Abstract: A flow test machine 2 which, for example, is able to be used for viscosity tests on plastics, comprises a test piston 4, a test channel 38, at least one test weight 72 and a drive unit 92. The test piston 4 is able to move through the test channel 38 by means of a weight force 79 of the test weight 72. The test weight 72 is able to be loaded by an actuating additional force 108, 108? by means of the drive unit 92 between a starting position 151 and an end position. The actuating additional force 108 enables a movement of the test piston 4 in the direction of the weight force 79, said movement being accelerated in comparison with an effect of the weight force 79. In a melt viscosity test, after a heating step, a thermoplastic plastic is pressed through a test channel 38 by a test piston 4. In a measurement preparation step and/or a cleaning step, the test mass is lowered along a weight force direction 79 under the influence of an actuating additional force 108, 108?.

Abstract: An industrial machine includes a moving mechanism moving one of a probe and a tool relative to a work piece, using three displacement axes parallel to each of three orthogonal axis directions; a low thermal expansion member formed with a material having a smaller thermal expansion coefficient than a material forming a structural element of the moving mechanism; and an expansion/contraction measurer measuring, using the low thermal expansion member as a reference, an amount of expansion/contraction of the structural element in one of the three orthogonal axis directions, the expansion/contraction occurring due to a change in temperature.

Abstract: A dilatometer for measuring metallic samples. The dilatometer includes a sample holder configured to receive and clamp a sample, an induction coil arranged on the sample, the induction coil configured to heat the sample, and a sensor for measuring the temperature of the sample.

Abstract: An ultrasensitive ratiometric capacitance dilatometer and related methods are described. The dilatometer provides a capacitance measurement based on a ratiometric capacitance, or the capacitance ratio measured between two or more parallel plate capacitors of the dilatometer. In this regard, an absolute capacity bridge is not required, and even more advantageously, the effects of adsorbed gas are greatly reduced compared to conventional dilatometers. The ratiometric capacitance dilatometer provides a symmetrical configuration, which reduces the effects of temperature gradients. Moreover, certain embodiments provide a “v-groove design”, wherein a first parallel plate capacitor forms an angle with a second parallel plate capacitor of the dilatometer along a key centerline of the dilatometer cell, which improves manufacturability due to simpler grinding, metalizing and assembly.

Abstract: In an overlay displacement amount measuring method according to an embodiment, a temperature distribution of a substrate during a pattern forming process and a temperature distribution of the substrate during a measuring process for measuring a positional displacement amount between patterns on the substrate by an electron microscope are measured. An expansion/contraction amount of the substrate between two processes is calculated based upon the two temperature distributions, and the positional displacement amount is corrected based upon the expansion/contraction amount. An overlay displacement amount between the pattern and a pattern formed on a layer different from the pattern is measured by an optical measuring apparatus, and the overlay displacement amount is corrected based upon the corrected positional displacement amount.

Abstract: An ultrasensitive ratiometric capacitance dilatometer and related methods are described. The dilatometer provides a capacitance measurement based on a ratiometric capacitance, or the capacitance ratio measured between two or more parallel plate capacitors of the dilatometer. In this regard, an absolute capacity bridge is not required, and even more advantageously, the effects of adsorbed gas are greatly reduced compared to conventional dilatometers. The ratiometric capacitance dilatometer provides a symmetrical configuration, which reduces the effects of temperature gradients. Moreover, certain embodiments provide a “v-groove design”, wherein a first parallel plate capacitor forms an angle with a second parallel plate capacitor of the dilatometer along a key centerline of the dilatometer cell, which improves manufacturability due to simpler grinding, metalizing and assembly.

Abstract: An apparatus for measuring cement expansion comprises an expansion cell that comprises two nodes separated by a slit. The nodes are separated by a distance such that a change of the distance between the nodes may be correlated to a linear expansion of cement contained in the expansion cell. An electrical component is coupled to the two nodes, and the electrical component has an electrical property that may be correlated to the distance between the nodes. Measurement of the electrical-property change may be performed continuously and in real time. In addition, the expansion cell may be placed in a vessel equipped to simulate downhole pressure and temperature conditions.

