Thermophysical Properties Research Laboratory, Inc.
Phone : 765-463-1581
Traveling Microscope Expansion

The traveling microscope expansion device was set up at TPRL, Inc. for measuring the thermal expansion of materials too soft to be tested in the dual push-rod dilatometer such as thin films or layers which have little compressive strength and would bend. The device works best for high expansion materials.

To start an experiment, a sample at room temperature (T0) is marked with fiducial points, and the distance between them (L0) is measured with a microscope and caliper. The temperature of the sample is increased to a new level (TM). Once the temperature of the sample has stabilized and the sample length is no longer changing, measure the distance between the fiducial marks (LM) again. Continue this process until the desired maximum temperature is reached or the sample disintegrates.

Calculate the expansion according to the relation:

ΔLM/L0 = (LM-L0)/L0

The mean coefficient (α) can also be calculated as:


Thermophysical Properties Measured

Thermal Conductivity

Thermal Diffusivity

Specific Heat

Thermal Expansion

Electrical Resistivity


Thermal Gravimetric Analysis & Simultaneous Thermal Analysis


ASTM Methods

Sample Sizes & Definitions

Copyright 2011 TPRL, Inc.
3080 Kent Avenue
West Lafayette, IN 47906
Last updated 1/5/2012