Patent ID: 7799388

Claim:
A method for forming a mechanical seal structure comprising the steps of (i) forming a shaped substrate and (ii) applying a ceramic seal face layer to the substrate by thermal spraying further comprising the steps of (a) forming a free flowing agglomerate comprising: (i) 30 to about 97 weight percent silicon carbide (ii) silicon and (iii) a carbon containing binder; (b) feeding the free flowing agglomerate into a thermal spray apparatus, (c) spraying the silicon carbide and silicon onto the substrate, whereby the silicon carbide and silicon deposit on the surface of the substrate, and (d) keeping the deposited silicon on the substrate surface at a temperature which is at least 0.75 times the melting temperature in Kelvin of the silicon and at most 100 K above the melting temperature of the silicon during the spraying at least in the region where the silicon and silicon carbide actually strike the surface.