Abstract: An in situ device for soil investigation including a probe for inserting into and advancing into the ground, the probe including: at least one dilatometer presenting at least one expandable membrane, a chamber for fluid to be fed to the dilatometer and expand the membrane, a compression/pressure regulator unit connected to the chamber and dilatometer, to generate and/or regulate the fluid pressure, a control unit for the connector and the dilatometer, electrical powering unit to power the dilatometer, compression/pressure regulator unit, control unit, and a pressure measurement unit, unit for storing pressure values, measured by the measurement unit, for the fluid fed to said dilatometer. These components all housed within the probe. The probe being a closed body without connections to the outside for feeding pressurized fluid to the dilatometer and/or for feeding control signals for the device. The chamber being the only fluid feed source for the dilatometer.

Abstract: The abnormality detection apparatus includes a first function of measuring a first temperature of a first portion of the abnormality detection apparatus, the first temperature having a correlation with a second temperature of a second portion of a vehicle alternator, a second function of integrating a stress depending on a temperature variation of the first portion on the basis of the first temperature measured by the first function, a third function of predicting occurrence of abnormality in the second portion depending on the stress integrated by the second function, and a fourth function of issuing an alarm when the third function predicts occurrence of abnormality.

Abstract: Elongation measurement apparatuses and systems comprise at least two Linear Variable Differential Transformers (LVDTs) with a push rod coupled to each of the at least two LVDTs at one longitudinal end thereof. At least one push rod extends to a base and is coupled thereto at an opposing longitudinal end, and at least one other push rod extends to a location spaced apart from the base and is configured to receive a sample between an opposing longitudinal end of the at least one other push rod and the base. Nuclear reactors comprising such apparatuses and systems and methods of measuring elongation of a material are also disclosed.

Abstract: After a thermal displacement correcting program has started, a temperature is measured with a temperature sensor in S1, then when a rotational speed of a spindle is changed during the measurement (S2), a counter starts (S3). Then in S4, from a preset relationship between the rotational speed of the spindle and a setting-equivalent heat value, a correction factor that is a difference in setting-equivalent heat value between before and after the change in rotational speed of the spindle is calculated. Subsequently, in S5, a temperature-equivalent heat value is calculated, and then in S6, a compensation amount is calculated from the correction factor and a time elapsed after the change in rotational speed of the spindle. In S7, an equivalent heat value for compensating a dead time is obtained based on the sum of them S8, an estimated calculation for thermal displacement conversion is performed, and a correction process by an NC unit is performed in S9.

Abstract: In a thermomechanical measuring device and a thermogravimetry device, partition walls are provided in two sections such that two kinds of atmospheric gasses, which have passed a sample chamber and a detector chamber, respectively, do not flow back, and a thermally insulated gas mixing chamber is manufactured anew in the middle of the sample chamber and the detector chamber to make it possible to dilute a reactive gas and a water vapor gas having a high partial pressure. Consequently, it is possible to prevent moisture concentration to reduce an influence of water drops even in a high temperature and high humidity state at the time of humidity control and measurement.

Abstract: A device for testing a material that changes shape when an electric and/or magnetic field is applied, in particular a piezoactive material, having a generator to generate an electric field and/or a magnetic field is described. This permits a rapid characterization of the material and at the same time can be implemented with a much lower structural complexity. This is achieved by the fact that at least one thermal sensor is provided for detecting a change in temperature of the material.

Abstract: A calibration apparatus for calibrating a linear variable differential transformer (LVDT) having an armature positioned in au LVDT armature orifice, and the armature able to move along an axis of movement. The calibration apparatus includes a heating mechanism with an internal chamber, a temperature measuring mechanism for measuring the temperature of the LVDT, a fixture mechanism with an internal chamber for at least partially accepting the LVDT and for securing the LVDT within the heating mechanism internal chamber, a moving mechanism for moving the armature, a position measurement mechanism for measuring the position of the armature, and an output voltage measurement mechanism. A method for calibrating an LVDT, including the steps of: powering the LVDT; heating the LVDT to a desired temperature; measuring the position of the armature with respect to the armature orifice; and measuring the output voltage of the LVDT.

