The differential etching methods of carbides M_6C, MC and M_(23)C_6 in die steel havebeen studies by volt-ampere method and potentioastatic method. It can be used for the observation ,identification and quantitative a...The differential etching methods of carbides M_6C, MC and M_(23)C_6 in die steel havebeen studies by volt-ampere method and potentioastatic method. It can be used for the observation ,identification and quantitative analysis of carbides.展开更多
On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1 , Ac3 , and Ms were measured by DIL805A quenching dilatometer....On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1 , Ac3 , and Ms were measured by DIL805A quenching dilatometer. The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis, and three corresponding equations were obtained. These equations, in which the interactions of the elements were considered, showed more effectiveness than the traditional ones. In addition, the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests. The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed; the equations obtained were verified by using several kinds of steels. The predicted values were in accordance with the results of the experiments.展开更多
文摘The differential etching methods of carbides M_6C, MC and M_(23)C_6 in die steel havebeen studies by volt-ampere method and potentioastatic method. It can be used for the observation ,identification and quantitative analysis of carbides.
基金Item Sponsored by Shanghai Leading Academic Discipline Project(T0101)Science and Technology Commission of Shanghai Municipality(065211028)
文摘On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1 , Ac3 , and Ms were measured by DIL805A quenching dilatometer. The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis, and three corresponding equations were obtained. These equations, in which the interactions of the elements were considered, showed more effectiveness than the traditional ones. In addition, the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests. The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed; the equations obtained were verified by using several kinds of steels. The predicted values were in accordance with the results of the experiments.