ABSTRACT
Under a Phase I Small Business Innovative Research contract from the National Institute of Standards and Technology (NIST), we are designing a subminiature guarded hot plate apparatus that can be used to determine the thermal conductivity or thermal resistance of very small specimens (1 to 3 cm square) of thermal insulation materials over a temperature range of (at least) −40 °C to +100 °C, with the capability to carry out measurements in air, selected gases, or vacuum. In this paper, we present the performance criteria and specifications for the apparatus, alternative measurement approaches that were reviewed, the overall design approach that was selected, and the current stage of development of the detailed design of the prototype apparatus to be built during Phase II of this contract. The apparatus to be developed under this project will be of direct value to manufacturers of insulation materials and polymers, particularly for use in characterizing experimental products that are only available in very small sample sizes.
