The present disclosure relates to a traceable in-situ micro- and nano-indentation testing instrument and method under variable temperature conditions. A macro-micro switchable mechanical loading module, a nano mechanical loading module and an indentation position optical positioning module are fixed on a gantry beam, an optical imaging axis of an optical microscopic in-situ observation or alignment module and a loading axis of the nano mechanical loading module are coplanar, the optical microscopic in-situ observation or alignment module and the function switchable module are mounted on a table top of a marble pedestal, and a contact or ambient mixed variable temperature module is fixedly mounted on the function switchable module. A modular design is adopted, the micro- and nano-indentation testing instrument is used as a core, in combination with a multi-stage vacuum or ambient chamber, an indentation depth traceability calibration module and multiple sets of optical microscopic imaging assemblies.

A device for evaluating working surface fretting wear characteristics comprises a bottom holder with a sample secured thereto, springs displacing in the X and Y direction, multilayer piezo elements moving in the X, Y, and Z directions, a housing, a top plate/holder, a linear air bearing housing, a spherical upper sample, a linear air bearing shaft, a three-way force sensor, a moving support of the flat air bearing and the flat air bearing housing, a high frequency generator, an amplifier, a controller, an electrical filter, a computer, a force sensor signal amplifier, and a flat air bearing. Instead of springs, it can comprise additional multilayer piezo elements moving in the X and Y directions. The device performs testing surface wear under conditions nearer to actual fretting wear conditions, continuously observing friction pair condition changes during testing and evaluating wear characteristics of the tested material more accurately.

The present invention provides a method of surely detecting a crack in piezoelectric elements regardless of size of the crack. The method includes applying voltage to a first piezoelectric element of a pair of piezoelectric elements to cause deformation in the first piezoelectric element, forcibly deforming a second piezoelectric element of the pair of the piezoelectric elements to generate voltage from the second piezoelectric element according to the deformation of the first piezoelectric element, finding a transfer function of the pair of the piezoelectric elements based on values of the applied voltage and the generated voltage, and detecting presence or absence of a crack in the pair of the piezoelectric elements based on an objective value obtained from the found transfer function.

A test system includes a frame. A hydraulic actuator is mounted to the frame and is configured to support a test specimen. A piezoelectric actuator is configured to apply a force to the test specimen. A controller is configured to excite the piezoelectric actuator and provide an indication of force generated by the piezoelectric actuator by measurement of current or charge provided to the piezoelectric actuator.

A MEMS-nanoindenter chip performs nanoindentation on a specimen. The MEMS-nanoindenter chip has an intender probe joined with an indenter tip. The indenter tip indents into the specimen. A reference probe is joined with a reference tip, the reference tip touches the specimen. Sensing capabilities are provided to measure the position of the indenter probe relative to the reference probe. The MEMS-nanoindenter chip enables highly accurate measurements since the frame stiffness is not part of the measurement chain any more. Furthermore, thermal drift during the nanoindentation is considerably reduced.

The present disclosure relates to a traceable in-situ micro- and nano-indentation testing instrument and method under variable temperature conditions. A macro-micro switchable mechanical loading module, a nano mechanical loading module and an indentation position optical positioning module are fixed on a gantry beam, an optical imaging axis of an optical microscopic in-situ observation or alignment module and a loading axis of the nano mechanical loading module are coplanar, the optical microscopic in-situ observation or alignment module and the function switchable module are mounted on a table top of a marble pedestal, and a contact or ambient mixed variable temperature module is fixedly mounted on the function switchable module. A modular design is adopted, the micro- and nano-indentation testing instrument is used as a core, in combination with a multi-stage vacuum or ambient chamber, an indentation depth traceability calibration module and multiple sets of optical microscopic imaging assemblies.

A measuring device for detection pf measurement signals during a penetrating movement of a penetrating member into a surface of a test object or during a sensing movement of the penetrating member on the surface of the test object. The measuring device includes a housing which accommodates a force generating device and on which a holding element is arranged remote from the force generating device, which holding element is movable relative to the housing at least in one direction along a longitudinal axis of the housing and which accommodates the penetrating member. The measuring device also includes at least one first measuring element for measuring the penetration depth of the penetrating member into the surface of the test object or a traversing movement of the penetrating member along the longitudinal axis relative to the housing during a sensing movement on the surface of the test object, wherein a transmission element is provided which extends between the force generating device and the penetrating member.

A measuring device for detection pf measurement signals during a penetrating movement of a penetrating member into a surface of a test object or during a sensing movement of the penetrating member on the surface of the test object. The measuring device includes a housing which accommodates a force generating device and on which a holding element is arranged remote from the force generating device, which holding element is movable relative to the housing at least in one direction along a longitudinal axis of the housing and which accommodates the penetrating member. The measuring device also includes at least one first measuring element for measuring the penetration depth of the penetrating member into the surface of the test object or a traversing movement of the penetrating member along the longitudinal axis relative to the housing during a sensing movement on the surface of the test object, wherein a transmission element is provided which extends between the force generating device and the penetrating member.

A dynamic mechanical analysis system provides an actuator that imparts expansion and contraction forces (e.g. shear force) to a viscoelastic material at high frequencies. Such high frequency analysis allows for the direct and accurate measurement of the characteristics of the material at high expansion/contraction frequencies directly, without the use of additional predictive analysis techniques, such as time-temperature superposition. The system also utilizes a clamping system, whereby two different sections of the viscoelastic material are held in place between by a pair of fixed clamps and a force member that is moved by the actuator. As such, the system is able to subject the viscoelastic material sample to simulated road conditions to identify various performance properties associated with the material sample.

An electroacoustic device includes at least one precursor wave transducer. The at least one precursor wave transducer includes a piezoelectric substrate, and first and second electrodes of inverse polarity arranged on the substrate and configured to generate in the substrate a precursor ultrasonic surface wave which is unfocused. When a fluid medium is acoustically coupled with the electroacoustic device, the precursor ultrasonic surface wave propagates as a volume acoustic wave into the bulk of the fluid medium and focuses therein.