US Patent:
20060231167, Oct 19, 2006
Inventors:
Marshall Hillstrom - New Brighton MN, US
International Classification:
C22C 38/22
Abstract:
Tough, wear-resistant dies derived from cold work steel formed by powder metallurgy processing and containing not greater than about 4% of tungsten. The dies desirably contain not greater than about 4% molybdenum by weight and at least about 5% chromium by weight. Disclosed also is a punch and die combination, the die being derived from cold work steel formed by powder metallurgy processing and containing not greater than about 4% of tungsten. The punch, which may also be derived from cold work steel formed by powder metallurgy processing and containing less than about 4% by weight of tungsten, may have a formula different from that of the die. A punching method is also disclosed.