Disclosed are an apparatus for measuring an in-situ crosslink density includes a support configured to fix or support a cross-linkable structure, a light source configured to irradiate light for crosslinking to the cross-linkable structure, and a probe configured to provide in-situ micro-deformation to the cross-linkable structure, wherein the in-situ crosslink density of the cross-linkable structure is measured from a stress-strain phase lag of the cross-linkable structure by the in-situ micro-deformation, a method of measuring the in-situ crosslink density, a method of manufacturing a crosslinked product, a crosslinked product obtained by the method, and a polymer substrate and an electronic device including the crosslinked product.

Disclosed are a hydro-mechanical coupling experimental device with CT real-time scanning and a use method thereof. The hydro-mechanical coupling experimental device with the CT real-time scanning includes a CT scanning room and further includes a support frame, a hydro-mechanical coupling mechanism and a jack that are arranged in the CT scanning room. The support frame includes a base, a top plate, a plurality of columns for arranging the top plate and the base at intervals, and a movable plate that is arranged between the top plate and the base and can slide on the plurality of columns. The hydro-mechanical coupling mechanism includes an experimental box, a pressure box arranged inside the experimental box and a compression leg slidingly worn on a top of the experimental box; and the experimental box is arranged on the movable plate, and the jack is arranged on the base.

A method of displaying stress distribution on a sample surface includes: step S4 of capturing images of the sample surface before loading, during the loading, and after unloading; step S5 of measuring a first strain amount for each pixel position based on correlation between the image before the loading and the image after the unloading; step S6 of measuring a second strain amount for each pixel position based on correlation between the image before the loading and the image during the loading; step S7 of calculating stress for each pixel position based on the difference between the first strain amount and the second strain amount; and step S8 of displaying the distribution of the calculated stress at each pixel position.

A performance evaluation method for elastic material including rubber or elastomer, the method includes a step of applying a strain to a test piece made of the elastic material to form at least one void inside the test piece, a step of obtaining projected images of the test piece by irradiating the test piece with X-rays at a plurality of times after the at least one void is formed, and a step of obtaining a volume change of the at least one void between the plurality of times based on the projected images, as one of indexes of performance.

A fracture toughness testing machine of the invention makes it possible to evaluate fracture toughness of a specimen in pure mode such that the effect of thermal residual stresses is removed, when the stresses are present in the specimen obtained by bonding dissimilar materials. The testing machine includes: testing-load applying means for applying a predetermined testing load to the specimen, in which the stresses are present; and cancelling-load applying means for applying a cancelling load to the specimen to cancel the stresses therein. The cancelling-load applying means includes: a pressing-force applying portion that applies a pressing force to the specimen as the canceling load; and a pressing-force determining portion that determines magnitude of the force. The pressing-force determining portion calculates the magnitude of the force using pre-stored equations so that an energy release rate related to in-plane shear mode crack deformation becomes zero.

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 test method for characterizing the mechanical properties including the surface adhesion energy γ on the basis of the experimentally derived P-A relationship, where P means the indentation load under the penetration depth h of an indenter pressed onto a test specimen with surface adhesion, and A means the contact area of indentation at the contact radius a under the applied load of P. This test method enables the implementation for quantitatively as well as simultaneously characterizing the adhesion energy as well as the various mechanical properties (elastic/elastoplastic/viscoelastic properties) of soft materials.

A system for simultaneously measuring the indentation hardness properties, span properties, and resilience properties of a mattress includes a first indentation means and a second indentation means, and means for urging the first indentation means and the second indentation means into the mattress with a predetermined force, and also includes laser means for projecting a laser line configured to map, preferably by photographic triangulation, the amplitude, shape, and time-dependency of the resultant deflection of the mattress surface between the first indentation means and the second indentation means. A method for simultaneously measuring the indentation hardness properties, span properties, and resilience properties of a mattress is also provided.

The present invention relates to a device for measuring residual stress and hardness. Residual stress remaining in a metallic material due to deformation, thermal stress, or the like is a cause of various problems including degradation of mechanical properties such as fatigue strength and fracture properties and difficulty in post-processing. It is very difficult to derive a calibration curve when measuring stress by an existing non-destructive Barkhausen noise measurement method. When cross points of Barkhausen noise measurements for three or more stresses are not at one position, calibrated curves can be easily found by scaling the Barkhausen noise measurements by using calibration equations of the present invention to collect the cross points at a unique position, thereby providing a practical method of easily measuring stress of a metal by a Barkhausen noise measurement method. Therefore, according to the present invention, it is found that the internal microstructure and surface residual stress of a metal cause crossing points not to be at a unique position in a conventional Barkhausen noise measurement experiment. In addition, basic physical properties and surface residual stress of a metallic material may be measured using the above-mentioned physical feature.

An instrument and method for mechanical properties in situ testing of materials under a high temperature and complex mechanical loads are provided. The instrument includes: a support frame module used to provide a stable support and an effective vibration isolation for each functional module of the instrument; a high-frequency fatigue load applying module used to apply a high-frequency fatigue load on a tested sample; a static-dynamic mechanical load applying module used to apply a combination of static-dynamic tension/compression/bending loads on the tested sample; a high/low temperature applying module used to apply a variable temperature environment from a low temperature to a high temperature on the tested sample; and an in-situ monitoring module that may integrate a surface deformation damage measurement assembly, a three-dimensional strain measurement assembly, a microstructure measurement assembly, and an internal damage detection assembly according to a practical testing requirement.