A SIMPLE APPARATUS FOR MEASURING ELECTRICAL-RESISTANCE OF MATERIALS AT HIGH-TEMPERATURES

Electrical resistance measurements in a wide temperature range are ver y important for understanding the physical properties of materials. It is often difficult to carry out the measurements at high temperatures since taking electrical leads reliably from specimens is a nontrivial problem. In this note we describe in detail a simple apparatus which can be used for studying any foil or pellet-shaped sample at temperatu res up to 800 degrees C in vacuum or in an inert atmosphere. The appar atus uses spring loaded pins for electrical contact, obviating the nee d for silver paint or spot welding, thus avoiding any possible change in the properties of the sample. The springs used for loading are far removed from the high temperature zone; the load, therefore, remains u nchanged during the experiment and the contacts remain uniformly relia ble. (C) 1996 American institute of Physics.