The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 06, 2001
Filed:
Jun. 24, 1998
Martine Hourcade, Paris, FR;
Patrice Lefrancois, Cormeilles en Parisis, FR;
Xavier Longaygue, Noisy le Grand, FR;
Institute Francais du Petrole, Rueil Malmaison Cedex, FR;
Abstract
The present invention relates to a method for predicting and controlling the hydrogen corrosion and embrittlement behavior of steels in the presence of H,S. In the method, at least the following stages are carried out: determining a characteristic value l,which is a function of the proportion of dislocations present in the lattice of a first steel sample treated under hardening conditions such that, after the hardening treatment, by quenching and tempering or by work hardening, the hardness of said steel reaches a maximum value at a threshold stress &sgr;,such that &sgr;,equals k·R,k being less than or equal to Rp,of said steel; determining a characteristic value l,which is a function of the proportion of dislocations present in the lattice of a second treated steel sample; and comparing l,and l,, and if l,is less than or equal to l,, the treated steel of the second sample is said to be non sensitive to hydrogen corrosion and embrittlement in the presence of H,S according to the criterion defined by the value of k. When the resultant steel has a value l,less than l,, the resultant steel can be used for the armouring of wires, for example.