List of thermal conductivities

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In physics, thermal conductivity, k, is the intensive property of a material that indicates its ability to conduct heat.

First, we define heat conduction by the formula:

$H=\frac{\Delta Q}{\Delta t}=k\times A\times\frac{\Delta T}{x}$

where $\frac{\Delta Q}{\Delta t}$ is the rate of heat flow, k is the thermal conductivity, A is the total surface area of conducting surface, ΔT is temperature difference and x is the thickness of conducting surface separating the 2 temperatures.

Thus, rearranging the equation gives thermal conductivity,

$k=\frac{\Delta Q}{\Delta t}\times\frac{1}{A}\times\frac{x}{\Delta T}$

(Note: $\frac{\Delta T}{x}$ is the temperature gradient)

This list makes up the data for the smaller list provided in Thermal conductivity.

Please note that mixtures may have variable thermal conductivities due to its composition.

Material	Thermal conductivity (W·m⁻¹·K⁻¹)	Temperature (K)	Electrical conductivity @ 293 K (Ω⁻¹·m⁻¹)	Notes
Air	0.024^d - 0.025^e - 0.0262^a	273^d - 293^e - 300^a	3.333 × 10^-6^[1]	(N+21%O+0.93%Ar+0.04%CO₂) (1 atm)
Alcohols OR Oils	0.1^e - 0.21^e	293^e
Aluminium, pure	205^d - 220^f - 237^egi	293^egi	37.45^g - 37.74ⁱ × 10⁶
Aluminium nitride	170^m
Alumina, pure	40^[2]	293
Beryllium oxide	218^m
Brass Cu63%	125^g	296^g	12.82^g - 21.74^g × 10⁶	(Cu63%,Zn37%)
Brass Cu70%	109 ~ 121^g	296^g	12.82^g - 21.74^g × 10⁶	(Cu70%,Zn30%)
Bronze	26^f 42 ~ 50^g	296^g	5.882^g - 7.143^g × 10⁶	Sn25% (Cu89%,Sn11%)^f
Cast iron	55^f			(Fe+(2-4)%C+(1-3)%Si)
Carbon steel	36^f - 50.2^d - 54^f			(Fe+(1.5-0.5)%C)
Concrete	0.8^d - 1.28^e	293^e		~61-67%CaO
Copper, pure	386.0^z 368.7 353.1	279^z 559 859	59.17^g - 59.59ⁱ × 10⁶	IACS pure =1.7×10^-8Ω•m =58.82×10⁶Ω^-1•m^-1
Cork	0.04^d - 0.07^e	293^e
Diamond, pure synthetic	2000ⁱ-2500ⁱ	293ⁱ	(Lateral)10⁻¹⁶ ⁱ - (Ballistic)10⁸⁺ ⁱ	(>99.9%¹²C)
Diamond, impure	1000^ad	273^a ~ 293^d	~10⁻¹⁶ ⁱ	Type I (98.1% of Gem Diamonds) (C+0.1%N)
Expanded polystyrene	0.033^ad - ((PS Only)0.1 - 0.13^g)	98^a-298^a-296^g	<10⁻¹⁴ ^g - 10⁰ ^g	(PS+Air+CO₂+C_nH_2n+x)
Fiberglass OR Foam OR Wool	0.03^e - 0.04^d - 0.045^e	293^e
Glass	0.8^d−0.93^e((96%SiO₂)1.2-1.4^g)	293^eg	10⁻¹⁴ - 10⁻¹² ^g - 10⁻¹⁰	<1% Iron oxides
Glycerol	0.29^e	293^e
Gold, pure	314^d - 318^fgi	300^gi	45.17ⁱ - 45.45^g × 10⁶
Granite	1.73^b - 3.98^b			(72%SiO₂+14%Al₂O₃+4%K₂O etc.)
Ice	1.6^d - 2.1^e - 2.2^a	293^e - 273^a
Iron, pure	71.8^f - 79.5^d - 80.2^a - 80.4^gi	300^agi	9.901^g - 10.41ⁱ × 10⁶
Marble	2.07^b - 2.94^b			Mostly CaCO₃
Limestone	1.26^b - 1.33^b			Mostly CaCO₃
