NPL Initiatives in the Development of Thermal Properties Reference Materials

The present paper describes the status of a number of studies involving NPL which are directed towards development of iInternationally accepted reference materials to serve different requirements. These include: (1) thermal diffusivity and thermal conductivity measurements on candidate molten metal reference materials; (2) co-operative flash diffusivity measurements on glassy carbon, a dense fine grain alumina, and other ceramics; (3) iInter-European studies, one using different steady-state and transient methods to evaluate the properties of a high temperature ceramic and the other using the guarded hot plate method to produce a high temperature thermal insulation reference; (4) a six-laboratory European program to certify a replacement European thermal insulation reference material for use at room temperature; and (5) an iIntercomparison between standards organizations in five countries on the current reference materials supplied in each country or geographical area. Brief mention is made concerning other on-going and planned work together with recommendations for materials to address additional needs.