Abstract: A method of forming a protective coating. The method includes providing a substrate including at least one chemical element and a surface; forming a basecoat composition including an aluminium phase including aluminium; applying the basecoat composition on the surface of the substrate to form a basecoat layer; heating the basecoat layer to a first temperature for a predetermined period of time; applying a glow discharge plasma on the basecoat layer; and heating the basecoat layer to a second temperature greater than the first temperature, in order to activate an exothermic reaction between at least the aluminium phase of the basecoat layer and the at least one chemical element of the substrate, wherein the exothermic reaction forms the protective coating on the surface of the substrate.

Abstract: A coated substrate comprising a metal or metal alloy such as a high speed steel, TiAl based alloy or Ni based alloy or an electrically conductive ceramic material, wherein the coating comprises a hard material protective coating comprising alternating layers of different compositions, wherein a first composition of the alternating layers comprises silicon, Si, and/or a second composition of the alternating layers comprises boron, B.

Abstract: A coated substrate comprising a metal or metal alloy such as a high speed steel, TiAl based alloy or Ni based alloy or an electrically conductive ceramic material, wherein the coating comprises a hard material protective coating comprising alternating layers of different compositions, wherein a first composition of the alternating layers comprises silicon, Si, and/or a second composition of the alternating layers comprises boron, B.

Abstract: The present invention provides for an etch and mar resistant low VOC clear coating composition most suitable for use as a top clear coat in multi-layered OEM or refinish automotive coatings. The coating composition includes isocyanate, carbonate and melamine components. The isocyanate component includes an aliphatic polyisocyanate. The composition may be formulated as a two-pack or one-pack coating composition, wherein the isocyanate functionalities are blocked with a blocker such as a mono-alcohol.

Abstract: A multi-layer thermal barrier coating for a superalloy article includes a metallic matrix coating containing particles, a MCrAlY alloy bond coating on the metallic matrix coating, a thin oxide layer on the MCrAlY alloy bond coating and a columnar grain ceramic thermal barrier coating. The metallic matrix coating includes a 80 wt % nickel-20 wt % chromium alloy. The particles include metallic compounds such as carbides, oxides, borides and nitrides, which react with harmful transition metal elements such as titanium, tantalum and hafnium, in the superalloy substrate. One suitable compound is chromium carbide because the hafnium transition metal elements will take part in an exchange reaction with the chromium in the chromium carbide to form a stable carbide of the harmful transition metal element. This reduces the amount of harmful elements in the superalloy reaching the oxide layer and increases the service life of the thermal barrier coating.

Abstract: A metallic article (30) comprises a bond coating (34) on the metallic article (30) and a ceramic thermal barrier coating (38) on the bond coating (34). The ceramic thermal barrier coating (38) comprises a plurality of columnar grains (40) extending substantially perpendicular to the surface of the metallic article (30). The ceramic thermal barrier coating (38) has an inner portion (44), a transition portion (46) and an outer portion (48). Each columnar grain (40) has a substantially constant cross-sectional area throughout its length in the outer portion (48), has smooth surfaces and there are distinct uniform gaps (42) between columnar grains to minimize the stress/strain in the columnar grains (40) and/or to minimize the stress/strain between adjacent columnar grains (40) and thereby increases the resistance to spallation of the ceramic thermal barrier coating. The columnar grains (40) are produced by controlling the evaporation rate of the ceramic, the temperature and speed of rotation of the article (30).

Abstract: A multi-layer thermal barrier coating for a superalloy article includes a metallic matrix coating containing particles, a MCrAlY alloy bond coating on the metallic matrix coating, a thin oxide layer on the MCrAlY alloy bond coating and a columnar grain ceramic thermal barrier coating. The metallic matrix coating includes a 80 wt % nickel-20 wt % chromium alloy. The particles include metallic compounds such as carbides, oxides, borides and nitrides, which react with harmful transition metal elements such as titanium, tantalum and hafnium, in the superalloy substrate. One suitable compound is chromium carbide because the harmful transition metal elements will take part in an exchange reaction with the chromium in the chromium carbide to form a stable carbide of the harmful transition metal element. This reduces the amount of harmful elements in the superalloy reaching the oxide layer and increases the service life of the thermal barrier coating.

Abstract: A metallic article includes a bond coating and a ceramic thermal barrier coating on the bond coating. The ceramic thermal barrier coating includes a plurality of columnar grains, which extend perpendicularly to the surface of the metallic article. Each columnar grain includes a plurality of layers. Some of the layers include sub-grains extending at an acute angle to the surface of the metallic article to form voids between adjacent sub-grains. The voids are arranged at an acute angle to the surface of the metallic article and reduce the thermal conductivity of the ceramic thermal barrier coating. Some of the layers include sub-grains extending perpendicularly to the surface of the metallic article to provide erosion resistance.

Abstract: A method of applying a coating to a metallic article (10) comprises placing the metallic article within a hollow cathode (38) in a vacuum chamber (30), evacuating the vacuum chamber (30), applying a negative voltage to the hollow cathode (38) to produce a plasma and such that the material of the hollow cathode (38) is sputtered onto the metallic article (10) to produce a coating (22). A positive voltage (V1) is applied to the metallic article (10) to attract electrons from the plasma to heat the coating (22) and so inter-diffuse the elements of the metallic article (10) and the protective coating (22) and a negative voltage (V2) is applied to the metallic article (10) to attract ions from the plasma to bombard the coating (22) to minimize defects in the coating (22).

