A method for forming holes to form holes in a surface of a metal part includes: putting the metal part into a first solution as an anode; applying a first voltage on the metal part to form the first holes in a surface of the metal part; and cleaning and drying the metal part with the first holes. The first solution comprises a first organic solvent, chloride, and a phosphoric acid compound. The disclosure also provides a metal product and a metal composite.

A method for forming holes to form holes in a surface of a metal part includes: putting the metal part into a first solution as an anode; applying a first voltage on the metal part to form the first holes in a surface of the metal part; and cleaning and drying the metal part with the first holes. The first solution comprises a first organic solvent, chloride, and a phosphoric acid compound. The disclosure also provides a metal product and a metal composite.

Disclosed is an apparatus and method for forming lubricant recesses having minute configurations by applying a photolithograph method in a curved inner surface, such as a cylinder bore surface of a cylinder block, the inside of a cylinder liner, the inside of a compressor cylinder, a big end of a connecting rod, a big end bearing, a shaft insertion hole of a rocker arm, or the like in an internal combustion engine.

Disclosed is an apparatus and method for forming lubricant recesses having minute configurations by applying a photolithograph method in a curved inner surface, such as a cylinder bore surface of a cylinder block, the inside of a cylinder liner, the inside of a compressor cylinder, a big end of a connecting rod, a big end bearing, a shaft insertion hole of a rocker arm, or the like in an internal combustion engine.

A method for producing round stock (10) which is provided with at least one inscription and/or marking (16), at least the surface (12) of the round stock (10) consisting of a metallic material, in particular of chromium or steel, for example of hardened steel, chromium-plated steel or stainless steel. In order to improve this method such that disadvantages and shortcomings are avoided, the method includes the following steps: placing on the surface (12) at least one cover (20) which is adapted to the shape of the surface (12) and in particular has the inscription and/or marking (16), such that the region to be provided with the inscription and/or marking (16) is not covered by the cover (20),—exposing the round stock (10) to a first electrolyte (30) together with the cover (20), material being removed from the surface (12) by said electrolyte in the region to be provided with the inscription and/or the marking (16) while producing depressions (14), and—exposing the round stock (10) together with the cover (20) and the depressions (14) not covered by the cover (20) to a second electrolyte (32) by which the depressions (14) are filled to produce the inscription and/or marking (16) which differs from the surface (12) optically, in particular with respect to color. The present invention also relates to round stock (10) which is manufactured from a metallic material, with the round stock being provided with a correspondingly produced inscription and/or marking (16).

A method for producing round stock (10) which is provided with at least one inscription and/or marking (16), at least the surface (12) of the round stock (10) consisting of a metallic material, in particular of chromium or steel, for example of hardened steel, chromium-plated steel or stainless steel. In order to improve this method such that disadvantages and shortcomings are avoided, the method includes the following steps: placing on the surface (12) at least one cover (20) which is adapted to the shape of the surface (12) and in particular has the inscription and/or marking (16), such that the region to be provided with the inscription and/or marking (16) is not covered by the cover (20),—exposing the round stock (10) to a first electrolyte (30) together with the cover (20), material being removed from the surface (12) by said electrolyte in the region to be provided with the inscription and/or the marking (16) while producing depressions (14), and—exposing the round stock (10) together with the cover (20) and the depressions (14) not covered by the cover (20) to a second electrolyte (32) by which the depressions (14) are filled to produce the inscription and/or marking (16) which differs from the surface (12) optically, in particular with respect to color. The present invention also relates to round stock (10) which is manufactured from a metallic material, with the round stock being provided with a correspondingly produced inscription and/or marking (16).

A method of forming a surface texture includes arranging a flexible mask (610, 920) with a pattern over a surface (621) of a component (620); and performing electrochemical etching on the surface (621) of the component (620) to form a surface texture on the surface (621) according to the pattern of the flexible mask.

A method of forming a surface texture includes arranging a flexible mask (610, 920) with a pattern over a surface (621) of a component (620); and performing electrochemical etching on the surface (621) of the component (620) to form a surface texture on the surface (621) according to the pattern of the flexible mask.

Provided are stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, and a method of manufacturing the same. In the stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, according to an embodiment of the present invention, a ratio of Cr hydroxide/Cr oxide included in a passivation film of the stainless steel ranges from 0.7 to 1.6, and the passivation film has a contact angle (θ) of 70° or less. Thus, not only corrosion resistance may be enhanced by removing a non-conductive film formed on a surface of the stainless steel and forming a new conductive film thereon, but hydrophilicity may also be secured without additional surface treatment such as a separate coating or the like, and thus manufacturing costs may be reduced and productivity may be increased.

Provided are stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, and a method of manufacturing the same. In the stainless steel for a separator of a polymer electrolyte membrane fuel cell, which exhibits enhanced hydrophilicity and enhanced corrosion resistance, according to an embodiment of the present invention, a ratio of Cr hydroxide/Cr oxide included in a passivation film of the stainless steel ranges from 0.7 to 1.6, and the passivation film has a contact angle (θ) of 70° or less. Thus, not only corrosion resistance may be enhanced by removing a non-conductive film formed on a surface of the stainless steel and forming a new conductive film thereon, but hydrophilicity may also be secured without additional surface treatment such as a separate coating or the like, and thus manufacturing costs may be reduced and productivity may be increased.