The present invention provides a testing and characterization method for an initial fatigue damage and development process of vulcanized rubber, and falls within the technical field of rubber. The testing and characterization method comprises the following steps: preparing vulcanized rubber; preparing test samples; preparing fatigue testing specimens; and characterizing an initial fatigue damage and development process. The testing and characterization method provided by the present invention is simple, and closely associates a simple and easy-to-implement macro mechanical property test with changes of an internal microstructure, which are difficult to observe and analyze; and the method is high in efficiency and easy for operation and data collection, and data measured has good reference.

The present invention relates to a method for evaluating physical properties of a thin film specimen and a thin film specimen for a tensile test of the present invention, and according to the present invention, reliability of measured physical properties can be increased, and an abnormal damage of a thin film specimen can be suppressed by analyzing the strain rate of a speckle pattern formed on the thin film specimen by using a digital image correlation analysis scheme during a tensile test of the thin film specimen.

A bending apparatus for a sample is disclosed. The bending apparatus includes a translation mechanism that translates a vertical displacement/force into a horizontal displacement/force for bending. Components of the bending apparatus are fabricated from a strong, radiolucent material. In these ways, the bending apparatus is compatible with micro-CT imaging, and as such, may be used to bend a sample during imaging. In a particular application, the bending apparatus may be used to measure biomechanical properties of a bone, such as bone strength, bone material properties, fracture toughness, and fracture propagation.

A Bauschinger effect test fixture that cooperates with a test machine for stretching and compressing materials to perform a Bauschinger effect test on a test piece having a symmetrical configuration with two wide ends and a narrow middle part. The fixture includes two identical split bodies, where each split body has a base provided, longitudinally from a central part to one end of the base, with a limiting groove corresponding to a half of the profile of the test piece. Two sides of the groove are arranged symmetrically with a plurality of threaded through holes and a cover is provided along its central axis with two threaded through holes with which the test piece is pressed tightly by bolts. An end of the cover corresponding to a notch of the limiting groove is provided with a through groove configured for placing a stress ultrasonic detection probe on the test piece.

A system and method for identifying test bars formed during a selective laser sintering build. A part cake is formed during a selective laser sintering build. The part cake comprises parts formed from a powder by selective laser sintering and unsintered powder around the formed parts. The parts include test bars for performing material testing. Each test bar includes a plurality of indentations in a first grip section and a second grip section. The plurality of indentations are arranged in a information providing pattern that is adapted to be readable after the test part is removed from the part cake.

A coating bond test method includes, attaching with an adhesive a pull-off bar to a coating on a planar surface of a substrate for which a normal bond strength between the coating and the substrate is sought, reducing a first area defined by an interface between the substrate and the coating to a value less than a second area defined by an interface between the adhesive and the coating, urging the pull-off bar away from the substrate in a direction normal to the planar surface until failure occurs, and recording a load at which failure occurred.

A manufacturing method that includes fabricating a component using an additive manufacturing process, and fabricating a coupon using the additive manufacturing process. The coupon includes a main portion and a grip portion. Fabrication of the coupon includes fabricating the main portion concurrently with the fabrication of the component, fabricating the grip portion dissociatedly from the fabrication of the component, and coupling a first end of the main portion with the grip portion to form the coupon.

A bending apparatus for a sample is disclosed. The bending apparatus includes a translation mechanism that translates a vertical displacement/force into a horizontal displacement/force for bending. Components of the bending apparatus are fabricated from a strong, radiolucent material. In these ways, the bending apparatus is compatible with micro-CT imaging, and as such, may be used to bend a sample during imaging. In a particular application, the bending apparatus may be used to measure biomechanical properties of a bone, such as bone strength, bone material properties, fracture toughness, and fracture propagation.

The present disclosure describes systems and methods to correct for perspective calibration variations of a variable thickness specimen with a single camera extensometer in a video extensometer system. In some examples, the systems and methods compensate for a change between a reference characteristic, such as a calibration plane, and an actual physical characteristic, such as a testing plane associated with a surface of a test specimen, during a testing operation. In some examples, a correction value is applied to an output (e.g., measured dimensions of the imaged test specimen) to compensate for the difference between the reference characteristic and the physical characteristic.

A system can include a torsion applicator (e.g., a torsion motor and shaft) configured to apply a torque to a test article that is additively built on and attached to a build plate. The system can include at least one twist sensor and at least one torque sensor. A method for determining quality of an additively manufactured article or batch thereof can include torsion testing at least one additively manufactured test article that is built on and attached to a build plate while the at least one test article is still attached to the build plate.