Hydrogen absorption during zinc plating on steel
1997; Elsevier BV; Volume: 39; Issue: 3 Linguagem: Inglês
10.1016/s0010-938x(97)86101-x
ISSN1879-0496
AutoresT. Casanova, Fernando Soto, Marielle Eyraud, J. Crousier,
Tópico(s)Welding Techniques and Residual Stresses
ResumoVoltammetry, galvanostatic polarisation and permeation experiments were used to determine the origin of the hydrogen absorbed in a steel substrate during zinc plating. Two hypotheses could be proposed to explain the hydrogen embrittlement of steel. The first hypothesis was the absorption of hydrogen by the bare steel before formation of the first zinc crystallites. The second hypothesis was the trapping of hydrogen in the deposit during plating and subsequent diffusion of hydrogen in steel. The results show that hydrogen evolution on bare steel was retarded by a zinc Under Potential Deposition. During zinc plating, the hydrogen permeation current decreased progressively with thickening of the deposit, showing a slight barrier effect. After 24 min the permeation current was still 80% of the maximum, and it continued decreasing for 100 min. It is concluded that the barrier effect does not prevent hydrogen trapped in the deposit to diffuse through the steel substrate.
Referência(s)