Abstract: With a grooved-inner-surface heat transfer tube, an inner circumferential surface of a metal tube is formed with fins bent at bent portions in a zigzag and extending consecutively around a circumferential direction of the inner circumferential surface, and at at least a part of the bent portions of the fins, the height of the fins is set at 30 to 90% of the height of the fins excluding the bend portions. With such a heat transfer tube, pressure loss can be suppressed while increasing heat exchange performance.

Abstract: A lead frame material comprises a base plate consisting of copper or copper alloys, and a protective coating formed on the upper or the both surface of the base plate. The protective coating is composed of at least one metal selected from the group consisting of gold, gold alloy, silver, silver alloy, palladium and palladium alloy, and has a thickness of 10-500 angstrom. The protective coating is formed by means of vapor deposition. It is possible to form an intermediate coating of nickel or nickel alloys between the surface of the base plate and the protective coating, by means of vapor deposition or wet plating. The suitable thickness of the intermediate coating is within the range of 50-20000 angstrom.

Abstract: A copper based alloy for use as a material for electrical and electronic parts has a chemical composition by weight, of 0.5 to 3% Ni, 0.1 to 0.9% Sn, 0.08 to 0.8% Si, 0.1 to 3 Zn, 0.007 to 0.25% Fe, 0.001 to 0.2% P, 0.001 to 0.2% Mg, 0.0001 to 0.001% C, and if required, further containing 0.001 to 0.3% at least one element of Cr and Zr, and the balance being Cu and inevitable impurities. The obtained copper alloy is excellent in electric conductivity, solder-exfoliation resistance when bent, high-temperature creep strength, and migration resistance, while being superior in hot workability and blankability to the conventional copper based alloy.

Abstract: A copper-based alloy connector excellent in electrical conductivity, adherence of solder of the connector when bent, high-temperature creep strength, and migration resistance, consists essentially by weight percent of 0.5 to 3% Ni, 0.1 to 0.9% Sn, 0.08 to 0.8% Si, 0.1 to 3% Zn, 0.007 to 0.25% Fe, 0.001 to 0.2% P, and the balance of Cu and inevitable impurities. The copper-based alloy connector can withstand use for a long term in a high-temperature and high-humidity environment.