A turbomachine includes a shroud and a rotor, which includes first and second blades. A first blade tip and a second blade tip respectively include a base and a first layer. The second blade tip also includes an abrasive second layer layered over the respective first layer. The first layer has a lower material hardness than the shroud. The second layer has a lower thermal stability than the shroud and the first layer. The rotor performs a grind operation and, subsequently, a post-grind operation. The second layer, in the grind operation, contacts and removes material from the shroud, and wears away, thereby revealing the first layer of the second blade tip for the post-grind operation. The first layer of the first blade tip is spaced apart with at least some radial clearance from the shroud in the grind and post-grind operations.

The disclosure relates to turbomachine components which include one or more coating-capturing features for thermal insulation. A turbomachine component may include: a body having an exterior surface positioned within a hot gas path (HGP) section of a turbomachine; and a coating-capturing feature mounted on the exterior surface of the body and in thermal communication with the HGP section of the turbomachine, wherein the coating-capturing feature comprises: a first member positioned on the exterior surface of the body, the first member having at least one outer sidewall defining a first perimeter of the coating-capturing feature, a second member positioned on the first member and having at least one outer sidewall defining a second perimeter of the coating-capturing feature, wherein the first member separates the second member from the exterior surface of the body, and an indentation positioned between the first and second members.

An inner coating layer for solid-propellant rocket engines, constituted by a material comprising from 45% to 55% wt. of a a cross-linkable, unsaturated-chain polymer base, from 11% to 13% wt. of silica, from 15% to 25% wt. of vulcanizing agents and plasticizers, from 5% to 7% wt. of aramid fiber and from 10% to 15% wt. of microspheres made of a material selected among glass, quartz and nano clay, having diameter lower than 200 gm, density comprised between 0.30 and 0.34 g/cc and resistance to hydrostatic pressure greater than, or equal to, 4500 psi.

In one aspect, the present disclosure is directed to a gas turbine sealing assembly that includes a first static gas turbine wall and a second static gas turbine wall. A seal is disposed between the first static gas turbine wall and the second static gas turbine wall. The seal includes a shield wall constructed from a first material that includes a first shield wall portion and a second shield wall portion. A spring constructed from a second material includes a first spring portion and a second spring portion. The first shield wall portion is adjacent to the first spring portion, and the second shield wall portion is adjacent to the second spring portion.

A drag pump for pumping gas and a set of vacuum pumps including the drag pump are disclosed. The drag pump comprises: a rotor configured to rotate within a stator component and to drive a gas to be pumped from a gas inlet to a gas outlet; magnetic bearings for rotatably mounting the rotor within the pump; wherein at least a portion of the rotor and stator component configured to contact the gas to be pumped are configured for operation at temperatures above 130 C.

A method for forming a coating system on a component includes depositing a reactive layer with predetermined CMAS reaction kinetics on at least a portion of a thermal barrier coating. The method also includes activating the reactive layer with a scanning laser. A component, such as a gas turbine engine component, includes a substrate, a thermal barrier coating and a reactive layer. The thermal barrier coating is deposited on at least a portion of the substrate. The reactive layer is deposited on at least a portion of the thermal barrier coating. The reactive layer has predetermined CMAS reaction kinetics activated by laser scanning.

An article for high temperature service is presented. The article includes a substrate and a plurality of coatings disposed on the substrate. At least one coating in the plurality of coatings includes an oxide of nominal composition A.sub.xB.sub.1-yD.sub.yO.sub.z, wherein A includes a rare-earth element, B includes tantalum or niobium, D includes zirconium or hafnium, 2x3, 0<y<1, and 6z7.

A process for manufacturing a preformed sheet having geometric surface features for a geometrically segmented abradable ceramic thermal barrier coating on a turbine engine component, the process comprising the steps of providing a preformed sheet material. The process includes forming a partially of geometric surface features in the sheet material. The process includes joining the sheet material to a substrate of the turbine engine component. The process includes disposing a thermally insulating topcoat over the geometric surface features and forming segmented portions that are separated by faults extending through the thermally insulating topcoat from the geometric surface features.

An additively manufactured thermally insulating structure comprising a base layer and a fire-resistant layer adjacent to the base layer that forms an air gap therebetween. A method for assembling a miniature gas turbine engine includes additively manufacturing an additively manufactured thermally insulating structure onto a static structure of the miniature gas turbine engine.

A method for forming a coating system on a component includes depositing a reactive layer with predetermined CMAS reaction kinetics on at least a portion of a thermal barrier coating. The method also includes activating the reactive layer with a scanning laser. A component, such as a gas turbine engine component, includes a substrate, a thermal barrier coating and a reactive layer. The thermal barrier coating is deposited on at least a portion of the substrate. The reactive layer is deposited on at least a portion of the thermal barrier coating. The reactive layer has predetermined CMAS reaction kinetics activated by laser scanning.