Wear resistant oxide coating for hard metals, esp. tools - made by chemical vapour deposition using organo-metallic cpd. to form oxides or mixed oxides (OE 15.5.79)

摘要

The hard metal substrate is coated with a metal layer, followed by a hard oxide layer deposited via thermal or chemical decompsn. of organic cpds. in the gaseous phase. The organic cpds. of Al, Si, Ge, Sn, Mg, Ti, Ca, Cr, Zr, and/or the lanthanides are pref. used to form a layer of oxides or mixed oxides of these elements. The pref. organic cpds. are metal-organic cpds., alcoholates, chelates, or salts, more pref. trimethyltriethyl-, and/or triisopropyl- Al; Al phenolate; Al-Mg-ethoxide; or Al acetyl-acetonate (AAA). The deposition of the oxide layer is pref. at 900-1100 degrees C, using a carrier gas of H2 and CO2 for the organic cpd. The invention provides increased working life for tools.