Provided are a cover-layer-including ceramic continuous fiber suitable for producing a ceramic matrix composite material that can have improved damage tolerance and a ceramic matrix composite material formed from the cover-layer-including ceramic continuous fiber. The cover-layer-including ceramic continuous fiber includes a ceramic continuous fiber and a cover layer formed of an inorganic acid salt and disposed on the surface of the ceramic continuous fiber, wherein the thickness variation coefficient of the cover layer is 80% or less.

Disclosed is a method of making high temperature fiber including chemically bonding high temperature material to a fiber template at a first temperature to form a precursor fiber and processing the precursor fiber at a second temperature to form the high temperature fiber. The first temperature does not equal the second temperature. Also disclosed are high temperature fibers made by the method.

A cathode having a tandem electrocatalyst structure is provided. The cathode includes a plurality of wires spaced apart from each other, a layer formed on a surface of each of the plurality of wires, and a plurality of nanoparticles disposed on the layer. Each of the plurality of wires includes a first perovskite material or a metal. The layer includes a second perovskite material. Each of the nanoparticles includes a metal oxide.

A method is provided in which multiple layers are formed. Each of the layers includes at least a first set of ceramic fibers and a second set of ceramic fibers. The first set is arranged at an angle with respect to the second set. The first set and the second set define a plurality of pores therebetween. The layers are arranged on top of each other to form a porous preform. The pores of the layers arranged on top of each other are aligned. The pores define a plurality of channels extending continuously through the porous preform from a first side of the porous preform to a second side of the porous preform. Each channel comprises one inlet at the first side of the porous preform and one outlet at the second side of the porous preform. The porous preform is infiltrated with a matrix material.

Provided herein is a method of making a conductive network by combining uncoated carbon nanotubes and carbon nanotubes coated with an electroactive substance to create an electrically conductive network; and redistributing at least a portion of the electroactive substance. Also provided herein is an electrically conductive network with an active material coating; first carbon nanotubes coated with the active material coating; and second carbon nanotubes partially coated with the active material coating, wherein at least a portion of the surfaces of the second carbon nanotubes directly contact surfaces of other second carbon nanotubes without the active material coating between these second carbon nanotubes, and wherein the first carbon nanotubes and the second carbon nanotubes are entangled to form an electrically conductive network.

A fiber comprises a bulk material comprising: one or more of carbon, silicon, boron, silicon carbide, and boron nitride; and a metal or metal alloy whose affinity for oxygen is greater than that of the bulk material. At least a first portion of the metal or metal alloy is present at the entrance to grain boundaries at the surface of the fiber and within the fiber to a depth of at least 1 micron from the fiber surface.

A method of improving a fiber comprises heating a fiber in an inert atmosphere to 900-1300 C for sufficient time to allow at least some of a metal or metal alloy, placed on the fiber, to diffuse and/or flow into and along grain boundaries to a depth of at least 1 micron. The metal or metal alloy has a greater affinity for oxygen than that of the fiber bulk material.

A fiber comprises a bulk material comprising one or more materials selected from the group consisting of carbon, silicon, boron, silicon carbide, and boron nitride; and a metal whose affinity for oxygen is greater than the affinity for oxygen of any of the one or more materials. The metal may be selected from the group consisting of beryllium, titanium, hafnium and zirconium. At least a first portion of the metal may be present in un-oxidized form at the entrance to and/or within grain boundaries within the fiber. A method of improving at least one of the strength, creep resistance, and toughness of a fiber comprises adding to a fiber, initially comprising a bulk material having a first affinity for oxygen, a metal that has a second affinity for oxygen higher than the first affinity. The metal may be selected from the group consisting of beryllium, titanium, hafnium and zirconium.

Provided herein is a method of manufacturing a nanoscale coated network, which includes providing nanofibers, capable of forming a network in the presence of a liquid vehicle and providing a nanoscale solid substance in the presence of the liquid vehicle. The method may also include forming a network of the nanofibers and the nanoscale solid substance and redistributing at least a portion of the nanoscale solid substance within the network to produce a network of nanofibers coated with the nanoscale solid substance. Also provided herein is a nanoscale coated network with an active material coating that is redistributed to cover and electrochemically isolate the network from materials outside the network.

A blade for a gas turbine engine, and methods of manufacture of such a blade having a continuous density gradient so that the portion of the blade nearest the rotator shaft is of a higher density than the portion of the blade furthest from the rotator shaft.

A method of additively manufacturing a ceramic matrix composite material includes providing a ceramic fiber and a powdery base material for a ceramic matrix composite and layer-by-layer building up the ceramic matrix material for the ceramic matrix composite by irradiating of a powder bed formed by the base material with an energy beam according to a predetermined geometry, wherein the base material is remelted, solidified and adhesively joined to the ceramic fiber in that parameters of the energy beam are locally chosen such that in the contact region of the ceramic fiber and the powder bed, the ceramic fiber is only partly remelted.