A method for preparing a SiC ingot includes: disposing a raw material and a SiC seed crystal facing each other in a reactor having an internal space; subliming the raw material by controlling a temperature, a pressure, and an atmosphere of the internal space; growing the SiC ingot on the seed crystal; and collecting the SiC ingot after cooling the reactor. The wafer prepared from the ingot, which is prepared from the method, generates cracks when an impact is applied to a surface of the wafer, the impact is applied by an external impact source having mechanical energy, and a minimum value of the mechanical energy is 0.194 J to 0.475 J per unit area (cm.sup.2).

Apparatus and methods for impact testing of a transparent substrate are provided. The apparatus includes a base (110) for receiving the transparent substrate (112), the base having a curved surface (124) about which the transparent substrate is bent by a first fixture (130) and a second fixture (132). An abrasive sheet (136) is disposed between the transparent substrate and an impacting object (138) which is released from above the substrate such that the force from the impacting object causes damage to the transparent substrate while the transparent substrate is bent about the curved surface.

Apparatus and methods for impact testing of a transparent substrate are provided. The apparatus includes a base (110) for receiving the transparent substrate (112), the base having a curved surface (124) about which the transparent substrate is bent by a first fixture (130) and a second fixture (132). An abrasive sheet (136) is disposed between the transparent substrate and an impacting object (138) which is released from above the substrate such that the force from the impacting object causes damage to the transparent substrate while the transparent substrate is bent about the curved surface.

Apparatus and methods of for measuring stress incurred by a cover glass of a handheld device when the cover glass contacts a surface during a drop event. A transparent solid piece of material with a drop surface and a back surface is provided and oriented to receive a dropped handheld device so that the cover glass contacts the drop surface. At least two optical detectors are directed at the back surface of the transparent material to obtain image data including a plurality of pixel points.

Apparatus and methods of for measuring stress incurred by a cover glass of a handheld device when the cover glass contacts a surface during a drop event. A transparent solid piece of material with a drop surface and a back surface is provided and oriented to receive a dropped handheld device so that the cover glass contacts the drop surface. At least two optical detectors are directed at the back surface of the transparent material to obtain image data including a plurality of pixel points.

An impact test method and an impact test device is provided, wherein an impact application member is caused to fall freely onto a test sample placed on a placement platform. When the impact application member collides with the test sample, an impact force applied to the test sample and an indentation amount of the impact application member with respect to the test sample are measured by a load meter and a displacement meter, respectively. Based on the measured impact force and the measured indentation amount, a calculation unit calculates energy loss absorbed by the test sample when the impact application member and the test sample collide with each other.

An impact test method and an impact test device is provided, wherein an impact application member is caused to fall freely onto a test sample placed on a placement platform. When the impact application member collides with the test sample, an impact force applied to the test sample and an indentation amount of the impact application member with respect to the test sample are measured by a load meter and a displacement meter, respectively. Based on the measured impact force and the measured indentation amount, a calculation unit calculates energy loss absorbed by the test sample when the impact application member and the test sample collide with each other.

A foam backed composite panel having two or more layers of materials adhesively bonded to each other. The panel is comprised of a cementitious material as a face layer and/or an optional core layer backed by polyurethane foam bonded to the face or core layer. The polyurethane foam bonds the panel to a supporting frame. The foam backed panel has increased impact and fire resistance.

One example is a shock gauge system for measuring an external blast to a hull. The shock gauge system includes at least one accelerometer to produce acceleration data in response to the external blast, a mass with an accelerometer affixed to it, a crush block, a linear displacement potentiometer (LDP), a camera, and a processor logic. The LDP device generates displacement data of a mass being pushed into the crush block when reacting to the external blast. The camera captures images of movement of the mass. The processor logic verifies if the acceleration data is valid by correlating the acceleration data to the displacement data, the images, and/or an amount of displacement into the crush block by the mass. When the acceleration data is valid, the acceleration data may be used to create a more blast resistant hull.

The disclosure provides solid compositions such as lyophilisates adhered to surfaces such as plasma-treated surfaces and related methods, uses, kits, intermediates, starting materials, and downstream products.