Abstract: It is supposed that N is defined as an optional natural number equal to or more than 3. A key wrench has a key section 5-2 engageable with a socket 2 of an N-sided polygon, and a proximal section 5-1. The key section 5-2 has N side surfaces that contain a first side surface 50-1, a second side surface 50-2 and an Nth side surface 50-N. The first side surface 50-1 is a tapered surface, and the Nth side surface 50-N is a non-tapered surface. Thus, the key wrench is provided to restrain a transformation of the surface of the socket and a generation of an excessive cam out load.

Abstract: Disclosed herein is an electrically conductive material including a base material made of a copper alloy sheet strip, a Cu—Sn alloy coating layer and a reflow Sn coating layer, wherein the Cu—Sn alloy coating layer and the reflow Sn coating layer are arranged on a surface of the base material in this order from a side of the base material, parts of the Cu—Sn alloy coating layer are exposed on a surface, a coefficient of friction in each of a direction perpendicular to and a direction inclined by 45° to a rolling direction of the copper alloy base material is reduced, compared to that in the rolling direction of the copper alloy base material.

Abstract: The present invention relates to a Cu—Ni—Sn—P-based copper alloy sheet having a specific composition, where (1) the copper alloy sheet is set to have an electrical conductivity of 32% IACS or more, a stress relaxation ratio in the direction parallel to the rolling direction of 15% or less, a 0.

Abstract: A copper alloy with an excellent stress relaxation resistance including Ni: 0.1 through 3.0 mass %, Sn: 0.01 through 3.0 mass %, P: 0.01 through 0.3 mass % and remainder copper and inevitable impurities, and the Ni content in extracted residues separated and left on a filter having filter mesh size of 0.1 ?m by using an extracted residues method accounting for 40 mass % or less of the Ni content in the copper alloy, wherein the extracted residues method requires that 10 g of the copper alloy is immersed in 300 ml of a methanol solution which contains 10 mass % of ammonium acetate, and using the copper alloy as the anode and platinum as the cathode, constant-current electrolysis is performed at the current density of 10 mA/cm2, and the solution in which the copper alloy is thus dissolved is subjected to suction filtration using a membrane filter of polycarbonate whose filter mesh size is 0.

Abstract: A copper alloy with an excellent stress relaxation resistance including Ni: 0.1 through 3.0 mass %, Sn: 0.01 through 3.0 mass %, P: 0.01 through 0.3 mass % and remainder copper and inevitable impurities, and the Ni content in extracted residues separated and left on a filter having filter mesh size of 0.1 ?m by using an extracted residues method accounting for 40 mass % or less of the Ni content in the copper alloy, wherein the extracted residues method requires that 10 g of the copper alloy is immersed in 300 ml of a methanol solution which contains 10 mass % of ammonium acetate, and using the copper alloy as the anode and platinum as the cathode, constant-current electrolysis is performed at the current density of 10 mA/cm2, and the solution in which the copper alloy is thus dissolved is subjected to suction filtration using a membrane filter of polycarbonate whose filter mesh size is 0.

Abstract: Provided is a copper alloy for electrical or electronic parts which is superior in yield strength, electric conductivity, spring limit value, resistance property of stress relaxation, bendability and Sn plating property. The copper alloy for electrical or electronic parts comprises Fe: 0.5-2.4% (“%” means “% by mass”, which is the same hereinafter.), Si: 0.02-0.1%, Mg: 0.01-0.2%, Sn: 0.01-0.7%, Zn: 0.01-0.2%, Pb: 0.0005-0.015%, P: less than 0.03%, Ni: 0.03% or less, and Mn: 0.03% or less, and further comprises Cu and inevitable impurities as the balance of the copper alloy.

Abstract: A copper alloy which is adapted for use as terminals and connectors, which comprises from 0.1 wt % to less than 0.5 wt % of Ni, from larger than 1.0 wt % to less than 2.5 wt % of Sn, from larger than 1.0 wt % to 15 wt % of Zn, and further comprises from at least one element selected between from 0.0001 wt % to less than 0.05 wt % of P and from 0.0001 wt % to 0.005 wt % of Si, and the balance being Cu and inevitable impurities The alloy has an electrical conductivity of 90% or below relative to a maximum electrical conductivity of an annealed copper alloy and an area ratio of insoluble matters such as precipitates is 5% or below.