Thermodynamics of hydrogen absorption and desorption in TC21 alloy  

作　　者：Xiao-Li Wang Yong-Qing Zhao 

机构地区：[1]School of Material Science and Engineering,Xihua University,Chengdu 610039,China [2]Northwest Institute for Nonferrous Metal Research,Shaanxi 710016,China

出　　处：《Rare Metals》2020年第12期1413-1418,共6页稀有金属（英文版）

基　　金：the Key Program in Xihua University(No.Z1120117);Department of Education Research Fund in China,Sichuan Province(No.12201453);the Open Research Fund of Key Laboratory of Special Materials and Preparation Technology,Xihua University(No.S2jj2012-019)。

摘　　要：In this paper,it was addressed a hydrogen absorbing and desorbing thermodynamics inα+βtype TC21 titanium alloy with high strength and toughness based on thermodynamic experiments and calculation.The relationship between concentration(C),temperature(T),and pressure(P)of TC21 alloy is shown by P-C-T curves during hydrogen absorption and desorption process,which were measured by multistep hydrogenation/dehydrogenation methods from 625 to 750℃.The P-C-T isotherms at a given temperature were separated into three regions.The partial thermodynamic functions of hydrogen reaction were evaluated by a modified form of Sievert’s law and P-CoTrelation of different regions was expressed by the modified Sievert’s law.The results show that the enthalpy of hydrogen reaction in the first and third region relies on hydrogen content.According to Vant’s Hoff law,enthalpy and entropy of hydrogenation platform in TC21 alloys are-53.58 kJ·mol^(-1)and-127.41 J·K·mol^(-1),respectively.Compared with P-C-T curves of hydrogen absorption,that of hydrogen desorption exists hysteresis.

关 键 词：Thermodynamic functions ENTHALPY ENTROPY Hydrogen absorption/desorption 

分 类 号：TG146.23[一般工业技术—材料科学与工程]