Thermodynamic modeling of Cr-Al-C and Ni-Al-C systems for low-density steels  

作　　者：Wei-sen Zheng Yan-lin He Xiao-gang Lu 

机构地区：[1]State Key Laboratory of Advanced Special Steel,Shanghai University,Shanghai 200444,China [2]School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China

出　　处：《Journal of Iron and Steel Research International》2020年第10期1190-1199,共10页

基　　金：Thanks are given to the support from the NationalKey R&D Program of China(Grant No.2017YFB0304402);W.S.Zheng acknowledges the support from the Shanghai Sailing Program(Grant No.19YF1415700);the National Natural Science Foundation of China(Grant No.51901124).

摘　　要：The so-called low-density steels have generated a lot of interests with their high specific strength and ductility due to the addi-tion of the light element Al.ln order to accelerate the low-density steel design,a thermodynamic database has been developedwithin the present author group.Two Al-containing systems,i.e.,Cr-Al-Cand Ni-Al-C,were modeled and optimirzed with CALPHAD approach based on the reliable binary descriptions.For Cr-Al-C,system,the Gibbs energy of Cr2AlC phasewas described by a temperature-dependent polynomial with the aid of the experimental data on the heat capacity,instead of estimating heat capacity from Ncumann-Kopp rule.The incongruent melting temperature of Cr2AlC is 1762 K with theinvariant reaction of liquid+Cr3C2+Al4C3→Cr2AlC.The phase equilibria between Cr2AlC and binary phases were wellreproduced by using the present model parameters.For Ni-Al-C system,the liquid,fec and bec phases have been optimizedto fit the carbon solubility in these three phases.A good agreement between the calculated and experimental data has beenobtained using the present description of Ni-Al-C system.The reliable descriptions of the two ternary systems developedin the present work can be implemented into the thermodynamic database for low-density steels.

关 键 词：Cr-Al-C system Ni-Al-C system Thermodynamic model CALPHAD Low-density steel 

分 类 号：TG142.1[一般工业技术—材料科学与工程]