HIGH STRENGTH, HIGH CONDUCTIVITY AND HIGH HEAT RESISTANCE COPPER BASE ALLOY AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a copper base alloy maintaining electric conductivity, tensile strength and Vickers hardness equal to or above the specified value even after heating at a specified temp. for a specified time by producing it by using an ingot of a copper base alloy contg. specified rations of iron, phosphorus and zinc. ;SOLUTION: This high strength, high conductivity and high heat resistance copper base alloy is produced by using an ingot of a copper base alloy contg., by weight, 2.0 to 2.5% iron, 0.01 to 0.2% phosphorus and 0.01 to 1% zinc, has ≥70% IACS electric conductivity and ≥520 N/mm2 tensile strength and maintains the value of ≥90% of Vickers hardness of ≥155 Hv even after heating at 450°C for 5 min. An ingot of a copper base alloy is hot-rolled at 800 to 1,050°C, is thereafter cold-rolled, is held at ≥900°C for ≥30 sec and is immediately cooled to 500°C at a cooling rate of ≥100°C/min. After that, it is cold-rolled, is annealed at 550 to 650°C for 30 min to 6 hr, is moreover annealed at 400 to 525°C for 1 to 10 hr and is cold-rolled so as to control the finish rolling working ratio to 70 to 85% to obtain a copper base alloy suitable for a lead frame material or the like.;COPYRIGHT: (C)2001,JPO