Development of a UK national standard for the thermal properties of molten materials: thermal diffusivity of molten copper

As part of a project to establish a UK national standard apparatus for measurement of the thermal diffusivity/conductivity of molten materials, thermal diffusivity measurements have been made on a copper candidate reference material. In this paper we comment generally on some potential reference materials for the metallurgical and polymer processing industries and present measurements of the thermal diffusivity of molten copper from the melting point up to 1200 °C obtained with a laser-flash apparatus. The results have an expanded uncertainty of ′11.7%, based on a combined uncertainty of ′4.76 multiplied by a coverage factor of 2.45, providing a level of confidence of approximately 95%. Plans are described for imminent work on other materials including tin, lead, and polyethylene.