Designer's Guide Results
The following is a list of materials, selected and ranked per your specification.

MaterialThermal Conductivity
CVD Silicon Carbide300 W/mK
Silicon156 W/mK
Aluminum Nitride100 - 180 W/mK
Silicon Carbide Reaction Bonded110 - 155 W/mK
Silicon Carbide Sintered71 - 130 W/mK
Boron Nitride1.9 - 160 W/mK
Boron Carbide33 - 92 W/mK
Sapphire46.0 W/mK
Titanium DiBoride25 - 63 W/mK
Tungsten Carbide42 W/mK
Reference Materials
Diamond2000 W/mK
Tool Steel25- 63 W/mK
Stainless Steel14.9 W/mK

All properties values are at room temperature unless otherwise noted. Engineering data are representative, and are not intended as absolute nor warrantable. Data shown is blended from multiple sources and therefore illustrates the marketplace. The relative rankings are approximate and are based on representative values if the particular material has a range of values for a given property.

Wikipedia Definition(s) :  Thermal Conductivity;

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