A porous refractory in the K.sub.2O—SiO.sub.2—B.sub.2O.sub.3 system is formed by chemical direct foaming by heating to over 600° C., resulting in adherent black or white foam. The foam can function as highly porous thermal insulation, a high or low thermal emissivity surface, as a sealant for deteriorated refractory surfaces, as a filler for pockmarks/holes/gaps or as a bonding agent for parts with large gaps between them.

The present disclosure provides a porous bulk material and an electronic apparatus thereof, and an apparatus capable of reducing wind noise and an application thereof. The apparatus comprises an external sound channel, a zeolite material, and a sound pickup hole, wherein the zeolite material is disposed between the external sound channel and the sound pickup hole. The present disclosure further provides an application of the apparatus in an electronic device provided with a microphone. According to the apparatus, the wind noise can be effectively reduced, and the call quality of a communication device is obviously improved.

A thermally-insulating composite material with co-shrinkage in the form of an insulating material formed by the inclusion of microballoons in a matrix material such that the microballoons and the matrix material exhibit co-shrinkage upon processing. The thermally-insulating composite material can be formed by a variety of microballoon-matrix material combinations such as polymer microballoons in a preceramic matrix material. The matrix materials generally contain fine rigid fillers.

A thermally-insulating composite material with co-shrinkage in the form of an insulating material formed by the inclusion of microballoons in a matrix material such that the microballoons and the matrix material exhibit co-shrinkage upon processing. The thermally-insulating composite material can be formed by a variety of microballoon-matrix material combinations such as polymer microballoons in a preceramic matrix material. The matrix materials generally contain fine rigid fillers.

A thermally-insulating composite material with co-shrinkage in the form of an insulating material formed by the inclusion of microballoons in a matrix material such that the microballoons and the matrix material exhibit co-shrinkage upon processing. The thermally-insulating composite material can be formed by a variety of microballoon-matrix material combinations such as polymer microballoons in a preceramic matrix material. The matrix materials generally contain fine rigid fillers.

A space filler for forming a fibrous preform may comprise an additively manufactured ceramic material. The additively manufactured ceramic material may define a plurality of pores. A shape of the additively manufactured ceramic material may complement a shape of a void formed by fibrous regions of the fibrous preform.

A space filler for forming a fibrous preform may comprise an additively manufactured ceramic material. The additively manufactured ceramic material may define a plurality of pores. A shape of the additively manufactured ceramic material may complement a shape of a void formed by fibrous regions of the fibrous preform.

The present disclosure relates to a method of fabricating a ceramic composite components. The method may include providing at least a first layer of reinforcing fiber material which may be a pre-impregnated fiber. An additively manufactured component may be provided on or near the first layer. A second layer of reinforcing fiber, which may be a pre-impregnated fiber may be formed on top the additively manufactured component. A precursor is densified to consolidates at least the first and second layer into a densified composite, wherein the additively manufactured material defines at least one cooling passage in the densified composite component.

The present disclosure relates to a method of fabricating a ceramic composite components. The method may include providing at least a first layer of reinforcing fiber material which may be a pre-impregnated fiber. An additively manufactured component may be provided on or near the first layer. A second layer of reinforcing fiber, which may be a pre-impregnated fiber may be formed on top the additively manufactured component. A precursor is densified to consolidates at least the first and second layer into a densified composite, wherein the additively manufactured material defines at least one cooling passage in the densified composite component.

The present disclosure relates to a method of fabricating a ceramic composite components. The method may include providing at least a first layer of reinforcing fiber material which may be a pre-impregnated fiber. An additively manufactured component may be provided on or near the first layer. A second layer of reinforcing fiber, which may be a pre-impregnated fiber may be formed on top the additively manufactured component. A precursor is densified to consolidates at least the first and second layer into a densified composite, wherein the additively manufactured material defines at least one cooling passage in the densified composite component.