Mechanomaking of high speed steel AISI M2: powder consolidation

AISI M2 powders were produced from the elements by mechanomaking, a room temperature process driven by high energy ball milling. The as-mechanomade powders with relative densities 0.5, were consolidated by cold and then hot isostatic pressing. Fully dense solids with carbide sizes around 20 nm are obtained after Hot Isostatic Pressing (HIP) at 950°C, while the matrix is constituted of a very fine array of crystallites below 10 nm. An as-quenched hardness of 69 HRC was obtained and a Hall-Petch behavior was observed for Vickers hardness. No evidence of residual austenite was found in either as-HIPed or quenched samples.