Abstract: A method for determining the Coefficient of Thermal Expansion of a specimen. The specimen is placed in the tester and a tensile force is applied to the specimen. The specimen is equilibrated at a first temperature and then elongated. After reaching a desired elongation, the specimen is equilibrated at another temperature. The tensile force on the specimen is changed to a predetermined value or until the specimen fails. A force-displacement curve is generated from the stressed specimen. The force-displacement curve is converted into a stress-strain response, from which the Coefficient of Thermal Expansion is determined.

Abstract: A method is provided for aligning the center frequency of an infrared transmitter. The method comprises the steps of: (a) providing a voltage-controlled oscillator for driving the infrared transmitter, where the oscillator is adapted to receive a bias voltage from a microprocessor; (b) applying a bias voltage to the oscillator; (c) receiving an output signal from the infrared transmitter into an infrared receiver; (d) determining a frequency associated with the output signal; and (e) adjusting the bias voltage based on the frequency associated with the output signal, thereby aligning the center frequency of the infrared transmitter.

Abstract: The present invention is a method to eliminate the influence of clamp dimensional changes on the displacement measurement during the measurement of the coefficient of thermal expansion (CTE) of samples in tension. In a first embodiment clamp dimensional changes can be eliminated by making clamps from a material with near zero CTEs. In another embodiment clamp dimensional changes can be reduced by minimizing the CTE of the clamp material. Finally clamp dimensional changes are taken into account. This is achieved directly by subtracting a prerecorded baseline from the measurements; or by determining the CTE measurement for various sample lengths and obtaining the slope of a straight line through the points on a MD (measured displacement)/DT (temperature range of displacement measurement) versus sample length plot. The slope is the corrected CTE.

Abstract: A modular materials characterization apparatus includes a sensor array disposed on a substrate, with a standardized array and contact pad format; electronic test and measurement apparatus for sending electrical signals to and receiving electrical signals from the sensor array; an apparatus for making electrical contact to the sensors in the standardized array format; an apparatus for routing signals between one or more selected sensors and the electronic test and measurement apparatus and a computer including a computer readable having a computer program recorded therein for controlling the operator of the apparatus. The sensor array is preferably arranged in a standardized format used in combinatorial chemistry applications for rapid deposition of sample materials on the sensor array.

Abstract: Methods and devices for improved measurement of the thermal expansion and/or chemical reactivity of aggregates used in concrete and for similar substances. Aggregate is placed into the chamber of a metallic container having an enlarged opening. The aggregate is placed in a water bath, and a tightly sealable lid is placed onto the container. The lid carries a linear variable differential transducer (LVDT). A thermocouple for sensing temperature is also retained within the lid so that a sensor on the thermocouple contacts the water bath when the lid is secured onto the container. The LVDT is operationally interconnected with a storage or recording device. In a preferred construction the lid retains a tower member having a float that is freely moveably mounted upon a guide rod. Movement of the float is indicative of a volumetric change in the aggregate and water.

Abstract: A method for determining the Coefficient of Thermal Expansion of a specimen. The specimen is placed in the tester and a tensile force is applied to the specimen. The specimen is equilibrated at a first temperature and then elongated. After reaching a desired elongation, the specimen is equilibrated at another temperature. The tensile force on the specimen is changed to a predetermined value or until the specimen fails. A force-displacement curve is generated from the stressed specimen. The force-displacement curve is converted into a stress-strain response, from which the Coefficient of Thermal Expansion is determined.

Abstract: An instrument for determining thermophysical properties of a solid sample of uniform thickness is disclosed. The instrument comprises a furnace, an elliptical mirror outside the furnace, a light source at one focus of the elliptical mirror that is closest to the elliptical mirror, a beam guide having one end at the other focus of the elliptical mirror and the other end inside the furnace, a sample holder inside the furnace capable of holding at least two diffusivity samples with the front and back surface of a sample exposed, an indexing system for moving the sample holder so as to place samples held by the sample holder in the path of light leaving the beam guide, and an infrared detector for quantifying changes in the temperature of the back surface of a sample that is in the path of the light. Methods for determining the thermal diffusivity, specific heat capacity, thermal conductivity, coefficient of thermal expansion, density, and temperature of a sample using this instrument are also disclosed.

