Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising Magazine Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Anritsu Alliance Test Equipment Amplifier Solutions Anatech Electronics Axiom Test Equipment Berkeley Nucleonics Centric RF Conduct RF Copper Mountain Technologies Empower RF everything RF Exodus Advanced Communications Innovative Power Products ISOTEC KR Filters Lotus Systems PCB Directory Rigol San Francisco Circuits Reactel RFCT TotalTemp Technologies Triad RF Systems Windfreak Technologies Withwave LadyBug Technologies Wireless Telecom Group Sponsorship Rates RF Cafe Software Resources Vintage Magazines Thank you for visiting RF Cafe!
Anritsu Test Equipment - RF Cafe

Thermal Conductivity & Coefficient of Expansion
Thermal conductivity is the propensity for any material to transfer heat from one point to another. Of course for heat to "flow," it is necessary for a difference of temperature to exist within a continuous section of the material. Thermal conductivity is analogous to electrical conductivity. Similarly, thermal resistance is the inverse of thermal conductivity as electrical resistance is the inverse of electrical conductivity.

Coefficient of expansion is the rate at which a material will grow in length with an increase in temperature. Most material grow in a fairly linear fashion, particularly within a defined range of temperatures. A positive coefficient of expansion indicates that the material gets longer as its temperature increases. Most metals are like that. Ice is a well-known example of a negative coefficient of expansion, since it contracts in length with increasing temperature (in other words, ice expands as it gets colder).

Substance Thermal Conductivity

(W/cm·°C)

 Coefficient of

Thermal Expansion

(ppm/°C)

 Density

(g/cm3)

 Specific Thermal Conductivityb

(W/cm·°C)
Air (still) 0.0003      
Alumina 0.276      
Alumina (85%) 0.118      
Aluminum 2.165 0.23 2.7 0.81
Beryllia (99.5%) 1.969      
Beryllia (97%) 1.575      
Beryllia (95%) 1.161      
Beryllium 1.772      
Beryllium-Copper 1.063      
Boron Nitride 0.394      
Brass (70/30) 1.220      
Copper 3.937 0.17 8.9 0.45
Copper/Invc/Copper 1.64 0.084 8.4 .020
Copper/Mod/Copper 1.82 0.060 9.9 0.18
Copper/Mod-Cu/Copper 2.45-2.80 0.60-0.10 9.4 0.26-0.30
Diamond (room temp) 6.299      
Epoxy 0.002      
Epoxy (thermally conductive) 0.008      
FR-4  (G-10) 0.003      
GaAs 0.591      
Glass 0.008      
Gold 2.913      
Heatsink Compound 0.004      
Helium (liquid) 0.000307      
Invar 0.11 0.013 8.1 0.014
Iron 0.669      
Kovar 0.17 0.59 8.3 0.020
Lead 0.343      
Magnesium 1.575      
Mica 0.007      
Molybdenum 1.299      
Monel 0.197      
Mylar 0.002      
Nickel 0.906      
Nitrogen (liquid) 0.001411      
Phenolic 0.002      
Platinum 0.734      
Sapphire (a-axis) 0.32      
Sapphire (c-axis) 0.35      
Silicon (pure) 1.457      
Silicon (0.0025 Ω-cm) 1.457      
Silicon Carbide 0.90      
Silicon Dioxide (amorphous) 0.014      
Silicon Dioxide (quartz, a-axis) 0.059      
Silicon Dioxide (quartz, c-axis) 0.11      
Silicone Grease 0.002      
Silicone Rubber 0.002      
Silicon Nitride 0.16 - 0.33      
Silver 4.173      
Stainless Steel (321) 0.146      
Stainless Steel (410) 0.240      
Steel (low carbon) 0.669      
Teflon 0.002      
Tin 0.630      
Titanium 0.219 0.086 4.4 0.016
Tungsten 1.969      
Water 0.0055      
Zinc 1.024      
 

a: Approximate values from 0 °C to 100 °C

b: Thermal conductivity divided by specific gravity

    (introduced by Dr. Carl Zweben & K.A. Schmidt)

c: Invar

d: Molybdenum

Lotus Communication Systems Modular RF Component Building Blocks - RF Cafe
withwave microwave devices - RF Cafe
Innovative Power Products Passive RF Products - RF Cafe		 Windfreak Technologies Frequency Synthesizers - RF Cafe
everythingRF RF & Microwave Parts Database - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free
 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

Webmaster:

    Kirt Blattenberger,

    BSEE - KB3UON

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

AirplanesAndRockets.com