US 12,116,903 B2
Composite airfoils with frangible tips
Nitesh Jain, Bangalore (IN); Nicholas Joseph Kray, Mason, OH (US); Daniel Edward Mollmann, Cincinnati, OH (US); and David William Crall, Loveland, OH (US)
Assigned to General Electric Company, Evendale, OH (US)
Filed by General Electric Company, Schenectady, NY (US)
Filed on Jun. 30, 2021, as Appl. No. 17/363,102.
Prior Publication US 2023/0003129 A1, Jan. 5, 2023
Int. Cl. F01D 5/14 (2006.01); F01D 5/28 (2006.01); F01D 21/04 (2006.01)
CPC F01D 5/147 (2013.01) [F01D 5/282 (2013.01); F01D 5/284 (2013.01); F01D 21/045 (2013.01); F05D 2220/36 (2013.01); F05D 2240/304 (2013.01); F05D 2240/307 (2013.01); F05D 2300/6033 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A composite airfoil of a gas turbine engine, comprising:
opposite pressure and suction sides extending radially along a span from a root to a tip, the root defining a first radial extremity of the airfoil and the tip defining a second radial extremity of the airfoil;
a body section extending radially along the span;
a tip section extending radially along the span, the tip section including the tip; and
a metallic tip cap extending to a trailing edge of the tip and applied over the tip,
wherein the composite airfoil is formed from a composite material comprising fibers disposed in a matrix material, the composite material in the body section having a body fiber volume and the composite material in the tip section having a tip fiber volume, and
wherein the body fiber volume is greater than the tip fiber volume such that the tip section and the metallic tip cap are configured to fracture under a tip fracture load,
wherein the metallic tip cap comprises a first breakaway feature such that the metallic tip cap is configured to fracture under the tip fracture load, and
wherein the first breakaway feature is a tapered thickness pressure side wall and a tapered thickness suction side wall, the pressure side wall of the metallic tip cap extending along the pressure side of the composite airfoil at the tip, the suction side wall of the metallic tip cap extending along the suction side of the composite airfoil at the tip.