Abstract: Methods and devices for improved measurement of the thermal expansion and/or chemical reactivity of aggregates used in concrete and for similar substances. Aggregate is placed into the chamber of a metallic container having an enlarged opening. The aggregate is placed in a water bath, and a tightly sealable lid is placed onto the container. The lid carries a linear variable differential transducer (LVDT). A thermocouple for sensing temperature is also retained within the lid so that a sensor on the thermocouple contacts the water bath when the lid is secured onto the container. The LVDT is operationally interconnected with a storage or recording device. In a preferred construction the lid retains a tower member having a float that is freely moveably mounted upon a guide rod. Movement of the float is indicative of a volumetric change in the aggregate and water.

Abstract: A method for estimating the thermal displacement of a rotatable component of a machine tool is provided which includes the steps of: (A) generating a signal representative of the temperature of at least one rotatable component of a machine tool, the component being rotatable having a variable rotational speed and a variable temperature; (B) converting the signal representative of the temperature into a numerical value; and (C) estimating the thermal displacement of the rotatable component based on the numerical value using an operational expression. In this method, the operational expression includes a coefficient which is a function (f(n)) that changes with time or the number(n) of compensation operations performed, with the function (f(n)) determined by a relational expression T(N)) relating the time constant (T .delta.) of the thermal displacement and the rotational speed (N) of the rotatable component.

Abstract: By employing a "modulated-temperature" heating program composed of a series of heat-isotherm stages, it is possible to separate the change in dimensions of an oriented material during heating into two contributions: a thermally "reversing" component which is due to linear thermal expansion and a "non-reversing" part arising from relaxation to the disordered state on heating above T.sub.g. Some preliminary results for biaxially drawn poly(ethylene terephthalate) film are presented.

Abstract: A thermomechanical analyzer capable of performing, in addition to thermomechanical measurement, thermogravimetry of a sample of several grams or more only by switching parts of the analyzer. A thermomechanical analyzer has a heating furnace, a temperature detector for detecting temperature of the sample that is placed within the heating furnace, an attachable/detachable detecting rod and a sample holding member, wherein the sample is held between the detecting rod and the sample holding member. A load applying instrument applies an external force to the sample via the detecting rod. A displacement detector detects displacement of the detecting rod relative to the sample holding member. The thermomechanical analyzer is provided with a control computing apparatus for adjusting an output from the load applying instrument to bring an output from the displacement detector closer to a fixed value.

Abstract: A plurality of fatigue life test strips (16, 18, 20, 22) has each of the strips anchored to a base (12) which is subject to thermal cycling and consequent dimensional change which causes fatigue. The base is, at best, semiconductive, and the strips are conductive. The conductivity of each of the strips is measured by test circuit (52) so that, when one fails due to fatiguing, the failure is signaled.

Abstract: A device for measuring the thermal expansion of a sample comprises a measurement radiation generator, a base member incorporating a reference groove and a furnace. The furnace has an external reference contour adapted to cooperate with the reference groove, an internal reference contour adapted to cooperate with a sample and an aperture through which the measurement radiation passes.

Abstract: A capillary rheometer apparatus includes a housing, a plunger, the housing having a reservoir for receiving the plunger in a polymer melt, and a mechanism for blocking flow of the melt out of the reservoir. A driving mechanism is included for driving the plunger longitudinally within the reservoir to move one end of the plunger in contact with the melt. A diaphragm, which is coupled to the one end of the plunger, deflects in response to melt pressure in the reservoir. A mechanism, responsive to diaphragm deflection, determines pressure of the melt. Another mechanism is included for determining the temperature of the melt and a further mechanism is included for indicating longitudinal movement of the plunger. From such determinations, the PVT characteristics and the apparent shear viscosity characteristics of the polymer melt can be obtained.

