A hard corrosion resistant surface is provided on a ferrous substrate by first overlay welding onto the substrate surface a chromium containing ferrous material. The deposited overlay can then be machined. It is thereafter subjected to a carburization treatment at a temperature and for a time sufficient to cause the overlay to become converted to an austenitic material containing iron chromium carbides. After cooling, the carburized overlay material is heated for a time and at a temperature sufficient to cause the austenitic matrix material to precipitate secondary carbides and convert to a martensite matrix material upon cooling. It is also contemplated to initiate the aforesaid treatment with a suitably selected chromium containing ferrous material that thereby is not overlay welded.
The surface hardening diffusion process for an austenitic material such as 300-series stainless steel uses a pack carburization process at a temperature range from about 1500.degree. F. to about 2500.degree. F. for a period of time ranging from about one (1) to about eight (8) hours. Chromium carbides are formed on the surface of the austenitic material for increasing its wear resistance.
The present invention relates to a two-cycle internal combustion gasoline engine cylinder. The two-cycle engine cylinder according to this invention is characterized in that a smooth hard chromium plated layer is formed on a combustion chamber top inner surface of the cylinder.
A low alloy steel for use in building up industrial components subjected to service conditions requiring good impact toughness, resistance to tempering, and resistance to temper embrittlement, for example, for use as a build up layer for steel mill caster rolls and a submerged arc welding wire for deposition thereof. The composition of low alloy steel has less than about 0.1% C by weight, between about 1.5% and about 5.0% Ni by weight, and between about 0.5% and about 3.0% Mo by weight. Vanadium, Cr, and other carbide-formers are excluded from the low alloy steel sufficiently to avoid any significant precipitation of carbides upon deposition of the low alloy steel by welding onto an industrial component.
An overlayer for a use on industrial components such as steel mill caster rolls which require enhanced abrasion, corrosion, and gall resistance. The overlayer has relatively lower carbon levels and relatively higher molybdenum levels relative to other alloys used as overlayers, The overlayer has reduced susceptibility to sensitization and enhanced corrosion resistance.
A carburizing process for increasing the hardness of a case region of a steel component. In one form the application includes plating the outer surface of a stainless steel component with nickel prior to carburizing. One component includes a stainless steel object having a hardened case substantially free of continuous phase grain boundary carbides.
