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Temperature is a critical aspect in the control of processes in engineering. The measurement, however, must take into account not only the accuracy of the sensor but also the implementation costs and uncertainty. Thermocouples are one of the most widely used temperature measurement methods combining low costs, high measurement ranges, and relatively good accuracy. The acquisition system, however, is usually expensive. This paper evaluated the uncertainty in the temperature measurements of a K-type thermocouple using low cost Arduino® compatible hardware as a data acquisition system. This set was calibrated using a thermostatic distilled water bath at both freezing and boiling phase change points. The equations for uncertainty calculation were fully developed, and the procedures described serve as a reference for uncertainty assessment for thermocouples with other data acquisition systems. Although the calibration was the most significant contributor, the low variability of measurements shows the system has good stability and is a fine choice for industrial applications. The calculations are easy to implement as a routine for several measurements and guarantee results up to the international reference standard.

With technological advances, polymers are increasingly used to manufacture various components that were previously exclusively manufactured with metals. One of the significant challenges in polymer processing is its relatively low thermal resistance, since relatively small temperature variations, especially when compared to metals and ceramics, lead to significant changes in material properties and in the final component geometry. This paper investigated how the internal temperature of polymers, subjected to an intermittent particulate jet deposition process in conjunction with a continuous flow of hot air, is affected by variation in surface roughness, polymer type, and air pressure. As the main result, low efficiency in heat transfer was caused by the combination of the convective nature of the heat exchange with the low thermal conductivity of the polymers. The variables with the most significant influence on the process were the intermittence and pressure of the particulate jet.

The combination of relatively low production costs and a versatility makepolymers one of the most used classes of engineering materials. Thecomplexity of their chemical bounds, however, make the thermomechanicalprocessing of these materials a challenge since thermal flux frommanufacturing might significantly alter their properties. In this paper wasevaluated the use of thermocouple with Arduino® compatible hardware formeasurement and control of an intermittent heating system for processing ofNylon-6 and polycarbonate thermoplastics. A 2² factorial design was createdfor using K-type thermocouple for the two polymers at two different surfacefinishes obtained by sanding with mesh #80 and #600 abrasives. The resultsindicate that the Arduino interface has satisfactory processing capacity formonitoring heating cycles and temperature logging, making it possible toknow how temperature variated and at what level it stabilized for the heatingconditions presented. The difference in material specific heat capacity andthermal conductivity will affect the observed temperature profile. Roughnessmight present a considerable effect on the material heating since it is linkedto the heat exchange area of the process.