Controllable Quenching Process Research Of Steel

The paper chooses 45 steel cylinder parts as the subject of research. The common laws of quenching process under different practical quenching conditions are studied by using cooling curve method. The main characteristics of the polymer quenchant NH-B are described, and the cooling mechanism is analyzed. Cooling curves of specimen are figured out according to different quenching processes.Hardened case depths for 45 steel parts quenched in NH-B solution of different concentration have been measured by "hardness curve method"; therefore it supplies the NH-B quenchant users with the theoretical basis. The controllable quenching theory and measure for water-base quenchant is developed. Some experiments are conducted by adjusting the concentration, temperature and agitation of NH-B quenchant to control the quenching quality. Microstructure and hardness distribution on cross-section of the quenched parts are investigated. And the effects of different conditions on quenching quality and hardness distribution are discussed. The only purpose is to control and predict the hardened case depth by adjusting quenching conditions.Based on the principle of heat transfer and phase transformation, the model of steel part has been built. The three dimensional non-linear finite element analysis of the transient temperature field during quenching of 45 steel parts is simulated by using of ANSYS software.At last, the system design of quenching facilities is discussed and some rough improvement suggestions and new design ideas are brought forward.