Disclosed is an anti-buckling jig of a fracture toughness test. The anti-buckling jig includes: a first jig unit provided in a form of surrounding one side surface of a specimen; a second jig unit provided in a form of surrounding the other side surface of the specimen; and a screw provided to allow the first jig unit and the second jig unit to be coupled to each other. During the fracture toughness test of the specimen, the first jig unit and the second jig unit simultaneously support both sides of the specimen, so that the specimen is cracked in a single direction.

A rock mass shear test system for high-energy accelerator computed tomography (CT) scanning includes double horizontal loading devices, a first bearing device for bearing a static shear box, a second bearing device for bearing a dynamic shear box, and a normal loading device, etc. In the test, the double horizontal loading devices simultaneously apply an identical loading force to the rock mass, and the normal loading device applies a shear force to the rock mass. The double horizontal loading devices are provided in parallel and spaced apart, a loading force is applied in the horizontal direction, and a shear force is applied in the vertical direction, so that the loading cylinder and the rock mass sample are effectively prevented from interfering with each other during the accurate scanning process of the shearing progressive failure process of the rock mass.

A method for identifying a necking limit strain of a metal sheet includes a step of measuring the distribution of strain in a tensile orthogonal direction in a tensile deformation process of a notch root for two or more types of sheet specimens having a notch geometry in a portion of a sheet edge; a step of obtaining a strain increment ratio of the notch root in the tensile deformation process and a strain gradient in the tensile orthogonal direction; a step of obtaining necking limit strain at which necking occurs in the notch root based on the strain increment ratio in the tensile deformation process; and a step of identifying the necking limit strain as a function of the strain gradient from the relation between the necking limit strain obtained for the two or more types of sheet specimens and the strain gradient at that time.

A method of testing a semiconductor device includes forming conductive bumps respectively on a plurality of bonding pads of the semiconductor device. The semiconductor device having the conductive bumps is supported on a substrate stage. A gripper having first and second holders spaced apart from each other is positioned over the conductive bump. The conductive bump is clamped between the first and second holders. The gripper clamping the conductive bump is reciprocated at a constant speed with a predetermined stroke in a horizontal direction parallel with an upper surface of the substrate stage. A reliability of the semiconductor device is determined by measuring a time point at which a crack occurs in an upper wiring connected to the bonding pad.

The present invention discloses a method for detecting the mechanical response of a mechanical component by an organic mechanoresponsive fluorescent material, comprising the following steps of: selecting an organic mechanoresponsive fluorescent material; preparing an organic mechanoresponsive fluorescent material solution; forming a film on a metal surface; calibrating fluorescence intensity and obtaining the fluorescence intensity and distribution in a crack tip area; observing the fluorescence signal generated at cracks to monitor the occurrence of fatigue cracks, and predict a propagation pathway of fatigue cracks by using the fluorescence intensity distribution in the crack tip area.

Systems and methods for testing shear bond strength of cement with a composite sample under downhole conditions form a bonding surface of the sample oriented at an angle between 50 and 70 degrees from a plane perpendicular to a longitudinal axis of the sample. The composite sample is formed by bonding the cement to the sample with the cement in contact with the bonding surface of the sample.

The present disclosure relates to a method for determining initiation positions of fretting fatigue cracks. The processed inner circular hole test workpiece is placed on a stage of an optical microscope, wherein the inner hole surface to be measured is perpendicular to the scanning beam direction of the microscope; measurement is performed along the real contact orientation between the inner hole surface of the inner circular hole test workpiece and the pin shaft. From the measured surface morphology and profile image, rectangular target areas with a coverage rate of 75%˜90%, and the amplitude distribution function, surface skewness and surface kurtosis values of the respective surface profiles are extracted from the target areas. By comparing the positive/negative of and the magnitude of the skewness and kurtosis values measured in the target areas, the side where the initiation position of fretting fatigue cracks is located can be determined.

The present invention discloses a method for detecting the mechanical response of a mechanical component by an organic mechanoresponsive fluorescent material, comprising the following steps of: selecting an organic mechanoresponsive fluorescent material; preparing an organic mechanoresponsive fluorescent material solution; forming a film on a metal surface; calibrating fluorescence intensity and obtaining the fluorescence intensity and distribution in a crack tip area; observing the fluorescence signal generated at cracks to monitor the occurrence of fatigue cracks, and predict a propagation pathway of fatigue cracks by using the fluorescence intensity distribution in the crack tip area.

A method for determining rock properties includes running a downhole tool into a wellbore formed from a terranean surface to a subterranean zone that includes an underground rock formation, the downhole tool including one or more protrusions coupled with at least one expandable member of the downhole tool, the one or more protrusions including memory metal; actuating the downhole tool, at a location in the wellbore adjacent the underground rock formation, to adjust the at least one expandable member to move the one or more protrusions into or near contact with the underground rock formation; activating the one or more protrusions to fracture the underground rock formation through forcible contact between the one or more protrusions and the underground rock formation; determining a wellbore pressure increase at the location in the wellbore based on the fracture; and determining one or more properties of the underground rock formation based at least in part on the determined wellbore pressure increase.

A method for estimating life of a component includes obtaining fracture data corresponding to a component. The fracture data includes a first dataset corresponding to a threshold region where the crack in the component is dormant below a fatigue threshold. The method further includes determining initial estimates of parameters of a crack growth rate model and parameters of temperature models corresponding to the crack growth rate model based on the fracture data. The method also includes computing optimized parameters of temperature models corresponding to the crack growth rate model, and a scatter parameter via simulation of a joint optimization method using the initial estimates. The method includes determining a cumulative distribution function based on the optimized parameters and the scatter parameter and estimating life of the component based on the cumulative distribution function.