Title: Thermomechanical annealing technology for martensite steel sections
Application Number: 87102389 Application Date: 1987.04.01
Publication Number: 1030097 Publication Date: 1989.01.04
Approval Pub. Date: Granted Pub. Date: 1990.01.03
International Classifi-cation: C21D1/26,C21D8/00
Applicant(s) Name: General Research Inst. of Iron and Steel, Ministry Address:
Inventor(s) Name: Luo Di
Attorney & Agent: CHENG GUANGHU
Abstract:
     This invention is characterized by annealing treatment in two steps. The first step utilizes residual heat after hot-work to hold the temperature at any level between phase transition temp. of martensite Ms and 680 deg.C, and the second step is to hold the temp. at any level between 700 deg.C and temp. Acl. The new procedure overcomes a series of disadvantages of the traditional technology caused by phase transition of martensite on cooling to room temp. after hot-work. It prevents the steel from production of cracks after hot-work, imparts proper hardness, improved construction and properties to the steel, raises quality and rate of finished products, and reduces power comsumption.
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