NETZSCH LFA 447 Nanoflash, Operating Instructions Manual

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Operating the Instrument
LFA 447
TM
01/09 J:\LFA447\CHAPTER4.doc
1
Operating the instrument
Principle
IR-detector
xenon flash tube
filter wheel
sample
P.C.
furnace
power
pulse
forming
network
signal
amplifier
software
printer
T
T
max
T
max
Figure 1: measuring principle LFA 447
The Nanoflash instrumentation can be used to measure the thermal diffusivity, specific heat and
thermal conductivity of metals, graphite, coatings, composites, ceramics, polymers and other
materials. The instrumentation includes sophisticated hardware and simple menu-driven
software to provide fast, accurate, and safe measurements. The Nanoflash works to the flash
method according international standards ASTM E-1461, DIM EN 821 and DIN 30905.
The temperature rise of the other side is measured as a function of time using an infrared
detector. A typical curve is shown in Figure 2.
The measurement of the thermal diffusivity a and
specific heat c
p
allows the calculation of the thermal conductivity
λ
, with an additional
measurement or knowledge of the bulk density
ρ
of the sample material as shown in equation
(1).
λ
(T) = a(T)
⋅ ρ
(T)
⋅
cp(T) (1)
where: T is the Temperature
λ
is the thermal conductivity
a is thermal diffusivity
ρ
is the bulk density
c
P
is the specific heat