Disclosed herein is a method of coating, comprising providing an article having an internal passage therein to be coated; electrolytically applying a first layer that comprises chromium or a chromium alloy onto a surface of the internal passage; electrolytically applying a second layer comprising aluminum or an aluminum alloy onto the first layer; and heat treating the article to promote interdiffusion between the first layer and the second layer.

A system for coating an interior surface of a heat exchanger includes a tank for storing the coating solution, a pump, a source line for supplying the coating solution to the heat exchanger, and a return line for returning the remainder of the coating solution to the tank. The system can include a pre-treatment line for supplying a pre-treatment solution to the heat exchanger and a water line for supplying water to the heat exchanger. An air compressor can be coupled to the heat exchanger to force the coating solution, the pre-treatment solution, or the water from the heat exchanger.

A film forming apparatus is connected to a carbon steel purification system piping of a BWR plant (S1). Formic acid (surface purification agent) is injected into a circulation piping of the film forming apparatus (S4). A surface purification agent aqueous solution containing 30000 ppm of formic acid is contacted with the inner surface of the purification system piping, and a large amount of Fe.sup.2+ is dissolved from the purification system piping, and a large amount of electrons are generated by this dissolution. Thereafter, a formic acid Ni aqueous solution is injected into the surface purification agent aqueous solution to produce a film forming aqueous solution (S5). The film forming aqueous solution storing the electrons is contacted with the inner surface of the purification system piping, and Ni ions incorporated into the inner surface are reduced by the electrons, and a Ni metal film is formed on the inner surface. Platinum ions and a reducing agent are injected into the circulation piping (S9, S10), and an aqueous solution containing the platinum ions and the reducing agent is supplied to the purification system piping to deposit platinum on the surface of the Ni metal film.

Disclosed herein is a method of coating, comprising providing an article having an internal passage therein to be coated; electrolytically applying a first layer that comprises chromium or a chromium alloy onto a surface of the internal passage; electrolytically applying a second layer comprising aluminum or an aluminum alloy onto the first layer; and heat treating the article to promote interdiffusion between the first layer and the second layer.

A method is provided of forming a coating within an internal pathway. The method comprises: providing a body having an inlet and an outlet and an internal surface which defines an internal pathway extending within the body between the inlet and the outlet; streaming a mixture of a gas and a fluid along at least a part of a length of the internal pathway, the fluid comprising one or more substances for forming a solid coating on the internal surface, the fluid being a liquid solution of said one or more substances in a solvent or being a dispersion with at least one of said one or more substances being solid particles dispersed in a liquid continuous phase; during said streaming of the mixture, applying localised heat progressively along said at least a part of the length of the internal pathway. The progressive application of localised heat causes, within said at least a part of the length of the internal pathway, formation from the one or more substances of a solid coating on the internal surface.

The invention provides a heat exchange element comprising a substrate and a coating, wherein the coating is present on at least a part of a flow path defined by the heat exchange element. The coating comprises a metal and has a structure comprising spikes having a length of up to 100 m; the average length of the spikes various throughout the coating. The invention also provides a method of transferring heat to or from a fluid which comprises providing the fluid to a flow path of the heat exchange element of the invention. The invention further provides a process for producing a heat exchange element of the invention, wherein the process comprises providing an electroless deposition solution to a surface of a substrate. The invention further provides a flow process for producing a heat exchange element and a heat exchange element obtained or obtainable by that process.

Disclosed herein is a method of coating, comprising providing an article having an internal passage therein to be coated; electrolytically applying a first layer that comprises chromium or a chromium alloy onto a surface of the internal passage; electrolytically applying a second layer comprising aluminum or an aluminum alloy onto the first layer; and heat treating the article to promote interdiffusion between the first layer and the second layer.

Disclosed are methods for coating or decorating a surface of a glass sleeve. The methods include depositing a metal layer onto a surface of the glass sleeve by an electroless plating method. Also disclosed are glass sleeves which are coated or decorated on an internal surface, and electronic devices comprising the coated glass sleeves.

Method for preparing high-strength and durable super-hydrophobic film layer on inner wall of elongated metal tube includes roughening treatment of inner wall of a metal tube, electrodepositing preparation of nickel-phosphorus alloy layer and functional coating, heat treatment, subsequent anodizing and low surface energy modification. The method greatly reduces the influence of local mass transfer resistance, and a uniform nanocrystalline film layer is electroplated under the ultrasound induction. Since only electroplating solution is filled in the tube during the preparation process, the consumption of device and raw materials is greatly reduced. Also, since silica particles are added to the electroplating solution in preparing the nanocrystalline film layer, the surface morphology can be made more uniform and denser in terms of the microscopic morphology. Nano-scale channels structures are etched, so that the super-hydrophobic inner surface can have a better ability to store air, and its water flow impact resistance is greatly enhanced.

Disclosed herein is a method of coating, comprising providing an article having an internal passage therein to be coated; electrolytically applying a first layer that comprises chromium or a chromium alloy onto a surface of the internal passage; electrolytically applying a second layer comprising aluminum or an aluminum alloy onto the first layer; and heat treating the article to promote interdiffusion between the first layer and the second layer.