Abstract: A metallic article includes a bond coating and a ceramic thermal barrier coating on the bond coating. The ceramic thermal barrier coating includes a plurality of columnar grains extending substantially perpendicularly to the surface of the metallic article. Each columnar gain has a plurality of first layers, a plurality of second layers and a plurality of third layers. The first layers have a different structure from the second layers and the third layers. The second layers have a different structure from the third layers. The first layers have the same composition as the third layers. The second layers have a greater proportion of voids than the first layers and the third layers. The voids reduce the thermal conductivity of the thermal barrier coating. The second layers may also have a different composition from the first layers and the third layers to reduce the thermal conductivity.

Abstract: A metallic article (10) comprises a bond coating (14,16) on the metallic article (10) and a ceramic thermal barrier coating (18) on the bond coating (14,16). The ceramic thermal barrier (18) coating comprises zirconia stabilized with yttria, calcia, magnesia or india, and erbia to reduce the thermal conductivity of the ceramic thermal barrier coating (18). The ceramic thermal barrier coating (18) is at least 100 microns thick. The erbium atom has an atomic mass greater than the average atomic mass of the zirconium, the yttrium, calcium, magnesium or indium and the oxygen atoms to reduce phonon thermal conductivity of the ceramic thermal barrier coating (18). The ceramic thermal barrier coating (18) comprises 4 to 20 wt % of yttria, 5 to 25 wt % of erbia and the balance is zirconia plus incidental impurities. The erbia absorbs energy in the 0.3 microns to 5 microns waveband to reduce photon thermal conductivity.

Abstract: A ceramic thermal barrier coating layer for a superalloy article is caused to adhere to the superalloy article by applying platinum to the superalloy article and heat treating at a temperature of 1100.degree. C. to 1200.degree. C. for one hour. This causes aluminum to diffuse from the superalloy article into the platinum to form a platinum enriched outer layer which generally includes a platinum enriched gamma phase and a platinum enriched gamma prime phase. An alumina layer is formed between the platinum enriched outer layer and a ceramic coating. The platinum enriched gamma phase and the platinum enriched gamma prime phase in the outer layer reduces the migration of transition metal elements to the ceramic coating to enable a very pure alumina layer to be formed.

Abstract: A multiple layer erosion resistant coating on a substrate comprises alternate layers of tungsten and titanium diboride. All of the layers have the same thickness and preferably have thickness's of between 0.3 and 1 micrometer to give improved erosion resistance. The layers are produced by spattering.

Abstract: A multi-layer thermal barrier coating (42) for a superalloy article (40) comprises a platinum enriched superalloy layer (44), an MCrAlY bond coating (46) on the platinum enriched superalloy layer (44), a platinum enriched MCrAlY layer (48) on the MCrAlY bond coating (46), a platinum aluminide coating (50) on the platinum enriched MCrAlY layer (48), an oxide layer (54) on the platinum aluminide coating (50) and a ceramic thermal barrier coating (56) on the oxide layer (54). The platinum aluminide coating (50) and the platinum enriched MCrAlY layer (48) reduce movement of transition metals from the superalloy substrate (40) and the MCrAlY bond coating (46) to the oxide layer (54) so that the oxide layer is very pure alumina.

Abstract: A multiple layer erosion resistant coating on a substrate comprises alternate layers of tungsten and titanium diboride. All of the layers have the same thickness and preferably have thickness's of between 0.3 and 1 micrometer to give improved erosion resistance. The layers are produced by sputtering.

Abstract: A coated article includes a superalloy substrate, an intermediate bond coat and a thermal barrier coating. The bond coat may include a platinum aluminide layer underlying a thin oxide layer. The thin oxide layer may include alumina. The coated article has high strength and durability at high temperatures over extended periods of time and thus is especially useful in the form of, e.g., a turbine blade or turbine vane.

Abstract: A ceramic thermal barrier coating layer for a superalloy article is caused to adhere to the superalloy article by applying platinum to the superalloy article and heat treating at a temperature of 1100.degree. C. to 1200.degree. C. for one hour. This causes aluminum to diffuse from the superalloy article into the platinum to form a platinum enriched outer layer which generally includes a platinum enriched gamma phase and a platinum enriched gamma prime phase. An alumina layer is formed between the platinum enriched outer layer and a ceramic coating. The platinum enriched gamma phase and the platinum enriched gamma prime phase in the outer layer reduces the migration of transition metal elements to the ceramic coating to enable a very pure alumina layer to be formed.

Abstract: A vacuum chamber is provided with a pair of seals to enable a fibre to be continuously supplied into and removed from the vacuum chamber for application of a coating. The seals comprise a first chamber which is supplied with argon and a second chamber which is evacuated by a pump. The first chamber is connected to atmosphere by a first hypodermic tube, the first chamber is connected to the second chamber by a second hypodermic tube and the second chamber is connected to the interior of the vacuum chamber by a third hypodermic tube. The hypodermic tubes are coaxial and are telescoped together. The fibre is arranged to pass sequentially through the hypodermic tubes into the vacuum chamber. The argon supplied to the first chamber reduces the air flow down the hypodermic tubes. The seal maintains the pressure in the vacuum chamber and does not contaminate the fibre.

Abstract: A multiple layer erosion resistant coating on a substrate comprises alternate layers of tungsten and titanium diboride. All of the layers have the same thickness and preferably have thickness's of between 0.3 and 1 micrometer to give improved erosion resistance. The layers are produced by sputtering.

Abstract: A coated article includes a superalloy substrate, an intermediate bond coat and a thermal barrier coating. The bond coat may include a platinum aluminide layer underlying a thin oxide layer. The thin oxide layer may include alumina. The coated article has high strength and durability at high temperatures over extended periods of time and thus is especially useful in the form of, e.g., a turbine blade or turbine vane.