New Development in Determination of Metal Volume Thermal Expansion Measurement Using Hydrostatic Weighing System (HWS)

Abstract

Volume thermal expansion measurement of solid material is one of the most challenging issue in material industry especially when the size of the sample is large. The existing instruments such as dilatometer has a limitation to determine the volume thermal expansion due to various of samples sizes and shapes. In this study, a new and precise hydrostatic weighing system (HWS) has been proposed to fulfil various samples shapes and sizes in the volume thermal expansion determination. The performance of the developed HWS was tested and evaluated using several samples such as gold and tungsten. The volume thermal expansion of gold and tungsten rod measured using the HWS are 1.5×10-4 °C-1 and 7.7×10-5 °C-1 respectively with expanded uncertainty of 0.0003 °C-1. The results of the HWS measurement was verified and compared with dilatometer. The comparison results show En ? 1 indicated that the performance of the HWS is acceptable. Furthermore, it is cheaper than dilatometer with reasonable accuracy and traceable to SI unit.