Platinum Metals Rev., 1967, 11, (3), 111
Differential Thermal Analysis in Platinum Equipment
Differential thermal analysis of volatile materials in contact with thermocouple junctions has hitherto proved impossible, but work by A. D. Russell at the Building Research Station (J. Sci. Instrum., 1967, 44, (5), 399) has now extended this technique to such samples by encapsulating them in a small platinum tube which, with a platinum wire welded to one end, forms one limb of the thermocouple, a 10 per cent rhodium-platinum wire forming the other limb. The reference junction containing an inert material is constructed similarly. Both junctions are protected by a platinum shield, and the alumina tubes carrying the thermocouple leads are sheathed in platinum. The apparatus has shown fast response and accurate results with calcium fluoride, which melts about 1413°C, and with volatile systems involving dicalcium silicate.