| Abstract |
Electronics assemblies generate waste heat. Emphasis on size, cost, and manufacturing technique leads
design engineers to use elegant thermal interface solutions between waste heat generating components
and heat sinks. Our industry needs to describe alternate thermal interface materials in a more complete
and standardized way. Suppliers have cooperated in development of standard test methods for interface
materials.
The United States Defense General Supply Center, Richmond Virginia, invited ASTM (American Society
for Testing and Materials) and domestic United States thermal interface materials suppliers to participate
in development of industrial standards to replace Military standards for thermal interface materials and
parts. Existing standards were Mil I 49456A and Mil I 49466. ASTM committee D-09-19 formed two
separate task groups. The intent was to generate thermal conductivity test methods and a composite set of
property test methods within the supervision and control of the Committee on Electrical and Electronic
Insulating Materials. One task group developed standard test methods to measure the thermal resistance
and thermal conductivity of thin, conformal thermal interface materials. A second task group agreed to a
composite set of test methods for the characterization of most properties of thin, flexible thermal interface
materials.
The first ASTM task group prepared test method ASTM D 5470-95. Method A of this standard borrows
from ASTM E 1225. It is appropriate to measure thin, conformable materials. ASTM D 5470 has
demonstrated good laboratory to laboratory correlation in a round robin test demonstration. The second
task group prepared ASTM D 6343-98 to collect test methods appropriate for characterization of thermal
interface materials.
A common set of test methods to measure the characteristics of competing materials has been established. |
