Patent GB-764362-A (GB)
Title: Improvements in or relating to the provision of coatings on titanium and its alloys
IPC: C23C22/34
Filed: 1955-02-04
Abstract: A composition for the production of coatings on titanium or titanium-base alloys comprises a solution or homogenous dispersion comprising 1-20 g/litre of hydrofluoric, hydrofluosilicic or fluoboric acid or a mixture of any of these and 3-300 g/litre of an organic lubricant resistant to the action of said acids, the remainder of the composition constituting a vehicle resistant to the attack of said acids.  As lubricants may be used one or more of paraffin wax, e.g. petroleum paraffin wax, chlorinated paraffin wax, a saturated straight-chain fatty acid, preferably having a chain length of at least 12 carbon atoms, e.g. stearic, oleic, lauric or myristic acid, a glyceride of such a fatty acid or aluminium stearate.  When the composition is in the form of a solution, the solvent system may comprise one or more of methyl isobutyl carbinol, n- or tertiary-butyl alcohol, butyl or hexyl "Cellosolve" (Registered Trade Mark), butyl "carbitol," mineral spirits of petroleum origin, such as kerosene, high-flash naphtha, hydrogenated petroleum solvent or pine oil.  When the composition is in the form of a dispersion, the medium is water containing a thickening or emulsifying agent, e.g. high viscosity methyl cellulose or polyoxyethylene lauryl alcohol in which the ethylene oxide chain length is 4 or 12.  5-20 g/litre of phosphoric acid may be added to the composition for the treatment of certain alloys.ALSO:A composition for the production of coatings on titanium or titanium-base alloys comprises a solution or homogeneous dispersion comprising 1-20g/litre of hydrofluoric, hydrofluosilicic or fluoboric acid or a mixture of any of these and 3-300g/litre of an organic lubricant resistant to the action of said acids, the remainder of the composition constituting a vehicle resistant to the attack of said acids.  As lubricant may be used one or more of paraffin wax, e.g. petroleum paraffin wax, chlorinated paraffin wax, a saturated straight-chain fatty acid, preferably having a chain length of at least 12 carbon atoms, e.g. stearic, oleic, lauric or myristic acid, a glyceride of such a fatty acid, or aluminium stearate.  When the composition is in the form of a solution, the solvent system may comprise one or more of methyl isobutyl carbinol, butyl or hexyl "Cellosolve" (Registered Trade Mark), butyl "carbitol," n-or tertiary-butyl alcohol, mineral spirits of petroleum origin, such as kerosene, high-flash naphtha, hydrogenated petroleum solvent or pine oil. When the composition is in the form of a dispersion, the medium is water containing a thickening or emulsifying agent e.g. high viscosity methyl cellulose or polyoxethylene lauryl alcohol in which the theylene oxide chain length is 4 or 12, 5-20g/litre of phosphoric acid may be added to the composition especially for the treatment of certain alloys such as that composed of 92 per cent titanium, 4 per cent aluminium and 4 per cent manganese.  The coatings produced are stated to reduce the tendency of the metal to gall when in frictional contact with other metal surfaces or during cold-working.