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Unit of thermal conductivity and CTE 2

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jasemty

Mechanical
Joined
Mar 4, 2003
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4
Location
HK
I find the units of thermal conductivity and CTE are 'ppm', how can I convert if to W/mC and um/m/C?

Thank you very much.
 
Where did you find it? (and what is CTE?) I believe ppm is parts per million.
 
Thermal conductivity (SI units): Watts/meter/oK or simply W/m-K.

CTE, coefficient of thermal expansion (linear) is expressed as a fractional increment per oC (or oF). Since it is very small, often given in units 10-6/oC, which could be written as ppmlength/oC = um/m/C.
 
Dear quark: I find it in some spec. for adhesive.

Dear kenvlach: Thanks for you help. How about the thermal conductivity? I can't convert the unit "ppm" to "W/m-K" because thermal conductivity is not a ratio.
 
As Kenvlach rightly defined both are ratios as their units indicate:

Thermal conductivity is given in W /(m.K).
The linear coefficient of thermal expansion ppm/K, is given in
10-6m /(m.K) .

Although both have the same divisor, they are not interconvertible because they are different entities.
 
Thank all of you giving valuable help.
 
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