摘要:
A method of manufacturing a substrate (16) with a ceramic thermal barrier coating (28, 32). The interface between layers of the coating contains an engineered surface roughness (12, 24) to enhance the mechanical integrity of the bond there between. The surface roughness is formed in a surface of a mold (10,20) and is infused by a subsequently cast layer of material (16, 28). The substrate may be partially sintered (76) prior to application of the coating layer(s) and the coated substrate and coating layer(s) may be co-sintered to form a fully coherent strain-free interlayer.
摘要:
A method of processing solid core ceramic matrix composite articles. The method improves the physical characteristics of the article by forming the airfoil using a co-processing method wherein a refractory ceramic is cast against a preformed ceramic matrix composite (CMC) shell. In one aspect, the shell is continuous to help prevent delaminations. In another aspect, the shell is open. In one embodiment, the article includes a split line. The split line helps the article to be less susceptible to damage caused from internal strain.
摘要:
A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.
摘要:
A method of manufacturing a component, including providing a three-dimensional computer model of the component to be produced; deconstructing the three-dimensional computer model by defining a plurality of model slices; forming a plurality of metallic foils, where each foil corresponds to a specific model slice; assembling the plurality of formed foils in a tool to form a three-dimensional component stack; and bonding the three-dimensional component stack to form the component. Characteristics of the foils may differ in various portions of the stack, such as being a different material, having a different thickness, or having a different grain orientation. The control of dimensional tolerances of internal structures, such as cooling passages, in three dimensions is devolved into two separate steps of 1) selecting a thickness of each slice/foil, and 2) controlling in two dimensions a material removal process applied to the respective foil.
摘要:
A ceramic matrix composite (CMC) structure 12 includes a plurality of layers (e.g., 16, 18, 20) of ceramic fibers. The CMC structure 12 further includes a plurality of spaced apart objects 22 on at least some of the plurality of layers along a thickness of the composite structure. The inclusion of the objects introduces an out-of-plane fiber displacement arranged to increase an interlaminar shear strength of the structure.
摘要:
Methodology and tooling arrangements for increasing interlaminar shear strength in a ceramic matrix composite (CMC) structure are provided. The CMC structure may be formed by a plurality of layers of ceramic fibers disposed between a top surface and a bottom surface of the composite structure. A plurality of surface recesses are formed on the surfaces of the structure. For example, each of the surfaces of the composite structure may be urged against corresponding top and bottom surfaces of a tool having a plurality of asperities. The plurality of surface recesses causes an out-of-plane sub-surface fiber displacement along an entire thickness of the structure, and the sub-surface fiber displacement is arranged to increase an interlaminar shear strength of the structure.
摘要:
The interlocking of two or more sections via the insertion of one or more out-of-plane features in one section or combination of sections through a void in one or more a complementary sections can result in a reinforced ceramic matrix composite article upon securing of the sections. The sections can be secured by friction between two tightly matched sections or by the use of a pin, hook, or clamp. The sections can be constructed from one or more CMC laminate sheets. The out-of-plane feature can be a loop or a flange and the void can be an orifice or a matched loop in the complementary sheet. The securing of the sections can result in a CMC article where the delamination between sheets is inhibited.
摘要:
A ceramic matrix composite with an enhanced abradability has a patterned surface with an array of solid composite material and voids where the voids extend into but not through the composite. The flow of gas through the voids as the surface is traversed by an impinging component, such as a turbine blade tip, is inhibited by the shape and size of the voids which can be sealed by the passing blade tip. Separately or additionally the inhibition of gas flow can result from the filling of the voids with a ceramic material of higher abradability than the ceramic matrix composite.
摘要:
A method of manufacturing a hybrid structure (100) having a layer of CMC material (28) defining an interior passageway (24) and a layer of ceramic insulating material (18) lining the passageway. The method includes the step of casting the insulating material to a first thickness required for effective casting but in excess of a desired second thickness for use of the hybrid structure. An inner mold (14) defining a net shape desired for the passageway remains in place after the casting step to mechanically support the insulating material during a machining process used to reduce the thickness of the insulating material from the as-cast first thickness to the desired second thickness. The inner mold also provides support as the CMC material is deposited onto the insulating material. The inner mold may include a fugitive material portion (20) to facilitate its removal after the CMC material is formed.
摘要:
Aspects of the invention are directed to a ceramic matrix composite ring seal segment. The ring seal segment according to aspects of the invention includes a relatively simple body that is circumferentially curved. At least a portion of the hot gas path surface of the ring seal segment can be coated with a thermal insulating. material. In one embodiment, each ring seal segment can be operatively connected to a stationary support structure, such as by way of isolation rings. The ring seal segments and/or the isolation rings can be configured so as to restrain the ring seal segments in the axial, radial and/or circumferential directions. The ring seal segments can be attached to the isolation rings so that the support points act opposite the operating pressure loads. Thus, the ring seal segments carry these loads in compression, a strong direction of the CMC fibers.