Abstract: A process in which a steel is dipped in an aluminum-based bath wherein the composition and mean temperature of the bath and the immersion temperature of the steel are adjusted to obtain, in the immersion zone of the steel, a local bath temperature and composition resulting in an equilibrium with the solid phase designated as &thgr;≡FeAl3. Dipping is performed at a temperature higher than the temperatures normally employed in the art and a coating is obtained having at the interface with the steel an alloy layer significantly smaller in thickness than the art. The coating obtained better resists cracking and corrosion.

Abstract: The invention relates to an exhaust muffler for a motor vehicle, consisting of an external casing (1), an internal casing (2) and a central part (3) consisting of perforated tubing (4) and transverse partitions (5) assembled together to form a chicane, called the insides. The central part (3) is made of an enameled steel, the steel having the following composition in thousandths of a percent by weight:carbon between 0 and 100manganese between 0 and 500phosphorus between 0 and 30sulfur between 0 and 40aluminum between 0 and 60titanium between 0 and 200copper between 0 and 60nitrogen between 0 and 15,the remainder being iron and residual impurities, said steel being obtained by hot rolling at a final rolling temperature exceeding the Ar.sub.3 point to obtain a strip, which is coiled at a temperature higher than 600 degrees Celsius and, after cold rolling, is subjected to a recrystallization annealing.

Abstract: A method of treating a metal layer present as a coating on a sheet metal substrate, wherein a powder is applied to said metal coating by propulsive means (e.g., spraying or the like) when said coating is at least partially in the liquid state. The powder is prepared by atomization in a manner adapted such that the powder is in the form of agglomerates having a mean diameter which is greater than the thickness of said liquid-state metal coating. With this use of this powder, it is easier to treat metal coatings in the liquid state, and the resulting treated coating is highly homogeneous, even if the atomized powder has a plurality of types of components.