Patent ID: 9613648
Date: 2017-04-04
CPC Classifications: B21B,B22D,C22C,C22F,C23C,C23F,G11B

Claim:
1. An aluminum alloy plate for a magnetic disk substrate wherein the aluminum alloy plate comprises an aluminum alloy containing Mg: 3.0 to 8.0 mass %, Cu: 0.005 to 0.150 mass %, Zn: 0.05 to 0.60 mass %, Cr: 0.010 to 0.300 mass %, Fe: 0.001 to 0.030 mass %, Si: 0.001 to 0.030 mass %, further containing (Ti+V+Zr):0.0010 to 0.0100 mass %, B: 0.0001 to 0.0010 mass % with a balance being Al and inevitable impurities and wherein the density of a Ti—V—B—Zr-based inclusion having a maximum diameter exceeding 5 μm is 0 piece/6000 mm