Process for producing a die plate for underwater granulation of plastic material with an intermediate nickel alloy layer

Abstract

A die plate for the underwater granulation of thermoplastic material is formed with a base plate of an iron alloy, a hard annular cutting plate of titanium-carbide alloy, and an intermediate buffer layer containing nickel between the base plate and the cutting plate to equilibrate heat stresses due to different coefficient of thermal expansion of the base and the cutting plates. The intermediate layer is formed with a thickness of between 0.5 and 2 mm by hot-isostatic pressing a nickel-containing metal powder between the plates such that the intermediate layer is diffusion welded to the plates. Two nickel layers with an intermediate titanium-containing plate can also be formed. Also an ansenitic layer can be formed between the nickel layer and the base plate.

Dependencies are inferred from the claim text.