January 5, 2001 - Carpenter Micro-Melt® PD #1 alloy, a new premium grade made by powder metallurgy, may be considered for many types of cold work tooling applications that require a combination of wear resistance and good toughness.

The new alloy is an air-hardening cold work die steel that offers better wear resistance than conventional grades such as AISI Types D2, A2 and O2, while maintaining excellent toughness. In addition, it has the compressive strength required for resistance to deformation in tooling applications.

Potential applications for this alloy include punches, blanking dies, slitter knives, rotary shears, chipper knives and thread rolling dies.

The new die steel has a fine, uniform carbide distribution, which Carpenter attributes to its Micro-Melt alloy P/M process. This uniform microstructure is key to the excellent combination of properties offered by the new material.

In laboratory tests, hardness - reflecting wear resistance and compressive strength - of HRC 60.5 to HRC 63 was attained with austenitizing temperatures ranging from 1850°F (1010°C) to 2050°F (1121°C) and tempering temperature at 900°F (482°C).

Additional tests indicated that the toughness of the new Micro-Melt PD #1 alloy is greater than that of other alloys commonly used for cold work applications. The new alloy's toughness at typical working hardness levels is better than that of AISI Type A2, AISI 02, Micro-Melt M4 alloy, AISI D2 and Micro-Melt A11 alloy.

Nominal analysis of Carpenter Micro-Melt PD #1 alloy is: carbon 1.10%, manganese 0.25%, silicon 1.20%, chromium 7.75%, molybdenum 1.60%, tungsten 1.10%, vanadium 2.35%, iron balance.

The new alloy is available in round, square and flat bars, billet and powder.