Effect of N-bonding elements on dissolution and precipitation of B in micro B-treated ultra-heavy plate steels has been investigated,utilizing Thermo-Calc thermo-dynamic software and experimental test.The calculation ...Effect of N-bonding elements on dissolution and precipitation of B in micro B-treated ultra-heavy plate steels has been investigated,utilizing Thermo-Calc thermo-dynamic software and experimental test.The calculation results show that Titanium or excessive Aluminum content is effective to bond Nitrogen,preventing BN from forming and thus keeping boron in solid solution in austenite,while Vanadium is not.The experiment has also revealed that slight amount of solution Boron by addition of Ti or a little excessive Aluminum is helpful to improve hardenability of the steels.展开更多
On the basis of a multi-length scale modeling, a mixture-averaged multi-component/multiphase micro- segregation model was proposed without pre-set function for the micro-scale solute profile. The model explains the ef...On the basis of a multi-length scale modeling, a mixture-averaged multi-component/multiphase micro- segregation model was proposed without pre-set function for the micro-scale solute profile. The model explains the effect of morphologies of solidifying phases and solid back diffusion （SBD） on segregation, and covers the two limiting solidification cases of Scheil and Lever-rule models. A commercial Thermo-Calc software package/database was linked to the algorithms via its TQ6-interface for instantaneous determination of the related thermodynamic data of the multi-component alloys. The influences of cooling rate and other parameters on the solidification path and micro-segregation behavior were numerically investigated by sample calculation of the ternary AI-Cu-Mg alloys. A parallel experimental investigation on AI-Cu-Si alloys solidified under different cooling conditions was conducted to validate the theoretical model. Reasonable agreements were gained between the predicted solidification paths and the measured results.展开更多
文摘Effect of N-bonding elements on dissolution and precipitation of B in micro B-treated ultra-heavy plate steels has been investigated,utilizing Thermo-Calc thermo-dynamic software and experimental test.The calculation results show that Titanium or excessive Aluminum content is effective to bond Nitrogen,preventing BN from forming and thus keeping boron in solid solution in austenite,while Vanadium is not.The experiment has also revealed that slight amount of solution Boron by addition of Ti or a little excessive Aluminum is helpful to improve hardenability of the steels.
基金supported by the Open Project of State Key Laboratory of Powder Metallurgy of Central South University (Grant No. 2008112042)the National Natural Science Foundation of China (Grant Nos. 51071062 and 50801019)Project 973 (Grant No. 2011CB610406)
文摘On the basis of a multi-length scale modeling, a mixture-averaged multi-component/multiphase micro- segregation model was proposed without pre-set function for the micro-scale solute profile. The model explains the effect of morphologies of solidifying phases and solid back diffusion （SBD） on segregation, and covers the two limiting solidification cases of Scheil and Lever-rule models. A commercial Thermo-Calc software package/database was linked to the algorithms via its TQ6-interface for instantaneous determination of the related thermodynamic data of the multi-component alloys. The influences of cooling rate and other parameters on the solidification path and micro-segregation behavior were numerically investigated by sample calculation of the ternary AI-Cu-Mg alloys. A parallel experimental investigation on AI-Cu-Si alloys solidified under different cooling conditions was conducted to validate the theoretical model. Reasonable agreements were gained between the predicted solidification paths and the measured results.
