Ningbo Ningshing Precision Machinery Group Co., Ltd.Who We AreNo.25 Hongxiang Rd A area Industry, Hongtang Jiangbei, Ningbo, 315033, Zhejiang Province, ChinaFormerly known as Ningbo Ningshing Special-Steel Group Co., Ltd., we are a holding subsidiary of Ningbo Ningshing Holdings Corporation.
After years of development, we have successfully realized the transformation of "industry supply chain ecosystem" from only trading to integrated operation, including distribution and retail, precision processing, intelligent manufacturing, vacuum heat treatment, technical services and international trade, etc.
As one of the largest special steel distribution enterprises in China with imported and homemade tool steel materials, Ningshing P
Process: The heat treatment process of heating the ingot, casting or forging stock to a temperature slightly lower than the solidus for a long time, and then cooling slowly to eliminate the non-uniformity of chemical composition.
Objective: To eliminate dendrite segregation and regional segregation during solidification of ingot and homogenize the composition and structure.
The heating temperature of diffusion annealing is very high, usually 100~200 ℃ above AC3 or ACCM. The specific temperature depends on the degree of segregation and steel grade,
The heat preservation time is generally 10~15 hours. After diffusion annealing, complete annealing and normalizing are required to refine the structure.
It is applied to some high-quality alloy steel and alloy steel castings and ingots with serious segregation.
