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用过度冷却的方法改变钢的性能已不是新问题,早在三十年代国外就开始研究零下温度对钢的相变影响,确认淬火钢零下冷却导致残余奥氏体向马氏体转变;并提出高速钢冷处理工艺。由于试验结果的不统一及当时测试手段的局限,使该项研究停滞不前。冷处理工艺在工厂只在某些场合下才得到有限应用。到了七十年代由于低温技术的解决,测试手段的完善,人们又重新注视低温处理工艺,并由通常的-78℃冷处理扩展到-196℃冷处理——即所谓“深冷处理”(或“超低温处理”)。试验研究证实,零件经深冷处理使用寿命可提高几倍甚至十几倍。深冷处理的组织,不仅有残余奥氏体转变,亦有马氏体转变和碳化物微细化过程。
It is not a new problem to change the performance of steel by overcooling. As early as the 1930s, the influence of sub-zero temperature on the phase transformation of steel was studied. It was confirmed that the sub-zero cooling of quenched steel resulted in the transformation of retained austenite to martensite. High-speed steel cold treatment process. Due to the inconsistency of the test results and the limitations of the test methods at that time, the study was stagnant. Cold treatment is only limited in some cases at the factory. In the seventies, due to the improvement of cryogenic technology and testing methods, people have re-focused on the low-temperature process and extended from the normal cold -78 ℃ to the cold -196 ℃ - the so-called “cryogenic treatment” "). Experimental studies have confirmed that the service life of parts by cryogenic treatment can be increased several times or even ten times. Cryogenic treatment of the organization, not only retained austenite transformation, martensite transformation and carbide refining process.