摘要:
A process for depositing coatings, and particularly erosion-resistant coatings suitable for protecting surfaces subjected to collisions with particles, such as a compressor blade of a gas turbine engine. The blade has an airfoil comprising oppositely-disposed convex and concave surfaces, oppositely-disposed leading and trailing edges defining therebetween a chord length of the airfoil, and a blade tip. An erosion-resistant coating is present on at least the concave surface, but not on the convex surface within at least 20% of the chord length from the leading edge.
摘要:
Erosion- and impact-resistant ceramic coatings suitable for protecting surfaces subjected to collisions with particles, including nominally round particles that typically inflict impact damage and more aggressive irregular-shaped particles that typically inflict erosion damage. The ceramic coating is formed to have one of three compositions: at least one layer of titanium aluminum nitride (TiAlN) having a thickness of about 25 to about 100 micrometers; multiple layers of chromium nitride (CrN) and TiAlN, each layer having a thickness of about 0.2 to about 1.0 micrometers to yield a total coating thickness of at least about 3 micrometers; and at least one layer of titanium silicon carbonitride (TiSiCN) having a thickness of about 15 to about 100 micrometers. The ceramic coating preferably has a total coating thickness of up to about 100 micrometers, and is deposited by a physical vapor deposition process to have a columnar and/or dense microstructure.
摘要:
Erosion- and impact-resistant ceramic coatings suitable for protecting surfaces subjected to collisions with particles, including nominally round particles that typically inflict impact damage and more aggressive irregular-shaped particles that typically inflict erosion damage. The ceramic coating is formed to have one of three compositions: at least one layer of titanium aluminum nitride (TiAlN) having a thickness of about 25 to about 100 micrometers; multiple layers of chromium nitride (CrN) and TiAlN, each layer having a thickness of about 0.2 to about 1.0 micrometers to yield a total coating thickness of at least about 3 micrometers; and at least one layer of titanium silicon carbonitride (TiSiCN) having a thickness of about 15 to about 100 micrometers. The ceramic coating preferably has a total coating thickness of up to about 100 micrometers, and is deposited by a physical vapor deposition process to have a columnar and/or dense microstructure.
摘要:
Wear-resistant coating systems suitable for protecting surfaces subjected to contact wear at high temperatures, such as surfaces of an assembly comprising high-temperature components of gas turbine engines. The components have surfaces in wear contact with each other. One of the surfaces has a wear-resistant coating system thereon so as to be in wear contact with the surface of the other component. The wear-resistant coating system contains alternating layers of TiAlN and CrN.
摘要:
Wear-resistant coating systems suitable for protecting surfaces subjected to contact wear at high temperatures, such as surfaces of an assembly comprising high-temperature components of gas turbine engines. The components have surfaces in wear contact with each other. One of the surfaces has a wear-resistant coating system thereon so as to be in wear contact with the surface of the other component. The wear-resistant coating system contains alternating layers of TiAlN and CrN.
摘要:
Zirconia-containing ceramic compositions that are capable of providing thermal barrier coatings wherein the zirconia is stabilized in the cubic crystalline phase. These compositions comprise at least about 50 mole % zirconia and a stabilizing amount up to about 49 mole % of a stabilizer component comprising: (1) a first metal oxide selected from the group consisting of ytterbia, neodymia, mixtures of ytterbia and neodymia, mixtures of ytterbia and lanthana, mixtures of neodymia and lanthana, and mixtures of ytterbia, neodymia and lanthana in an amount of from about 5 to about 49 mole % of the composition; and (2) a second metal oxide selected from the group consisting of yttria, calcia, ceria, scandia, magnesia, india and mixtures thereof in an amount of about 4 mole % or less of the composition. The ceramic composition further comprises one or more of a third metal oxide selected from the group consisting of: (a) hafnia in an amount from about 0.5 to about 40 mole % of the composition; and (b) tantala in an amount of from about 0.5 to about 10 mole % of the composition. These compositions are useful in preparing thermal barrier coatings for an underlying substrate of articles that operate at, or are exposed to, high temperatures.
摘要:
A thermal barrier coatings for the underlying substrate of articles that operate at, or are exposed to, high temperatures. The thermal barrier coating includes a zirconia-containing upper layer wherein the zirconia is stabilized in the cubic crystalline phase to reduce the thermal conductivity of the coating. The thermal barrier coating further includes a zirconia-containing lower layer stabilized in the tetragonal crystalline phase that increases the adherence of the upper layer to the bond coat layer that overlies the substrate of the article to improve the resistance of the coating to spallation.
摘要:
Zirconia-containing ceramic compositions having a c/a ratio of the zirconia lattice in the range of from about 1.005 to about 1.016. These compositions comprise a stabilizing amount up to about 10 mole % of the composition of a stabilizer component which comprises: (1) a first metal oxide selected from the group consisting of yttria, calcia, ceria, scandia, magnesia, india and mixtures thereof in an amount of from about 1.5 to about 6 mole % of the composition of; (2) a second metal oxide selected from the group consisting of lanthana, neodymia and mixtures thereof in an amount of from about 0.5 to about 4 mole % of the composition; and (3) optionally ytterbia in an amount of from about 0.5 to about 4 mole % of the composition. These compositions further comprise hafnia in an amount of from about 0.5 to about 15 mole % of the composition; and optionally tantala in an amount of from about 0.5 to about 1.5 mole % of the composition. These compositions are useful in preparing thermal barrier coatings having a balance of reduced thermal conductivity with good producibility, spallation resistance and erosion/impact resistance for an underlying substrate of articles that operate at, or are exposed to, high temperatures.
摘要:
A bushing includes a bronze backing layer having a first axial end, a second axial end, and a central opening, the bushing having a cylindrical shape and a porous bronze layer. PTFE or other suitable low friction material is impregnated into the porous bronze layer at one of a radially inner or outer surface of the bushing. A PTFE or other suitable low friction material topical layer is disposed adjacent the impregnated layer. The bushing may optionally comprise a flange which also includes the bronze backing layer, the porous bronze and impregnated layer, and the topical layer on an axially inner or outer surface.
摘要:
An apparatus for providing a vacuum coating to a workpiece, including: a coating chamber containing a coating material, with the coating chamber being operable at an elevated temperature and a sub-atmospheric pressure; an electron beam gun projecting an electron beam into the coating chamber and onto the coating material, where the electron beam gun is operable to melt the coating material and to evaporate molten coating material; and, a mechanism for supporting manipulating the workpiece in the coating chamber. The supporting mechanism further includes: a coupling device for retaining the workpiece; a joint connected to the coupling device enabling movement of the workpiece in all directions; an intermediate member connecting the coupling device and the joint; and, a device connected to the intermediate member for moving the workpiece in a designated vertical plane. The supporting mechanism may also include a device connected to the intermediate member for moving the workpiece in a designated horizontal plane.