Understanding Hydrogen Redistribution During Steel Casting,and Its Effective Extraction by Thermally Induced Up-Hill Diffusion

作     者：Gaude-fugarolas Daniel 

作者机构：Independent Research and Consultancy in Physical Metallurgy and Engineering c/.Alcalde Joan Batalla408340 Vilassar de MarSpain 

出 版 物：《Journal of Iron and Steel Research International》 (钢铁研究学报(英文版))

年 卷 期：2011年第18卷第S1期

页      面：159-163页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 080201[工学-机械制造及其自动化] 

主　　题：hydrogen diffusion embrittlement extraction 

摘      要：The severe loss of ductility caused by hydrogen in high strength steels has been the object of intense research during *** of the high mobility of hydrogen once has entered the metal,even in comparison with other interstitial atoms like carbon and nitrogen,a rigorous description of hydrogen fluxes during manufacturing of steel components is considered to be essential.A physical model of interstitial element diffusion is used to study the fluxes of hydrogen during solidification and cooling of cast *** particular,the present model contemplates diffusion in its most comprehensive description,i.e.,atom diffusion is driven by a reduction of the Gibbs energy of the ***,it is only considered the case in which diffusion occurs to reduce the concentration gradient of an element at constant matrix composition and ***,in a more general view,and as was proven by Darken (1949),diffusion may occur even up-hill the composition gradient as long it still leads to a reduction of Gibbs energy in the *** diffusion occurs due to a temperature gradient,it has been referred to as thermal diffusion or Ludwig-Soret *** model presented incorporates physical description of thermal agitation and atom mobility of interstitial elements,the influence of temperature gradients,solubility and saturation of the interstitial elements as function of temperature and matrix phases,as well as the kinetics of degassing at high *** application of this model shows how hydrogen localizes in some regions of the component to a degree that depends on manufacturing conditions and where it may reach concentrations well beyond the initial average concentration in the *** model describes as well how the FCC to BCC phase transformation may drive hydrogen concentration beyond supersaturation,due to the disparate capability of these phases to dissolve *** the other hand,this study has also enabled the development of a method for the