Etude du dosage de l'hydrogene piege dans les aciers
The presence of hydrogen in steel can lead to embrittling and splitting, and can sometimes have dramatic consequences. This element easily penetrates the metal at various stages of production, during working off, for example, or soldering processes. Measures, which include casting in a vacuum or heating of soldering electrodes, are therefore taken to avoid its presence. These measures, however, often prove to be insufficient. Hydrogen interacts with steel in different ways, activating defects that act as hydrogen traps such as precipitates, inclusions and other imperfections. Although this interaction is not fully understood the work carried out by G. M. PRESSOUYRE at the Creusot laboratory has helped to further this understanding. Discovering the quantity of trapped hydrogen at a defect site allows the initiation of a split to be predicted. By studying the phenomenon of trap formation it is possible to distinguish the role of the different reversible or irreversible traps and calculate the critical concentrations of hydrogen that lead to splitting. In turn, by knowing the critical concentration of hydrogen in steel it is possible, in principal, to gauge whether splitting will take place by measuring the amount of hydrogen present. The phenomenon of splitting, however, requires local concentrations of hydrogen to be examined and not the total concentration, which is that which is determined by usual methods.
Bibliographic Reference: EUR 18801 FR (1999) 55pp.
Availability: Available from OOPEC Sales agents
ISBN: ISBN 92-828-5410-8
Record Number: 199911267 / Last updated on: 1999-08-27
Original language: fr
Available languages: fr