Lead, pure	34.7^d 35.0^f 35.3^gi	293^d ^f 300^gi	4.808ⁱ - 4.854^g × 10⁶
Nitrogen, pure	0.0234^d - 0.02583ⁱ - 0.026^a	293^d - 300^ai		(N₂) (1 atm)
Oxygen, pure	0.0238^d - 0.02658ⁱ	293^d - 300ⁱ		(O₂) (1 atm)
Plastic, fiber-reinforced	0.23^g - 0.7^g - 1.06^e	296^g - 293^e	10⁻¹⁵ ^g - 10⁰ ^g	10-40%GF or CF
Polymer, High-Density	0.33^g - 0.52^g	296^g	10⁻¹⁶ ^g - 10² ^g
Polymer, Low-density	0.04^g - 0.16^e - 0.25^e - 0.33^g	296^g - 293^e	10⁻¹⁷ ^g - 10⁰ ^g
Rubber (92%)	0.16^a	303^a	~10⁻¹³
Sandstone	1.83^b - 2.90^b			~95-71%SiO₂
Snow, dry	0.11^d
Silica Aerogel	0.003^a-0.004ⁱ-0.008^k-0.017^k-0.03ⁱ	98^a - 298^a		Foamed Glass
Silicon dioxide, pure	1^m
Silver, pure	406^d - 418^f - 429^agi	300^agi	61.35^g - 63.01ⁱ × 10⁶	Highest electrical conductivity of any metal
Soil	0.17^c - 1.13^c			composition may vary
Stainless steel	16.3^g	296^g	1.389^g - 1.429^g × 10⁶	AISI 302(Fe,Cr18%,Ni8%)
Steel(normal)	50.2^d	293^d
Titanium, pure	15.6^f - 21.9^gi	300^gi	1.852^g - 2.381ⁱ × 10⁶
Titanium Alloy	5.8^g	296^g	0.595^g × 10⁶	(Ti+6%Al+4%V)
Thermal grease, silver-based	2ⁱ - 3ⁱ
Water	0.6^de	293^de	5×(Pure)10⁻⁶ ⁱ -(Sweet)10^−3±1 ⁱ -(Sea)1ⁱ	<3%(NaCl+MgCl₂+CaCl₂)
Wood, +>=12% water	0.09091^h - 0.16^a - 0.21^h - 0.4^e	298^a - 293^e		Species-Variable^h
Wood, oven-dry	0.04^d - 0.07692^h - 0.12^d - 0.17^h			Cedar^h - Hickory^h
Zinc oxide	21^m
Material	Thermal conductivity (W·m⁻¹·K⁻¹)	Temperature (K)	Electrical conductivity @ 293 K (Ω⁻¹·m⁻¹)	Notes

[edit] References

^a CRC handbook of chemistry and physics (subscription is required to access the data)

^b Marble Institute of America (2 values are usually given: the highest and lowest test scores)

^c Soil Sci Journals

^d HyperPhysics, also from Young, Hugh D., University Physics, 7th Ed. Table 15-5. (data from HyperPhysics should be all at 20^oC)

^e Hukseflux Thermal Sensors

^f Engineers Edge

^g GoodFellow

^h Physical Properties and Moisture Relations of Wood

ⁱ Other listings within Wikipedia references (this table may not be cited, pure elements are sourced from Chemical elements data references, otherwise an in-table linked-page must list the relevant references)

^j Clarity requires that no reference is to use this letter

^k Thermal Properties - Silica Aerogels

^l [1] Machinery's Handbook - properties of materials p404]

^m Greg Becker, Chris Lee, and Zuchen Lin (Jul 2005). "Thermal conductivity in advanced chips — Emerging generation of thermal greases offers advantages". Advanced Packaging: pp.2–4.

^z EngineeringToolbox.com

Heat Conduction Calculator

Thermal conductivity of air as a function of temperature can be found at James Ierardi's Fire Protection Engineering Site