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).

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).

A falling-object protective structures (FOPS) test assembly for carrying a FOPS test of a wall of cab of a heavy vehicle is configured to releasably carry a test ball for the FOPS test above a predefined distance above wall. The FOPS test assembly defines a closed path for test ball from its housing position to wall, and includes a handling means configured to assume a first condition in which they do not interfere with the passage of test ball through the closed path when ball passes through closed path in a first direction and a second condition in which handling means lock and hold test ball within the closed path once test ball passes again through the closed path in a second direction opposite to the first direction.

A falling-object protective structures (FOPS) test assembly for carrying a FOPS test of a wall of cab of a heavy vehicle is configured to releasably carry a test ball for the FOPS test above a predefined distance above wall. The FOPS test assembly defines a closed path for test ball from its housing position to wall, and includes a handling means configured to assume a first condition in which they do not interfere with the passage of test ball through the closed path when ball passes through closed path in a first direction and a second condition in which handling means lock and hold test ball within the closed path once test ball passes again through the closed path in a second direction opposite to the first direction.

An impact resistance test method of a glove having a protective material includes applying an impact force, with an impactor, to the glove at a plurality of locations on a section of the glove, measuring, with a load cell, a transferred impact force transferred through the section of the glove, and determining an impact resistance of the glove based on the measured transferred impact force. The impactor has a predetermined weight and is dropped from a predetermined height to apply the impact force to the section of the glove. An apparatus for carrying out the test method is also provided.

An impact resistance test method of a glove having a protective material includes applying an impact force, with an impactor, to the glove at a plurality of locations on a section of the glove, measuring, with a load cell, a transferred impact force transferred through the section of the glove, and determining an impact resistance of the glove based on the measured transferred impact force. The impactor has a predetermined weight and is dropped from a predetermined height to apply the impact force to the section of the glove. An apparatus for carrying out the test method is also provided.

A method for testing a sample for ball dent properties is provided. The method comprises disposing a sample on a stage of a testing apparatus and moving a trigger assembly that contains a tip having a radiused terminus toward the sample such that the terminus impacts the sample one or more times.

A method for testing a sample for ball dent properties is provided. The method comprises disposing a sample on a stage of a testing apparatus and moving a trigger assembly that contains a tip having a radiused terminus toward the sample such that the terminus impacts the sample one or more times.

A window drop test apparatus includes a support protruding in a first direction from the prop, and a guide portion that defines a drop space together with the support, where a drop test is performed through the drop space.

A window drop test apparatus includes a support protruding in a first direction from the prop, and a guide portion that defines a drop space together with the support, where a drop test is performed through the drop space.