Abstract: A repetitive impact system is disclosed for testing soft material samples under controlled impact conditions. The system includes a drop tower with a moveable mass that is repeatedly lifted and dropped by a motor-driven rack and pinion mechanism. The pinion gear may be configured to fail before other components. A sample holder is positioned in the path of the mass and may contain foam and rubber layers on one or both surfaces. An accelerometer may detect horizontal acceleration exceeding a threshold, triggering a camera to capture images for cavitation analysis. The system may apply smooth acceleration trajectories and allow adjustment of impact height based on gear tooth configuration. A method is also disclosed for detecting initial cavitation nucleation by monitoring acceleration values during repeated impacts. This system enables precise, repeatable testing of soft materials and supports real-time detection of cavitation events.

Abstract: A method and device for electro-thermo-mechanical tensile testing of wires is disclosed. The device includes a sample frame having upper and lower parts, with the upper part coupled to the lower part through a plurality of sacrificial supports, the upper and lower parts each having an electrical contact pad. The upper and lower parts are electrically non-conductive. The device also includes a wire sample with tracking beads, the wire sample affixed to the upper and lower parts such that the electrical contact pads of the upper and lower parts are communicatively coupled through the wire sample. The device also includes a piezo actuator coupled to the upper part, a weight coupled to the lower part, a power supply configured to pass a current through the wire sample, an electronic balance beneath the weight, and a digital camera pointed at the tracking beads of the wire sample.

Abstract: Disclosed herein are composite wire materials with advantageous composition and structure that can provide improved mechanical properties. An example composite wire material includes a core wire including nickel (Ni), and a graphene-based layer on a surface of the core wire. Also disclosed are methods of making the composite wire material.

Abstract: A composite wire material may include a core wire including copper (Cu). The core wire material may include a first layer on a circumferential surface of the core wire, where the first layer includes graphene. The composite wire material may include a second layer on a circumferential surface of the first layer, where the second layer includes nickel (Ni).

Abstract: A method and device for electro-thermo-mechanical tensile testing of wires is disclosed. The device includes a sample frame having upper and lower parts, with the upper part coupled to the lower part through a plurality of sacrificial supports, the upper and lower parts each having an electrical contact pad. The upper and lower parts are electrically non-conductive. The device also includes a wire sample with tracking beads, the wire sample affixed to the upper and lower parts such that the electrical contact pads of the upper and lower parts are communicatively coupled through the wire sample. The device also includes a piezo actuator coupled to the upper part, a weight coupled to the lower part, a power supply configured to pass a current through the wire sample, an electronic balance beneath the weight, and a digital camera pointed at the tracking beads of the wire sample.

Abstract: A composite wire material may comprise a core wire comprising copper (Cu). The core wire material may comprise a first layer on a circumferential surface of the core wire, where the first layer comprises graphene. The composite wire material may comprise a second layer on a circumferential surface of the first layer, where the second layer comprises nickel (Ni).

Abstract: A system and method for studying cell injury mechanisms by applying biologically relevant mechanical impact to in vitro cell culture are disclosed. This approach is for maintaining consistent in vitro conditions during experiments, accommodating multiple cell populations, and monitoring each in real-time while achieving amplitude and time scale of input acceleration that mimic blunt injury cases. These multiplexed, environmental control capabilities enable characterizing the relationships between mechanical impact and cell injury in multivariate biological systems.

Abstract: A system for mechanical testing a specimen includes a 3D printed mechanical testing fixture; a linear actuator having an axis of movement; a controller configured to control the linear actuator; two cameras; a data-acquisition system configured to acquire data from the linear actuator, the controller, and the two cameras; and the specimen. The specimen is marked in two locations with tracking markers to provide indication to the data acquisition system via at least one camera of movement and change in length of the specimen. The fixture includes force-sensing beams extending perpendicular to the axis of force.

Abstract: A system for mechanical testing a specimen includes a 3D printed mechanical testing fixture; a linear actuator having an axis of movement; a controller configured to control the linear actuator; two cameras; a data-acquisition system configured to acquire data from the linear actuator, the controller, and the two cameras; and the specimen. The specimen is marked in two locations with tracking markers to provide indication to the data acquisition system via at least one camera of movement and change in length of the specimen.

Abstract: A system and method for studying cell injury mechanisms by applying biologically relevant mechanical impact to in vitro cell culture are disclosed. This approach is for maintaining consistent in vitro conditions during experiments, accommodating multiple cell populations, and monitoring each in real-time while achieving amplitude and time scale of input acceleration that mimic blunt injury cases. These multiplexed, environmental control capabilities enable characterizing the relationships between mechanical impact and cell injury in multivariate biological systems.

Abstract: According to example embodiments of the invention, a microscale testing stage comprises a frame having first and second opposing ends and first and second side beams, at least one deformable force sensor beam, a first longitudinal beam having a free end, a second longitudinal beam having a facing free end, a support structure, and a pair of slots disposed at each of the free ends. In certain embodiments, a layer of a conductive material defines first and second conductive paths and an open circuit that can be closed by the specimen across the gap. In other embodiments, the stage is formed of a high melting temperature material.

Abstract: According to example embodiments of the invention, a microscale testing stage comprises a frame having first and second opposing ends and first and second side beams, at least one deformable force sensor beam, a first longitudinal beam having a free end, a second longitudinal beam having a facing free end, a support structure, and a pair of slots disposed at each of the free ends. In certain embodiments, a separately fabricated microscale or nanoscale specimen comprises a central gauge length portion of a material to be tested, and first and second hinges providing a self-aligning mechanism for uniaxial loading. In other embodiments, a layer of a conductive material defines first and second conductive paths and an open circuit that can be closed by the specimen across the gap. In other embodiments, the stage is formed of a high melting temperature material.

Abstract: According to example embodiments of the invention, a microscale testing stage comprises a frame having first and second opposing ends and first and second side beams, at least one deformable force sensor beam, a first longitudinal beam having a free end, a second longitudinal beam having a facing free end, a support structure, and a pair of slots disposed at each of the free ends. In certain embodiments, a separately fabricated microscale or nanoscale specimen comprises a central gauge length portion of a material to be tested, and first and second hinges providing a self-aligning mechanism for uniaxial loading. In other embodiments, a layer of a conductive material defines first and second conductive paths and an open circuit that can be closed by the specimen across the gap. In other embodiments, the stage is formed of a high melting temperature material.