A method for making a three-dimensional hierarchical layered porous copper, the method includes providing a copper-zinc alloy precursor being composed of a β′ phase and a γ phase, and treating the copper-zinc alloy precursor by electrochemical dealloying. The present application further provides a three-dimensional hierarchical layered porous copper including a first surface layer, an intermediate layer, and a second surface layer stacked in that order. The first surface layer includes a plurality of micron-scale pores and a plurality of first nanoscale pores. The intermediate layer includes a plurality of second nanoscale pores. The second surface layer includes the plurality of micron-scale pores and the plurality of first nanoscale pores.

Disclosed are a copper alloy for electrical and electronic parts and semiconductors having high strength and high electrical conductivity and a method of preparing the same. The copper alloy includes 0.09 to 0.20% by mass of iron (Fe), 0.05 to 0.09% by mass of phosphorous (P), 0.05 to 0.20% by mass of manganese (Mn), the remaining amount of copper (Cu) and 0.05% by mass or less of inevitable impurities, and has tensile strength of 470 MPa or more, hardness of 145 Hv or more, electrical conductivity of 75% IACS or more and a softening resistant temperature of 400° C. or higher.

Disclosed are a copper-cobalt-silicon-iron-phosphorus (Cu—Co—Si—Fe—P)-based alloy having strength, electrical conductivity, and excellent bending formability, and a method for producing the alloy. The copper alloy contains 1.2 to 2.5% by mass of cobalt (Co); 0.2 to 1.0% by mass of silicon (Si); 0.01 to 0.5% by mass of iron (Fe); 0.001 to 0.2% by mass of phosphorus (P); a balance amount of copper (Cu); unavoidable impurities; and optionally, 0.05% by mass or smaller of each of at least one selected from a group consisting of nickel (Ni), manganese (Mn) and magnesium (Mg), wherein a ratio between cobalt (Co) mass and silicon (Si) mass meets a relationship: 3.5≤Co/Si≤4.5, wherein a ratio between iron (Fe) mass and phosphorus (P) mass meets a relationship: 1.0<Fe/P. A bimodal structure improves the bending formability while maintaining the electrical conductivity and strength.

A copper alloy sheet material that is excellent in surface smoothness of an etched surface has a composition containing, (mass %), from 1.0 to 4.5% of Ni, from 0.1 to 1.2% of Si, from 0 to 0.3% of Mg, from 0 to 0.2% of Cr, from 0 to 2.0% of Co, from 0 to 0.1% of P, from 0 to 0.05% of B, from 0 to 0.2% of Mn, from 0 to 0.5% of Sn, from 0 to 0.5% of Ti, from 0 to 0.2% of Zr, from 0 to 0.2% of Al, from 0 to 0.3% of Fe, from 0 to 1.0% of Zn, the balance Cu and unavoidable impurities. A number density of coarse secondary phase particles has a major diameter of 1.0 μm or more of 4.0×10.sup.3 per square millimeter or less. KAM value measured with a step size of 0.5 μm is more than 3.00.

A clad material includes a first layer made of stainless steel and a second layer made of Cu or a Cu alloy and roll-bonded to the first layer. In the clad material, a grain size of the second layer measured by a comparison method of JIS H 0501 is 0.150 mm or less.

A method for preparing an alternating arrangement silver-copper lateral composite ingot, including: using a concave roller set; manufacturing a copper frame having a fixed width according to a negative tolerance of a width of the grooves of the concave roller, and corresponding copper bars and silver bars, and performing a surface treatment on the copper frame, the copper bars, and the silver bars; and then arranging different number of copper bars and silver bars at internals as needed and tightly placing into the copper frame to form a composite blank, i.e., a composite ingot. A method for preparing an alternating arrangement silver-copper lateral composite strip is further provided, and the silver-copper lateral composite ingot prepared by the method for preparing the alternating arrangement silver-copper lateral composite ingot is used to prepare the silver-copper lateral composite strip.

A clad material includes a first layer made of stainless steel and a second layer made of Cu or a Cu alloy and roll-bonded to the first layer. In the clad material, a grain size of the second layer measured by a comparison method of JIS H 0501 is 0.150 mm or less.

A hard rolled-copper foil which, when heated and laminated on an insulating resin base material, can exhibit excellent bend-resistance characteristics without increasing a final reduction ratio, which, being not prone to develop rolling marks, can maintain a low surface coarseness and can therefore be preferably used in a flexible printed wiring board having excellent high-speed transmission characteristics, which is not prone to softening at room temperature, and which provides excellent operation efficiency and foil passing property when being processed into a flexible printed wiring board after having been stored. A hard rolled-copper foil in which a crystal orientation density in a copper orientation is not less than 10, and a crystal orientation density in a brass orientation is not less than 20.

A plug-in connector and a semi-finished product include a strip of an aluminum alloy and at least one bonding layer of a copper/tin alloy electrolytically applied directly onto the aluminum alloy strip. The bonding layer has a thickness of at most 50 nm. A further metal layer or alloy layer is applied onto the bonding layer.

Described herein are thin metal strips having hot rolled exterior side surfaces characterized as being primarily or substantially free of all prior austenite grain boundaries, or at least primarily or substantially free of all prior austenite grain boundaries, and including elongated surface structure. As a result, because the prior austenite grain boundaries are not primarily or substantially present, all such prior austenite grain boundaries are not susceptible to grain boundary etching due to acid etching or pickling. In particular examples, the thin metal strips undergo hot rolling performed with a coefficient of friction equal to or greater than 0.20 with or without use of lubrication.