The invention concerns a method for manufacturing a process apparatus for moving liquid in high temperature liquid immersion under aggressive chemical environment and dynamic stress, wherein the method comprises the step of lining the process apparatus formed of stainless steel with rubber, wherein the method further comprises the step of forming a passivation layer on a surface of the process apparatus in an acid bath prior to lining the process apparatus comprising the passivation layer with rubber. The invention also concerns a process apparatus.

The tendency of a bare metal surface to oxidize (e.g., flash-rust) may be alleviated by contacting the bare metal surface with an aqueous mixture of at least one preformed reaction product obtained by reaction of at least one catechol compound, such as dopamine or a salt thereof, with at least one co-reactant compound functionalized with one or more functional groups reactive with the at least one catechol compound, such as (meth)acryl, primary amino, secondary amino, thiol and/or hydroxyl groups, with polyethyleneimine being an example of a suitable co-reactant compound. Such a rinsing procedure does not interfere with subsequent conversion coating of the metal surface.

The tendency of a bare metal surface to oxidize (e.g., flash-rust) may be alleviated by contacting the bare metal surface with an aqueous mixture of at least one preformed reaction product obtained by reaction of at least one catechol compound, such as dopamine or a salt thereof, with at least one co-reactant compound functionalized with one or more functional groups reactive with the at least one catechol compound, such as (meth)acryl, primary amino, secondary amino, thiol and/or hydroxyl groups, with polyethyleneimine being an example of a suitable co-reactant compound. Such a rinsing procedure does not interfere with subsequent conversion coating of the metal surface.

The present invention relates to a solution composition capable of improving pitting corrosion resistance and blackening resistance of a steel sheet, a steel sheet surface-treated using same, and a method for manufacturing the steel sheet.

A process for surface activation or depassivation of an article, in particular an alloy, by immersion of the alloy in an aqueous acid solution. The surface activation methods of the present invention can be performed during a relatively short period of time and achieve reductions in production costs and provide environmental friendliness as compared to prior art processes. In a further embodiment, after surface activation, the article is immersed in a second liquid that prevents re-formation of a passivating oxide layer on the surface of the article. In a further embodiment the surface-activated alloys are subjected to surface engineering by a process that infuses carbon or nitrogen through the surface at a temperature sufficiently low to suppress precipitation of carbides or nitrides.

A process for surface activation or depassivation of an article, in particular an alloy, by immersion of the alloy in an aqueous acid solution. The surface activation methods of the present invention can be performed during a relatively short period of time and achieve reductions in production costs and provide environmental friendliness as compared to prior art processes. In a further embodiment, after surface activation, the article is immersed in a second liquid that prevents re-formation of a passivating oxide layer on the surface of the article. In a further embodiment the surface-activated alloys are subjected to surface engineering by a process that infuses carbon or nitrogen through the surface at a temperature sufficiently low to suppress precipitation of carbides or nitrides.

A method of making a treated article having a metal surface. The method includes treating the metal surface with a primer composition comprising a secondary or tertiary amino-functional compound having at least two independently selected silane groups to provide a primed metal surface and subsequently treating the primed metal surface with a treatment composition comprising a fluorinated compound represented by formula Rf{X[Si(Y).sub.3-x(R).sub.x].sub.y}.sub.z. An article treated by such a method is also disclosed. The use of a secondary or tertiary amino-functional compound having at least two independently selected silane groups as a primer for a metal surface before treatment with the fluorinated silane and a method of treating a metal surface with a treatment composition including the secondary or tertiary amino-functional compound having at least two independently selected silane groups and certain fluorinated silanes are also disclosed

A method of making a treated article having a metal surface. The method includes treating the metal surface with a primer composition comprising a secondary or tertiary amino-functional compound having at least two independently selected silane groups to provide a primed metal surface and subsequently treating the primed metal surface with a treatment composition comprising a fluorinated compound represented by formula Rf{X[Si(Y).sub.3-x(R).sub.x].sub.y}.sub.z. An article treated by such a method is also disclosed. The use of a secondary or tertiary amino-functional compound having at least two independently selected silane groups as a primer for a metal surface before treatment with the fluorinated silane and a method of treating a metal surface with a treatment composition including the secondary or tertiary amino-functional compound having at least two independently selected silane groups and certain fluorinated silanes are also disclosed

A ferritic stainless steel excellent in corrosion resistance and conductivity and a method for manufacturing the same, the stainless steel having a chemical composition containing, by mass %, C: 0.001% or more and 0.05% or less, Si: 0.001% or more and 0.5% or less, Mn: 0.001% or more and 1.0% or less, Al: 0.001% or more and 0.5% or less, N: 0.001% or more and 0.05% or less, Cr; 17% or more and 23% or less, Mo: 0.1% or less and the balance being Fe and inevitable impurities and a passivation film on the surface of the stainless steel which is obtained by immersing the stainless steel in a solution for an immersion treatment, said solution mainly contains hydrofluoric acid or a liquid mixture of hydrofluoric acid and nitric acid.

Assemblies of stacked layers of materials are described. The assemblies include functional and structural layers. Functional layers include binderless ceramic materials on woven or non-woven substrates of natural, synthetic, or metallic materials. The layers of functional and structural materials may be configured to transport moisture or heat from an inner surface to an outer surface that is exposed to an ambient environment.