In a sliding member, fatigue resistance of a surface layer formed by dispersing a hard material in a soft metal matrix is improved. A sliding member includes a base material layer and a surface layer, the surface layer includes a metal matrix and a hard material harder than the matrix and dispersed in the matrix, the hard material has a gradient in hardness, and the gradient in hardness gradually decreases from an inner side to a surface of the hard material.

A manufacturing method of copper foil and circuit board assembly for high frequency transmission are provided. Firstly, a raw copper foil having a predetermined surface is produced by an electrolyzing process. Subsequently, a roughened layer including a plurality of copper particles is formed on the predetermined surface by an arsenic-free electrolytic roughening treatment and an arsenic-free electrolytic surface protection treatment. Thereafter, a surface treatment layer is formed on the roughened layer, and the roughened layer is made of a material which includes at least one kind of non-copper metal elements and the concentration of the non-copper metal elements is smaller than 400 ppm. By controlling the concentration of the non-copper elements, the resistance of the copper foil can be reduced.

A manufacturing method of copper foil and circuit board assembly for high frequency transmission are provided. Firstly, a raw copper foil having a predetermined surface is produced by an electrolyzing process. Subsequently, a roughened layer including a plurality of copper particles is formed on the predetermined surface by an arsenic-free electrolytic roughening treatment and an arsenic-free electrolytic surface protection treatment. Thereafter, a surface treatment layer is formed on the roughened layer, and the roughened layer is made of a material which includes at least one kind of non-copper metal elements and the concentration of the non-copper metal elements is smaller than 400 ppm. By controlling the concentration of the non-copper elements, the resistance of the copper foil can be reduced.

Embodiments of this application disclose an electrical connector, including at least one first conductive terminal and at least one second conductive terminal, where a first electroplated layer is disposed on an outer surface of the first conductive terminal, a second electroplated layer is disposed on an outer surface of the second conductive terminal, and a material of the second electroplated layer is different from a material of the first electroplated layer. Electroplating costs of the electrical connector are reduced while corrosion resistance of the electrical connector is ensured. The embodiments of this application further disclose a mobile terminal and an electrical connector manufacturing method.

Embodiments of this application disclose an electrical connector, including at least one first conductive terminal and at least one second conductive terminal, where a first electroplated layer is disposed on an outer surface of the first conductive terminal, a second electroplated layer is disposed on an outer surface of the second conductive terminal, and a material of the second electroplated layer is different from a material of the first electroplated layer. Electroplating costs of the electrical connector are reduced while corrosion resistance of the electrical connector is ensured. The embodiments of this application further disclose a mobile terminal and an electrical connector manufacturing method.

A pin terminal includes a bar-like base material and a plating layer covering a predetermined region of the base material. A constituent material of the base material is pure copper or a copper alloy. The plating layer includes a tin-based layer made of metal containing tin. One end side of the base material includes a tip covering portion covering an entire region in a circumferential direction of the base material. The tin-based layer includes the tip covering portion. The tip covering portion includes a thin film portion and a thick film portion at positions different in the circumferential direction of the base material. The thin film portion includes an outer layer and an inner layer provided in contact with the base material. A constituent material of the outer layer is pure tin, and that of the inner layer is an alloy containing tin and copper.

A pin terminal includes a bar-like base material and a plating layer covering a predetermined region of the base material. A constituent material of the base material is pure copper or a copper alloy. The plating layer includes a tin-based layer made of metal containing tin. One end side of the base material includes a tip covering portion covering an entire region in a circumferential direction of the base material. The tin-based layer includes the tip covering portion. The tip covering portion includes a thin film portion and a thick film portion at positions different in the circumferential direction of the base material. The thin film portion includes an outer layer and an inner layer provided in contact with the base material. A constituent material of the outer layer is pure tin, and that of the inner layer is an alloy containing tin and copper.

An electrode for a lithium-ion battery. The electrode has at least one porous silicon layer and a copper layer. There is also described a battery with such an electrode, a method for producing an electrode of this kind, and the use of an electrode of this kind in a battery.

An electrode for a lithium-ion battery. The electrode has at least one porous silicon layer and a copper layer. There is also described a battery with such an electrode, a method for producing an electrode of this kind, and the use of an electrode of this kind in a battery.

A structure includes a copper or copper alloy plating layer, in which Kirkendall void formation is suppressed. The copper or copper alloy plating layer is formed by electroplating at a prescribed first cathode current density by using a copper or copper alloy electroplating bath and then completing the electroplating after the first cathode current density is changed to a lower second cathode current density. The first cathode current density is a single cathode current density in the electroplating at this current density or an average cathode current density in the electroplating by combining plural cathode current densities. The first cathode current density is at lowest 5 A/dm.sup.2. A layer formed by changing the first cathode current density to the second cathode current density is a surface layer part of the copper or copper alloy plating layer, which can have a thickness of 0.05 μm to 15 μm.