Abstract: A thermally stable fixture for testing asphalt samples is characterized by easurements of both thermal stresses and strains in the sample. The device uses air as the sample cooling or heating fluid for inducing thermal stresses and strains therein. Strains are detected by a linear variable differential transformer mounted on the sample suspended within the fixture. Stresses are detected by a load cell connected with a mounting plate for the sample. Temperatures are detected by temperature sensors attached to the sample and to the fixture for measuring sample and ambient air temperatures, respectively.

Abstract: An apparatus for measuring and monitoring a change in the dimension of a sample being heated by microwave energy is described. The apparatus comprises a microwave heating device for heating a sample by microwave energy, a microwave compatible dilatometer for measuring and monitoring a change in the dimension of the sample being heated by microwave energy without leaking microwaves out of the microwave heating device, and a temperature determination device for measuring and monitoring the temperature of the sample being heated by microwave energy.

Abstract: An apparatus and method are described for maintaining a constant temperature across an electrically conductive specimen required to be mechanically tested. The invention includes resistance heating the specimen to a desired level during mechanical testing. The specimen is also simultaneously induction heated to a desired level. The resistance heating and inductive heating cooperate so as to heat the specimen to a desired substantially constant temperature during mechanical testing.

Abstract: A device and method for measuring the deformations of a sample, which deformations particularly result from the relaxation of the stresses to which the samples was previously subjected. The device and method include the use of a cell inside which the sample is placed with the cell containing a thermal mass whose heat capacity and/or thermal conductibility are appreciably greater than those of air under normal temperature and pressure conditions.

Abstract: A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

Abstract: An improved dilatometer suitable for testing the coefficient of thermal expansion (CTE) of a workpiece. The workpiece having a CTE in the range of -0.2.times.10.sup.-6 inch/inch .degree.F. to 0.2.times.10.sup.-6 inch/inch/.degree.F. The improvement includes a reference structure means for positioning and isolating the workpiece, and for maintaining an independent reference temperature, uninfluenced by a required workpiece temperature differential. The temperature independent reference structure means helps assure that measurements of expansions/contractions of the workpiece, as a function of temperature, are uniquely that of the workpiece, and not that of the reference structure means, or any other ambient temperature determinant. The improved dilatometer is particularly useful for determining the CTE of a workpiece having a relatively low value, e.g., a CTE less than 0.1.times.10.sup.-6 inch/inch .degree.F.

Abstract: A thermomechanical analysis apparatus includes a probe assembly supported in substantially weightless contact with a sample material over a range of displacement of the probe by means of a linear motor controlled from a constant current source. The probe assembly is automatically weighed by measuring and storing the value of the current needed to raise the probe, that value is thereafter employed during the analysis mode to maintain the probe assembly in a substantially weightless condition.

Abstract: In a process for measuring the variations in volume, especially shrinkage measurements in duroplastics during the hardening, the material to be measured is acted upon by such a pressure that a fully homogeneous test piece is obtained without any fractures or blisters. Simultaneously and independently from one another, the impinging pressure, the pressure exerted through the test piece on the floor, the temperature in the test piece and in its environs and the volume of the test piece are measured under non-isothermal conditions and fed into a digital unit.

Abstract: Low temperature dilatometers are described which employ a combination cryostat/furnace made from an elongated block of metal by drilling separate longitudinal tubular chambers for insertion of a specimen tube containing a specimen and at least one electric resistance heater. A separate longitudinally drilled tubular cooling chamber serves as the expansion chamber for a conventional compressed gas refrigeration system, one end of the cooling chamber communicating with the inlet of the refrigerant gas compressor and the other end communicating, through an intermediate heat exchanger, with the outlet of the compressor. The metal construction of the cryostat/furnace and the absence of a conventional ceramic protection tube for the specimen facilitates rapid heat transfer to and from the specimen. The specimen can be brought quickly to the minimum desired temperature by operating the refrigeration system until that temperature is reached and then shutting off the compressor.

