Process and Main characteristics
The molten steel is poured from a big tundish which allows to run down a fine jet of molten steel into an atomization chamber. At the top of the chamber the steel is fragmented into a shower of steel droplets by high-speed gas jets. When the droplets have reached the bottom of the chamber, they have solidified. Each powder grain (droplet) has the same chemical composition as a full size conventional ingot but the size has been reduced to less than one mm and the weight has at the same time been reduced from about 400 kg to 0,000004 kg. Reduction of the ingot size is the same as to reduce the segregation problem that limits the strength of the material. The powder is filled into metal cylinders (capsules) sealed by welding after vacuum evacuation. After preheating the cylinders are hot-isostatic pressed to full density billets. The final products are obtained after forging or rolling, heat treatments and final quality inspections
To achieve good cutting performance from PM HSS, an appropriate hardening response must be provided in heat treatment. Properly performed heat treatment can significantly influence the finite properties of high-speed steel, so the heat treatment parameters are chosen depending on the specific properties of the particular tool. The high-speed steel heat treatment consists of austenitization in a protective atmosphere, quenching and three high temperature tempering treatments.
ASP® steels are produced by powder metallurgy through a 3-step process: gas-atomization, Hot Isostatic Pressing and post processing operations such as forging, rolling or drawing.
The ASP® range is suitable for a wide range of tooling and component applications, like ASP®2055 with cobalt for gear cutting, ASP®2030 for taps and ASP®2005 for the cold work.