ALUMINUM ALLOYS FOR HIGH-TEMPERATURE AND HIGH-SPEED FORMING, PROCESSES FOR PRODUCTION THEREOF, AND PROCESS FOR PRODUCTION OF ALUMINUM ALLOY FORMS

摘要

An aluminum alloy material for high-temperature/high-speed molding containing 2.0 to 8.0 mass% of Mg, 0.05 to 1.0 mass% of Mn, 0.01 to 0.3 mass% of Zr, 0.06 to 0.4 mass% of Si and 0.06 to 0.4 mass% of Fe, with the balance being made of aluminum and inevitable impurities; an aluminum alloy material for high-temperature/high-speed molding containing 2.0 to 8.0% of Mg, 0.05 to 1.5% of Mn and 0.05 to 0.4% of Cr, Fe being restricted to 0.4% or less and Si being restricted to 0.4% or less, the grain diameter of a Cr-base intermetallic compound formed by melt-casting being 20 µm or less, and grains of intermetallic compounds with a grain diameter in the range from 50 to 1,000 nm as Mn-base and Cr-base precipitates being present in a distribution density of 350,000 grains/mm² or more, the aluminum alloy material being used for high-temperature/high-speed molding by subjecting the alloy material to cooling at a cooling rate of 20°C/min or more immediately after molding at a temperature range from 200 to 550°C and at a strain rate from 10^-2 to 10/sec; and a method of producing the aluminum alloy material.