Abstract: Deformation dilatometers are described for heating, deforming and cooling a test specimen, as well as for measuring changes in the linear dimensions of that specimen. A ferrous metal specimen, that is held between a fixed and a movable fused silica or quartz platen, first is heated by a high frequency induction coil and then crushed by the application of a hydraulic force to the movable platen. The hydraulic force then is withdrawn and, as the specimen is cooled by a jet of quenching gas, changes in its linear dimension are measured by a linear variable differential transformer which is coupled through ceramic pushrods to the platens. Use of fused silica or quartz platens in deformation dilatometers permits the accurate simulation of steel mill forging and rolling operations and enhances the usefulness of the instruments for studying phase changes in steel and determining optimum heating and quenching rates.

Abstract: Low temperature dilatometers are described which employ a combination cryostat/furnace made from an elongated block of metal by drilling separate longitudinal tubular chambers for insertion of a specimen tube containing a specimen and at least one electric resistance heater. A separate longitudinally drilled tubular cooling chamber serves as the expansion chamber for a conventional compressed gas refrigeration system, one end of the cooling chamber communicating with the inlet of the refrigerant gas compressor and the other end communicating, through an intermediate heat exchanger, with the outlet of the compressor. The metal construction of the cryostat/furnace and the absence of a conventional ceramic protection tube for the specimen facilitates rapid heat transfer to and from the specimen. The specimen can be brought quickly to the minimum desired temperature by operating the refrigeration system until that temperature is reached and then shutting off the compressor.

Abstract: Dilatometers are described which employ measuring heads having multiple linear variable differential transformer dilation sensors for concurrently measuring the thermal dilation of multiple specimens within a single conventional electric tube furnace. The sensors, which have their cores coupled to calibrating micrometers, are positioned in a closely separated cluster in which each sensor is parallel, abreast and adjacent to each other. Separate parallel pushrods, which abut separate specimens within a common tubular specimen holder, are attached to the axially mobile coil of each sensor at the point closest to the center of the cluster. The resulting close separation of the parallel pushrods and their specimens within a small diameter specimen holder permits the use of an energy efficient electric tube furnace having a small diameter oriface and facilitates uniform heating of the pushrods and specimens.

Abstract: Differential dilatometers are described which employ a linear variable differential transformer dilation sensor in which the core and/or coil is independently supported to accommodate the imposition of a constant load on a specimen abutting a pushrod coupled to that transformer element. The independent support system has at least one collar that slidably enages a mating extension of the supported transformer element, thereby permitting long range axial movement of that element while rigidly restricting lateral movement. The collar which thus holds the supported transformer element may be tilted by an adjustable clamp on at least one plant parallel to the path of axial movement of that element, thereby facilitating alignment adjustment.

Abstract: A specimen testing apparatus is disclosed, including a sensing device for engaging a specimen mounted on a support, an electrical measuring system associated with the sensing device for producing an electrical signal that is a function of a variation in a physical characteristic of the specimen as determined by the sensing device, and an electromagnetic compensation system for applying a compensating force to the sensing device. In one operating condition (as, for example, when the thermal expansion properties of the specimen are being tested), the compensation system is operable to apply to the sensing device a force compensating for the weight of the sensing device, thereby to cause the sensing device to rest upon the specimen in a weightless force-free manner. Alternately, the compensation system may be operable to apply to the sensing device a supplemental force in the compressive stressing condition, as might be desired when penetration tests are to be conducted on the specimen.

Abstract: A differential dilatometer for simultaneously measuring the relative expansion of two different solid test samples, one of which can be a reference sample. The test sample and the reference are mounted in a support tube and suspended from a head, and the variation in length of the samples is transferred by two push rods connected respectively to the coil and core of a differential transformer. The support tube is inside a cryostat to permit circulation of a cryogenic fluid, during measurements. An electric heating sleeve inside the cryostat provides for further temperature regulation. Both the push rods and the support tube are of vitreous silica. The heating sleeve is supported by the head via thermal insulation, and the head is supported by a vibration absorbing mount.