The large deformation phenomena of thermoplastic polyester elastomer (TPC) is important in product design. However, at times of large deformation in tensile testing of thermoplastic polyester elastomer (TPC), it is difficult to measure the true stress-true strain curve, while heating is also an issue. The purpose of this study is to develop a simple new method in which part of the constitutive rule is replaced by a parameter obtained from actual measurement, in order to examine the heat generation phenomenon of thermoplastic elastomers. In this study, we conduct tensile testing of thermoplastic elastomer under various tensile rate conditions, and we observe true strain using Digital Image Correlation (DIC). Furthermore, we directly investigate the relationship between true strain and temperature by observing simultaneous measurement strain and temperature by thermographic camera. We apply heat exchange efficiency β to know the relationship between mechanical properties and heat generation phenomenon from the macroscopic point of view. This method is constructed by the finite element method (FEM) and accurate heat exchange efficiency β obtained by using these measurements. We were able to quantitatively discuss the effect on true strain due to heat generation in the large deformation region. Moreover, we could discuss the impact of TPC heat radiation and heat exchange efficiency β . We confirmed the validity of this method by applying it to TPC.

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The machine screws are used for a lot of manufacturing products. A lot of researches have been carried out on the self-loosening of bolt nut joints under transverse vibration However, few investigations have ever been carried out on self-loosening of machine screws . The purpose of this report is to obtain basic loosening characteristic information about this problem. This paper reports how the lubricant or the lacquer painting film influences self-loosening when the truss head machine screw is used. As a result, the bolted joint that painted the lacquer film bearing surface showed it was loose easily by the experiment. The reason that comes to loosen easily is that the lacquer painting film is stripped off by the vibration.

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Tensile tests are performed to composite materials containing various aspect ratios and orientation angles of fiber bundle in a plane. Their macroscopic elastic modulus is evaluated and it value is compared to the result obtained by micromechanical analysis to the composites. In analysis, the fiber bundle is modeled as a fiber with same diameter. Analytical results are good agreement with the center values in experimental ones irrespective of volume fraction of fiber bundle. However, scatter of the experimental results cannot explain by the analytical model. It is caused by the cluster effect of fiber bundle and macroscopic clustering of fiber bundles.

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Tensile tests are performed to composite materials containing various aspect ratios and orientation angles of fiber bundle in a plane. Their macroscopic elastic modulus is evaluated and it value is compared to the result obtained by micromechanical analysis to the composites. In analysis, the fiber bundle is modeled as a fiber with same diameter. Analytical results are good agreement with the center values in experimental ones irrespective of volume fraction of fiber bundle. However, scatter of the experimental results cannot explain by the analytical model. It is caused by the cluster effect of fiber bundle and macroscopic clustering of fiber bundles.

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Infrared thermometers to measure surface temperature have been increasingly adopted in recent years. The characteristics of the IR thermometer, however, are not well known.
IR thermometers manufactured in Japan systematically adjust for ambient radiation based on the internal temperature of the thermometer. If, therefore, there is a large difference between the internal temperature of the IR thermometer and the apparent temperature associated with the surrounding radiation, a large error will be induced into the measured surface temperature.
The purpose of our research was to determine the characteristics and measurement errors of IR thermometers. Experiments were performed with regard to the following items: (1) Measurement errors related to the internal temperature of the IR thermometer. (2) Linearity of the output signal of the IR thermometer. (3) Response of the output signal to changes in the emissivity setting. (4) Effect of sky radiant emittance on the measured surface temperature. (5) Calibration method for the terrestrial surface.
The following is a summary of the results: Measurement error is affected by the internal temperature of the IR thermometer. Measurement accuracy is improved with a controlled internal temperature of 20-30°C. The measurement error becomes larger at emissivity settings under 0.7.
The measurement error outdoors was not proportional to the downward longwave radiation, but to the sky radiant temperature measured by the IR thermometer. Calibration for sky radiant emittance was improved by using the difference between sky radiant temperature and air temperature.
When the surface temperature measured by the infrared thermometer is plotted against the surface temperature measured by thermocouple, the sky radiant emittance error is obtained from the Y intercept. Additionally, the difference between true temperature and output of the IR thermometer for a reference plate was compared to that obtained for vegetation, and the RMS obtained was about 1.0°C.

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