Alstom Technology Limited

Alstom (switzerland) Ltd

Alexander Schnell

Matthias Hoebel

Maxim Konter

Klaus Germerdonk

Giampiero Antonelli

Cyrille Bezencon

Abdus Suttar Khan

Wilfried Kurz

Walter Brehm

Edward Obbard

Mohamed Youssef Nazmy

Bruno Schuermans

Hans-Peter Bossmann

John Fernihough

Alexander Stankowski

Nicolas Noiray

Andreas Boegli

Felix Michael Reinert

Diane Lauffer

Nigel Anthony Rhodes

Christoph Toennes

Günter Ambrosy

Simone Hövel

Hans Bissig

Matthias Höbel

Yves Pellaton

Rainer Kurtz

Joachim Roesler

A combustion device for a gas turbine that includes a portion having first and second walls that defines an inside of the combustion device, a zone between the first and second walls and an outside of the combustion device. A plurality of first passages connect the inside of the combustion device to the zone between the first and second walls and a plurality of second passages connect the zone between the first and second walls to the outside of the combustion device. A plurality of chambers are defined within the zone between the first and second walls, each chamber being connected with one first passage and at least one second passage. Each chamber defining a Helmholtz damper.

Combustion device of a gas turbine including a plurality of passages and chambers defining helmholtz resonators

A turbine blade for a turbine rotor, is provided having a single-crystal basic body which has a blade tip and extends in the radial direction. The turbine blade includes at least one oxidation-resistant intermediate coating, which is applied by laser metal forming and is epitaxially bonded to the basic body, is arranged on the radially outer blade tip, and in that an at least single-layer, wear-resistant and oxidation-resistant coating, which is applied by laser metal forming and consists of oxidation-resistant binder material and abrasive particles embedded therein, is arranged on at least certain regions of said epitaxial intermediate coating.

Abrasive single-crystal turbine blade

A dual brazing alloy element for a materially integral connection of a ceramic surface to a metallic surface includes a first layer having a Ni-based brazing alloy with a Ni content of at least 50% by weight and having at least one component configured to lower a melting point of the Ni-based brazing alloy selected from the group consisting of Si, B, Mn, Sn and Ge. A second layer includes an active brazing alloy material having a total content of 1-15% by weight of at least one active element selected from the group consisting of Ti, Hf, Zr and V.

Dual brazing alloy element, process for producing it and uses thereof

A leaf seal for sealing a shaft rotating about an axis, in particular in a gas turbine, includes a plurality of spaced-apart leaves arranged in a concentric circle around the axis and fixed in position by brazing, the leaves having surfaces oriented essentially parallel to the axis. The leaves are brazed to one another via intermediate spacers made of a brazing foil, so that a brazed joint is produced by brazing alloy from the brazing foils. The brazing temperature may be set to an optimum value just above the solidus temperature of the brazing foil, at which partial melting of the brazing foil occurs and penetration of liquid brazing alloy into the gap between the leaves is avoided.

Leaf seal, in particular for a gas turbine, and method of producing it

A gas turbine engine hot gas component repair method for defects that do not extend through the thickness of the component is provided. First defects are removed by machining a cavity in the surface of a component. Coupons, fittable within the cavities are manufactured, are for example coated with brazing medium on an inner surface and then joined to the component by joining means such as laser metal forming. The joint holds the coupon during later heat treatment, thereby eliminating a need for holding aids. Before heat treatment, a further brazing medium can be applied to the surface of the coupon overlapping onto the component. A single heat treatment, brazing the coupon to the component and, brazing the brazing medium to the outer surface of the coupon can, then be used to complete the repair.

Gas turbine hot gas component repair method

It is disclosed a method of applying a coating () with a controlled laser metal forming process. A light source with a specific power and a signal capturing apparatus is moved over an article () to form locally a melt pool () on the surface () of the article () to which a coating powder () is injected. An optical signal () is captured from the melt pool (), and the monitored optical signal () is used for the determination of the temperature and temperature fluctuations of the melt pool (). Furthermore, a control system () is used to adjust at least one process parameter such as the power of the light source to obtain desired melt pool properties. Subsequently the melt pool () solidifies. The high degree of control over the microstructure provides an efficient tool for generating laser metal formed hard coatings () with optimised wear properties.

