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.

A method of improving corrosion resistance of a metal substrate comprising a zinc surface coated with zirconium oxide conversion coating by, prior to conversion coating, contacting the zinc surface with a composition comprising: a) iron(III) ions, b) a source of hydroxide ion; c) at least one complexing agent selected from organic compounds which have at least one functional group COOX, wherein X represents either a H or an alkali and/or alkaline earth metal; d) 0.0 to about 4 g/l cobalt (II) ions; and optionally e) a source of silicate: wherein the composition has a pH of at least 10.

Surface treatment methods for Ni-based metallic glasses are provided that promote passivation and decrease the amount of Ni released when the Ni-based metallic glass is exposed to a saline containing environment.

Embodiments of the present disclosure provide a surface treatment composition and methods for using same. The composition for removing contaminants from a metallic surface, can include 3 wt % to 40 wt % of at least one bifunctional alkaline compound, 0.03 wt % to 10 wt % of at least one oxidizer comprising a metal salt, and water, where all weight percentages are based on the total weight of the composition.

The present invention relates to a magnesium alloy material, which is an in situ magnesium hydroxide nanosheet layer modified magnesium alloy. The material is prepared from a magnesium alloy through a hydrothermal reaction under alkaline condition. The protective effect of the in situ formed magnesium hydroxide nanosheet layer structure results in remarkably enhanced corrosion resistance of the magnesium alloy, meanwhile the biocompatibility can also be significantly improved since the release rate of magnesium ion can be significantly reduced. In addition, the two-dimensional nanolayer structure has a non-releasing physical antibacterial property depending on contact. Therefore, the magnesium alloy material according to the present invention has an extremely great application prospect in the field of medical implant.

The present invention relates to a magnesium alloy material, which is an in situ magnesium hydroxide nanosheet layer modified magnesium alloy. The material is prepared from a magnesium alloy through a hydrothermal reaction under alkaline condition. The protective effect of the in situ formed magnesium hydroxide nanosheet layer structure results in remarkably enhanced corrosion resistance of the magnesium alloy, meanwhile the biocompatibility can also be significantly improved since the release rate of magnesium ion can be significantly reduced. In addition, the two-dimensional nanolayer structure has a non-releasing physical antibacterial property depending on contact. Therefore, the magnesium alloy material according to the present invention has an extremely great application prospect in the field of medical implant.

An object of the present invention is to provide a treatment liquid and a treatment method that are capable of enhancing the corrosion resistance of a metal material. This object is achieved by, after forming a chemical conversion treatment film on the surface of a metal material, forming a film using a film-forming treatment liquid, the treatment liquid comprising: a silicon compound containing at least one member selected from the group consisting of alkoxysilyl, alkoxysilylene, and a siloxane bond; an organometallic compound; and water.

Disclosed is a zirconium-based metal pretreatment coating composition that includes a metal chelator that chelates copper in the metal pretreatment coating composition and thereby improves adhesion of paints to a metal substrate coated with the pretreatment coating composition and the chelating agent is present in a sufficient amount to ensure that in the deposited pretreatment coating on the metal substrate the average total atomic % of copper to atomic % of zirconium is equal to or less than 1.1. The pretreatment coating composition is useful for treating a variety of metal substrates.

A method of improving corrosion resistance of a metal substrate comprising a zinc surface coated with zirconium oxide conversion coating by, prior to conversion coating, contacting the zinc surface with a composition comprising: a) iron(III) ions, b) a source of hydroxide ion; c) at least one complexing agent selected from organic compounds which have at least one functional group COOX, wherein X represents either a H or an alkali and/or alkaline earth metal; d) 0.0 to about 4 g/l cobalt (II) ions; and optionally e) a source of silicate: wherein the composition has a pH of at least 10.