Provided is a method for corrosion protection in bolt holes of a wind turbine, whereby a sleeve made of a corrosion resistant metallic material is inserted into the bolt hole, in particular covering the whole length of the bolt hole wall, and at least partly expanded using an expander tool to be fixed in the bolt hole.

An airfoil is disclosed. The airfoil may comprise a leading edge, a body portion and a trailing edge formed from a high-modulus plating. The body portion of the airfoil may be formed from a material having a lower elastic modulus than the high-modulus plating. The high-modulus plating may improve the stiffness of the trailing edge, allowing for thinner trailing edges with improved fatigue life to be formed.

A composite component and a plated polymer component are disclosed. The composite component may comprise a body portion formed from an organic matrix composite, a first metal coating applied to a surface of the body portion, and an outer metal layer on the first metal coating that is erosion-resistant. The plated polymer component may comprise a polymer substrate, a metal plating layer applied to a surface of the polymer substrate, and at least one selectively thickened region in the metal plating layer. The at least one selectively thickened region may assist in protecting the plated polymer component against wear and/or erosion.

An engine turning clock work motor including two shape memory alloy (SMA) torque tube actuators, ratcheting mechanisms, and gearing. The gearing communicates the SMA torque tube actuators with a common gear that applies torque to a shaft, so that while one torque tube is heated and applying torque, the other torque tube is relaxed (using a cooling mechanism). The ratchet prevents the relaxing torque tube from applying torque in the incorrect direction.

A blade for a gas turbine engine. The blade having: an airfoil formed from a first material; a protective sheath disposed on a leading edge of the airfoil, the protective sheath being formed from a second material, the first material being galvanically incompatible with the second material and the first material being less noble than the second material; a non-conductive material disposed between the protective sheath and the airfoil so that they are electrically isolated from each other; a sacrificial anode in contact with the blade, wherein the sacrificial anode is formed from a third material that is less noble than the first material such that it will corrode before the first material if the non-conductive material disposed between the protective sheath and the airfoil is compromised and the first material and the second material are no longer electrically isolated from each other.

An abradable powder composition is includes a metal component, a lubricant component, and a polymer component. A portion of the metal component is wrapped in the lubricant component to achieve high lubricity and abradability. The abradable powder composition can be used to form an abradable seal coating provided for use in a turbo machinery having a housing and a wheel having multiple blades. The housing houses the wheel which rotates therein. The seal coating is formed on the inner walls of housing adjacent where the wheel blades pass during their rotation. When the wheel is rotated such that, the blades contact the seal coating, it is abraded to form a close fit gap. The abradable seal coating preferably does not produce significant wear of the blade tips or transfer abradable material significantly to the blade tips upon being abraded.