Baosteel Group Corporation Project (R05DSES220)