L'acier inoxydable Top-Gloss 904L est utilisé dans les montres haut de gamme

Les montres sont un outil utilisé dans la vie quotidienne pour indiquer l'heure. Comparées à d'autres dispositifs de mesure du temps, les montres se portent directement au poignet, ne prenant aucun espace. Ce sont également des objets décoratifs et, plus récemment, des symboles de statut.

L'acier inoxydable est le matériau le plus largement utilisé pour les montres. Les montres en acier inoxydable ont un éclat presque miroir et une sensation de solidité, fraîcheur au toucher, ce qui les rend populaires auprès du public.

Une montre magnifiquement conçue est considérée comme un bijou de haute qualité. Cependant, en tant que bijou porté au poignet, elle est souvent sujette à l'usure, provoquant souvent des rayures et des frottements. Les marquages autrefois délicats deviennent souvent rayés, perdant leur élégance originale.

Donc, les horlogers ont des exigences extrêmement strictes pour les marquages, demanding not only intricate and beautiful patterns but also durability and corrosion resistance.

D'abord, 904L is a super-austenitic stainless steel, meaning it is non-magnetic and cannot be hardened by quenching.

Rolex uses 904L steel, where the “L” stands for Lower Carbon, rather than the previously mentioned aluminum addition. Typiquement, le “L” alloy has a slightly lower hardness due to the lack of carbon, but this is negligible. Cependant, its corrosion resistance is excellent.

So, what is the hardness of this alloy?

904L 183HV

This is already a relatively soft steel. Even if 904L were Rolex’s own formula, the hardness wouldn’t change much.

Hard platinum jewelry, such as PT900/IR, can scratch both types of steel. Truly hard stainless steels, such as DSN9 or the stainless steel used in Swiss Army knives, have a hardness of 600HV.

As for corrosion resistance, 904L stainless steel is good, but not the best. Many high-molybdenum, high-vanadium, and DSN9 stainless steels are far superior. Cependant, it is sufficient for use in watches.

The 904L stainless steel supplied by Top Bright Metal is a super-austenitic stainless steel with a high chromium, nickel, and molybdenum content, offering excellent corrosion resistance. It offers excellent resistance to uniform corrosion, pitting and crevice corrosion, intergranular corrosion, stress corrosion cracking, and general corrosion, particularly in dilute sulfuric acid.

Because 904L has a very low carbon content (maximum 0.020%), it does not precipitate carbides during standard heat treatment and welding. This eliminates the risk of intergranular corrosion that can occur after standard heat treatment and welding. Due to its high chromium, nickel, and molybdenum content, as well as the addition of copper, 904L can be passivated even in reducing environments such as sulfuric and formic acids.