Method for controlling the microstructure of a laser metal formed hard layer

It is disclosed a method of measuring the thickness and/or the depletion of Al and Cr of a &#x3b3;/&#x3b3;' MCrAlY-coating after the use in a high temperature environment, the &#x3b3;/&#x3b3; MCrAlY-coating exhibiting a non-equilibrium &#x3b3;/&#x3b3;&#x2032;-microstructure at a temperature lower than the temperature during operation. Before the coating conductivity by means of a multifrequency eddy current system is measured a heat treatment is applied to transform the non-equilibrium &#x3b3;/&#x3b3;&#x2032;-microstructure to a equilibrium microstructure having a &#x3b1;-Cr phase. Subsequently the Al and/or Cr depletion of the coating from the coating conductivity and permeability is determined.

Non-destructive testing method of determining the depletion of a coating

It is disclosed a method of determining the exposure temperature of Al and Cr of a &#x3b3;/&#x3b3;' MCrAlY-coating after the use in a high temperature environment, the &#x3b3;/&#x3b3;&#x2032; MCrAlY-coating exhibiting a non-equilibrium &#x3b3;/&#x3b3;&#x2032;-microstructure at a temperature lower than the temperature during operation and the depletion of chromium from the &#x3b3;/&#x3b3;&#x2032;-MCrAlY-coating still allows the &#x3b1;-Cr phase to form. The coating conductivity and permeability by means of a multifrequency eddy current system is measured at different locations of the component and from the measured conductivity and permeability the exposure temperature of said different locations of the components is determined.

Non-destructive testing method of determining the service metal temperature of a component

A gas turbine component consists of a superalloy base material with a single crystal structure and a protective MCrAlY-coating (). The MCrAlY-coating () has a g/g' single crystal structure, which is epitaxial with the base material. It has be determined the critical factors for the successful epitaxial and crack-free growth of the MCrAlY-coating ().

MCrAlY-coating

In a heat treatment process for a single-crystal or directionally solidified material body comprising a nickel-based superalloy, the material body is solution-annealed and then at a first temperature &#x3b3;' particles of greater than 1 &#x3bc;m are precipitated in a proportion by volume with V&#x2212;Vof less than 50%, where Vis the total amount of &#x3b3;&#x2032; particles after complete heat treatment and Vis the proportion of the &#x3b3;&#x2032; particles which is greater than 1 &#x3bc;m, and at least at a second temperature '&#x3b3;' particles of less than 1 &#x3bc;m are precipitated. The &#x3b3;&#x2032; particles are preferably precipitated in a size of 2 pin or more with a proportion by volume of 0.25&#x3c;(V&#x2212;V)/(100&#x2212;V)&#x3c;0.55 at the first temperature. The proportion by volume Vof the &#x3b3;&#x2032; particles will be at least 50%.

Heat treatment method for bodies that comprise a nickel based superalloy

A gas turbine component consists of a superalloy base material with a single crystal structure and a protective MCrAlY-coating. The MCrAlY-coating the MCrAlY has a &#x3b3;/&#x3b2;-phase and single crystal structure, which is epitaxial with the base material.

Method of growing a MCrAlY-coating and an article coated with the MCrAlY-coating

It is disclosed a method of detecting and quantifying subsurface defects () in an article () made of high strength non magnetisable materials after the use in a high temperature environment. A crack () or gap on a surface () of the article () is brazed and after the brazing operation the crack () or any remaining braze defect or subsurface crack () is detected and quantified by means of a multifrequency eddy current system.

Non-destructive method of detecting defects in braze-repaired cracks

It is disclosed a method for fabricating, modifying or repairing of single crystal or directionally solidified articles. Two single crystal or directionally solidified prefabricated parts are joint by isothermally brazing using a brazing material. After that an epitaxial or non-epitaxial layer on the surface of the created article and of the braze joint is applied using a laser metal forming process.

Method for fabricating, modifying or repairing of single crystal or directionally solidified articles

A process of brazing cracks and gaps in a single crystal article which takes places isothermally under the following conditions: the temperature of the isothermal solidification is between T &plus;5*(wt-%B ) and (T &minus;70*(wt-%B )), while (wt-%B*wt-%Cr) is between 15 and 40 and (T &minus;T ) is above 140&deg; C. This results in an homogeneous &ggr;/&ggr;&prime;-microstructure of the isothermal solidified, brazed joint with mechanical properties similar to those of the base material.

Growing community of inventors

Ennetbaden, Switzerland

Alexander Schnell