A stretching and conveying device for a green compact includes a first roll and a second roll structured to convey by rotation the green compact by sandwiching the green compact between the first roll and the second roll and stretch the green compact using a circumferential speed difference between the first roll and the second roll. The second roll has a curvature radius larger than a curvature radius of the first roll, and is positioned downstream of the first roll. The green compact is conveyed while being supported on a circumferential surface of the first roll, delivered to the second roll side at a position where the first roll and the second roll face each other, and conveyed while being supported on a circumferential surface of the second roll.

A production method is provided. The production method comprises forming material by pressing or pulling ceramic material through a channel of an extrusion die, said channel being at least partly defined by the lateral surface area of at least one rotating die, and heat processing the formed material to form a ceramic product.

The present invention relates to a method for controlling physical properties of a silicon nitride substrate, and more specifically, the method comprises the steps of: producing a silicon nitride substrate; and adjusting a residual magnesium content in the silicon nitride substrate. The thermal conductivity of the silicon nitride substrate is inversely proportional to the residual magnesium content in the silicon nitride substrate, and the flexural strength of the silicon nitride substrate is proportional to the residual magnesium content in the silicon nitride substrate.

A method of preparing a ceramic fabric for use in a ceramic matrix composite includes transforming a ceramic tow from a first tow geometry to a second tow geometry, thereby reducing a first dimension of the ceramic tow and increasing a second dimension of the ceramic tow orthogonal to the first dimension to produce a flattened tow. The method includes weaving or braiding the flattened ceramic tow to form a ceramic fabric.