Patent ID: 7422804
Filing Date: 2008-09-09
Classification: C23C,Y10T

Abstract:
1. A method for inhibiting the metal dusting of metal apparatus having surfaces exposed to carbon supersaturated environments comprising: constructing said metal apparatus according to the following composition: (a) a metal substrate, (b) a titanium alloy layer on said metal substrate capable of forming a thermally stable carbide coating on the titanium alloy surface when exposed to a carbon supersaturated environment, wherein said titanium alloy layer comprises at least 50 wt % of a metal chosen from Fe, Ni, Co, and mixtures thereof, at least 10 wt % Ti, at least 15 wt % Cr; and about 0.1 wt % to about 25 wt % of alloying components chosen from Mn, Al, Si, Y, Zr, Hf, V, Nb, Ta, Mo, W, Re, Cu, Sn, Ga, C, O, N and mixtures thereof; and exposing the titanium alloy layer to a carbon supersaturated, low oxygen partial pressure atmosphere at a temperature and for a time sufficient to form a metal dusting inhibiting protective coating on the surface of the titanium alloy layer, wherein (c) said protective coating on the surface of said titanium alloy layer comprises an outer titanium oxide layer and an inner carbide layer between the surface of the titanium alloy layer and the outer oxide layer.