Apparatus and methods of evaluating brittleness by measuring force applied to an electrode specimen by simulating a wound state of a jelly-roll type electrode assembly are disclosed herein. In an embodiment, a brittleness evaluation apparatus includes a jig unit, a driving unit, and a measurement analyzing unit. The jig unit includes two jigs, a groove formed between the jigs, a pressing plate, and guides. The jigs facing each other and have top surfaces formed in a horizontal plane and configured to receive a specimen arranged on the top surfaces along a length direction extending between and along the top surfaces. The pressing plate is arranged perpendicular to the length direction and configured to cause the specimen to bend by descending into the groove. The guides are located on each of the top surfaces of the jigs and configured to prevent distortion of the specimen during descent of the pressing plate.

A microfluidic chip having a micro channel for processing a sample is provided. The micro channel may focus the sample by using focusing fluid and a core stream forming geometry. The core stream forming geometry may include a lateral fluid focusing component and one or more vertical fluid focusing components. A microfluidic chip may include a plurality micro channels operating in parallel on a microfluidic chip.

A microfluidic chip having a micro channel for processing a sample is provided. The micro channel may focus the sample by using focusing fluid and a core stream forming geometry. The core stream forming geometry may include a lateral fluid focusing component and one or more vertical fluid focusing components. A microfluidic chip may include a plurality micro channels operating in parallel on a microfluidic chip.

Some materials desired to acquire mechanical characteristics and fatigue characteristics are difficult to make in a large-size bulk material for a test piece. The invention provides a test jig which includes a primary jig which fixes both sides of a test piece, which is a test object, an upper jig which includes a load portion to load a weight on two places of an upper surface and two places of a lower surface of the primary jig, and a lower jig which includes a load portion to load a weight on two places of the upper surface and two places of the lower surface of the primary jig. The upper surface and the lower surface of the primary jig disposed on both sides of the test piece are on almost the same flat surface.

A true stress testing system broadly comprising a force input machine, an imaging system, and a computer. The imaging system includes a light source for projecting a light beam at the specimen in a first direction and a camera positioned on an opposite side of the specimen for receiving portions of the light beam not blocked by the specimen such that a shadow image of the specimen is created via the camera. The computer may determine a minimum dimension of the specimen perpendicular to the first direction at a point in time over a plurality of points along the force axis via the shadow image of the specimen such that the processor accounts for changes in position of the minimum dimension along the specimen. A true stress of the specimen may then be determined according to the minimum dimension of the specimen perpendicular to the first direction at the point in time.

A true stress testing system broadly comprising a force input machine, an imaging system, and a computer. The imaging system includes a light source for projecting a light beam at the specimen in a first direction and a camera positioned on an opposite side of the specimen for receiving portions of the light beam not blocked by the specimen such that a shadow image of the specimen is created via the camera. The computer may determine a minimum dimension of the specimen perpendicular to the first direction at a point in time over a plurality of points along the force axis via the shadow image of the specimen such that the processor accounts for changes in position of the minimum dimension along the specimen. A true stress of the specimen may then be determined according to the minimum dimension of the specimen perpendicular to the first direction at the point in time.

Embodiments relate to a device for performing a bending test having a base plate, counter bearings connected via the base plate, bearing blocks which in each case comprise a support for applying a bending sample, and a bending punch or a bending rail for exerting a force on a bending sample. The distance of the supports can be set precisely and in a force resistant manner by abutting the counter bearings and the bearing blocks against each other via contact surfaces inclined to the base plate. Further provided is a method for performing a bending test using a device according to the invention, in the case of which a bending sample is applied on the supports and in the case of which a force is exerted between the supports on the bending sample.

Embodiments relate to a device for performing a bending test having a base plate, counter bearings connected via the base plate, bearing blocks which in each case comprise a support for applying a bending sample, and a bending punch or a bending rail for exerting a force on a bending sample. The distance of the supports can be set precisely and in a force resistant manner by abutting the counter bearings and the bearing blocks against each other via contact surfaces inclined to the base plate. Further provided is a method for performing a bending test using a device according to the invention, in the case of which a bending sample is applied on the supports and in the case of which a force is exerted between the supports on the bending sample.

An apparatus of testing a stick includes a tension unit that applies tension to a stick having openings formed therein and fixes the stick in place, a first testing unit that is spaced apart from the stick and tests a surface of the stick, a light dispersion unit that reflects light emitted from the first testing unit, a distance measurement unit that measures a third distance from a bottom surface of the stick to the light dispersion unit, and a control unit that calculates a second distance from a starting point of a protrusion of the stick tested by the first testing unit to the light dispersion unit, calculates a difference between the second distance and the third distance so as to calculate a height of the protrusion and determines whether the stick is defective or not, based on the height of the protrusion.

A strain testing rig for an elongate specimen has a first grip for the first end portion of the specimen, a second grip for the second end portion of the specimen, and a drive mechanism for moving the first grip away from the second grip to stretch the specimen lengthwise. The first grip and the second grip are configured to maintain a grip on the specimen as the cross section of the specimen decreases during stretching. Each of the first grip and the second grip can include a tapered dog, a press for compressing the respective end portion of the specimen, and a clamp for clamping the respective end portion of the specimen in a direction perpendicular to the action of the clamp. A method of testing strain characteristics can involve using digital image correlation to separately measure strain on each of the at least three independent strain zones.