DIFFUSIVITY AND SOLUBILITY OF HYDROGEN AS A FUNCTION OF COMPOSITION IN FE-NI ALLOYS
DIFFUSIVITY AND SOLUBILITY OF HYDROGEN AS A FUNCTION OF COMPOSITION IN FE-NI ALLOYS
复制标题
DOI：
10.1007/bf02662750
复制
发表时间：
1971-01-01
期刊：
影响因子：
--
通讯作者：
SUBRAMAN.PK
中科院分区：
文献类型：
--
作者：
BECK, W;BOCKRIS, JO;SUBRAMAN.PK
用电化学方法测定了氢在Fe-Ni系合金中的渗透率P、扩散系数D和溶解度c。导出了扩散激活热和溶解热，其值从纯铁的10 - 4cm/s降到合金中Ni含量为40wt%时的10 - 10 cm/s。此后，它略有上升，达到纯镍的水平，在纯铁和40wt%镍之间，它的变化约为103%，然后保持不变，直到纯镍。结果P在5wt% Ni时加倍，然后福尔斯下降103倍，直到40wt% Ni，之后略微上升到纯镍的水平。在0 ~ 40wt%Ni范围内，控制P值的主要因素是合金中α相摩尔分数的下降。这一假设给出了P-成分关系的合理定量计算。在40和100 wt %之间，晶相均为γ，主要影响是合金中的氢键合，注意到的小变化是可以合理计算的。在该区域中溶解度的可忽略的变化反映了合金从40到100wt%Ni的可忽略的变化特征。在T> 200°C时，Fe-Ni（5wt%）的氢渗透率大于钯的氢渗透率。腐蚀速率和氢渗透性（因此，对氢脆的敏感性）在约50wt% Ni处通过最小值。Fe-Ni合金的腐蚀速率与氢渗透速率之间存在显著的平行关系。提出了一种解释。
An electrochemical method has been used to determine the permeability,P, diffusion coefficient,D, and solubility,c, of hydrogen in alloys of the Fe-Ni system. The heats of activation for diffusion and the heats of solution have been derived.Dfalls from ≃10−4sq cm per sec for pure iron to ≃10−10sq cm per sec for 40 wt pct of Ni in the alloy. Thereafter it rises slightly to that for pure nickel,crises by about 103between pure iron and 40 wt pct Ni, then remains constant up to pure nickel. The resultantPdoubles at 5 wt pct Ni and then falls by 103times up to 40 wt pct Ni, afterwards rising slightly to that for pure nickel. Between 0 and 40 wt pct Ni the dominant factor in controlling the value ofPis the fall of the mole fraction of the α phase in the alloy. This hypothesis gives a reasonable quantitative calculation of theP-composition relation. Between 40 and 100 wt pct, the crystallographic phase is allγand the major effect is the bonding of hydrogen in the alloy, the small changes noted being reasonably calculable. The negligible change of solubility in this region reflects the negligible change indcharacter of the alloy from 40 to 100 wt pct Ni. The hydrogen permeability of Fe-Ni (5 wt pct) is greater than that of palladium atT> 200°C. The corrosion rate and hydrogen permeability (hence, susceptibility to hydrogen embrittlement) pass through a minimum at about 50 wt pct Ni. A remarkable parallelism exists between corrosion rate and hydrogen permeation in Fe-Ni alloys. An interpretation is suggested.