Disclosed is a method for surface treatment of a steel component, providing high resistance to wear and corrosion, including nitriding or nitrocarburising to form a compound layer with a thickness of at least 8 micrometers made up of iron nitrides having phases ε and/or γ′, oxidizing to generate a layer of oxides with a thickness of 0.1-3 micrometers, and soaking in an impregnation bath during at least 5 minutes at room temperature, the bath being made up of at least 70 wt %, ±1%, of a solvent made up of a mixture of hydrocarbons formed by a C9 to C17 alkane fraction, 10 to 30 wt %, ±1%, of at least one paraffin oil formed by a C16 to C32 alkane fraction, and at least one additive such as a synthetic phenolic additive with a concentration of 0.01 to 3 wt %, ±0.1%.

A method is provided for forming wear-resistant layer on the surface of cylinder bores a cylinder drum of a hydrostatic axial piston machine within which a respective piston is moved in a manner subject to intensive wear. The cylinder bores are gas nitrocarburized in two stages to minimize the wear and include a thin uniform connecting layer that has a thickness of 4 to 16 μm and a comparatively thick underlying diffusion layer.

An embodiment of the invention describes a method of treating an article to improve its corrosion resistance. The method includes the step of nitriding the article in a cyanide-free nitriding bath to obtain a nitrided article, heating the nitrided article in an atmosphere having nitrogen and carbon-carburizing to obtain a nitrided oxidised article. Further, in certain embodiments, the oxidised nitrided article may be coated with a metallic layer. The oxidised nitrided article with the metallic coating has improved corrosion resistance.

A method for carbonitriding of a steel part arranged in a chamber comprises first steps and second steps, a carburizing gas being injected into the chamber during the first steps only and a nitriding gas being injected into the chamber during the second steps only, at least one of the second steps being situated between two first steps, the pressure in the chamber during at least one part of said two first steps being maintained at a first value and the pressure in the chamber during at least one part of said second step situated between said two first steps being at a second value that is strictly greater than the first value.

A method for carbonitriding of a steel part arranged in a chamber comprises first steps and second steps, a carburizing gas being injected into the chamber during the first steps only and a nitriding gas being injected into the chamber during the second steps only, at least one of the second steps being situated between two first steps, the pressure in the chamber during at least one part of said two first steps being maintained at a first value and the pressure in the chamber during at least one part of said second step situated between said two first steps being at a second value that is strictly greater than the first value.

A method for the low-pressure carbonitriding of steel parts, in particular parts used in the manufacture of automobiles comprises a heating step that includes a simple heating phase (M) followed by an initial nitridation phase (Ni) from a temperature between 700° C. to 750° C. to a temperature between 860° and 1000° C. and carried out using a reduced temperature gradient relative to the simple heating phase. Additionally, alternate cementing (C1-Cn) and nitridation (N1-Nn) steps are performed at constant temperature, wherein the final nitridation step is accompanied with a decrease in temperature immediately before quenching (T).

A valve is provided, in particular an injection valve, having a valve seat and a valve needle which extends along a closing direction for the most part, the valve seat having a valve-seat surface, and a valve-closing element is mounted on an end of the valve needle facing the valve seat, the valve-closing element being able to be moved between an open position and a closed position, and the valve-closing element together with the valve-seat surface forming a sealing seat in the closed position, the valve-closing element having a greater core hardness and/or surface hardness than the valve-seat surface.

A valve is provided, in particular an injection valve, having a valve seat and a valve needle which extends along a closing direction for the most part, the valve seat having a valve-seat surface, and a valve-closing element is mounted on an end of the valve needle facing the valve seat, the valve-closing element being able to be moved between an open position and a closed position, and the valve-closing element together with the valve-seat surface forming a sealing seat in the closed position, the valve-closing element having a greater core hardness and/or surface hardness than the valve-seat surface.

A method of forming a silicon nitride film on a substrate in a vacuum vessel, includes forming the silicon nitride film by depositing a layer of reaction product by repeating a cycle a plurality of times. The cycle includes a first process of supplying a gas of a silicon raw material to the substrate to adsorb the silicon raw material to the substrate, subsequently, a second process of supplying a gas of ammonia in a non-plasma state to the substrate to physically adsorb the gas of the ammonia to the substrate, and subsequently, a third process of supplying active species obtained by converting a plasma forming gas containing a hydrogen gas for forming plasma into plasma to the substrate and causing the ammonia physically adsorbed to the substrate to react with the silicon raw material to form the layer of reaction product.

A method of forming a silicon nitride film on a substrate in a vacuum vessel, includes forming the silicon nitride film by depositing a layer of reaction product by repeating a cycle a plurality of times. The cycle includes a first process of supplying a gas of a silicon raw material to the substrate to adsorb the silicon raw material to the substrate, subsequently, a second process of supplying a gas of ammonia in a non-plasma state to the substrate to physically adsorb the gas of the ammonia to the substrate, and subsequently, a third process of supplying active species obtained by converting a plasma forming gas containing a hydrogen gas for forming plasma into plasma to the substrate and causing the ammonia physically adsorbed to the substrate to react with the silicon raw material to form the layer of reaction product.