A method of joining a first work piece and a second workpiece. The first and second workpieces may be rotor wheels of a rotor for a turbomachine. At least one of the workpieces includes an oxide dispersion strengthened alloy material and the first and second work pieces may be joined by welding a cladding on at least one of the workpieces to the other of the workpieces, without welding a substrate of the at least one workpiece which includes an oxide dispersion strengthened alloy material.

A method for implementing an abradable coating comprising: a pattern-forming step in which, using a slurry containing ceramic particles and solvent, a slurry pattern is formed on the surface of a thermal barrier coating layer; and a firing step in which the slurry pattern formed on the surface of the thermal barrier coating layer is fired to form an abradable coating layer. A ceramic material included in the thermal barrier coating layer and ceramic particles included in the abradable coating layer are of the same type.

The present disclosure relates generally to blades used in gas turbine engines. More specifically designs in accordance with the present disclosure include turbine blades comprising ceramic matrix composite materials with abrasive tips coupled thereto.

A rotor for a turbomachine is provided which includes a hub; and a plurality of blades extending radially from the hub, the plurality of blades comprising a first subset of blades having first tips and an abrasive coating on the first tips, and a second subset of blades having second tips with no abrasive coating on the second tips, wherein a radius (R.sub.2) of the first subset of blades, including thickness of the abrasive coating, is greater than a radius (R.sub.1) of the second subset of blades, and wherein a base radius (R) of the first subset of blades, not including thickness of the abrasive coating, is less than the radius (R.sub.1) of the second subset of blades.

An additively manufactured alloy component has a first portion formed of the alloy and having a first grain size, and a second portion formed of the alloy and having a second grain size smaller than the first grain size. In an embodiment, the alloy component is an alloy turbine disk, the first portion is a rim region of the alloy turbine disk, and the second portion is a hub region of the alloy turbine disk. The first and second grain sizes may be achieved by controllably varying the laser power and/or scan speed during additive manufacturing.

Disclosed herein is an article comprising a substrate; an abrasive coating disposed on the substrate; where the abrasive coating comprises a matrix having abrasive grit particles dispersed therein; and a layer of material disposed on the abrasive coating; where the layer of material is a titanium nitride (TiN), boron nitride (BN), titanium-aluminum-nitrides [(TiAl)N], titanium-aluminum-silicon-nitrides [(TiAlSi)N], chromium nitrides (CrN), aluminum oxide (Al.sub.2O.sub.3), titanium oxide (TiO.sub.2), silicon carbo-nitride (SiCN), titanium carbo-nitride (TiCN), or a combination thereof.

A method of manufacturing a net shaped seal comprising depositing a first layer of powder material on a substrate; the powder material comprising an abradable feedstock material comprising matrix alloy clad filler particles, wherein the matrix alloy cladding includes Al, Cu, Ni, Co, Cr, Fe, Si and Y; guiding a heat source over the powder material layer; laser sintering the powder material, the matrix alloy clad filler particles sinter in the absence of the filler particles melting; depositing a second layer of powder material over the first layer; laser sintering the second layer of powder material with a second laser pass at predetermined locations; wherein at least one of the matrix alloy clad filler particles sinter, and in the absence of the filler particles melting; and repeating the depositing step and laser sintering step to form subsequent layers to form an abradable seal on the substrate.

Provided are a coating structure, a turbine part having the same, and a method for manufacturing the coating structure. The coating structure is provided on a surface of a base portion including a ceramic matrix composite. The coating structure is layered on the surface of the base portion, and includes a bond coat layer formed of a rare-earth silicate and a top coat layer layered on the bond coat layer. The residual stress present in the bond coat layer is compressive residual stress. The oxygen permeability coefficient of the bond coat layer is no greater than 10.sup.9 kg.Math.m.sup.1.Math.s.sup.1 at a temperature of not lower than 1200 C. and a higher oxygen partial pressure of not less than 0.02 MPa. The bond coat layer may contain carbonitride particles or carbonitride whiskers.

In one aspect, a calcium-magnesium alumino-silicate (CMAS)-resistant coating includes an outer coating having a plurality of columnar structures formed during material deposition due to preferential material accumulation and a plurality of generally vertically-oriented gaps separating adjacent columnar structures. The columnar structures include a plurality of randomly-oriented particle splats and a CMAS-reactive material and have a total porosity of less than five percent. The plurality of generally vertically-oriented gaps extend from an outermost surface of the outer coating to a first depth of the outer coating equal to or less than a total thickness of the outer coating. The vertically-oriented gaps have a median gap width of less than five micrometers.

A weld clad layer having a substantially equiaxed grain microstructure may be formed by forming a repair area in a substrate, depositing a first layer of laser deposition spots in the repair area, and depositing a second layer of laser deposition spots over the first layer of laser deposition spots. The first layer of laser deposition spots may comprise a first laser deposition spot and a second laser deposition spot adjacent to the first laser deposition spot. The first laser deposition spot may solidify prior to deposition of the second laser deposition spot. The first layer of laser deposition spots may comprise titanium or titanium alloy.