Thermal Expansion Match Between Molybdenum (Tzm Alloy) and Oxides of the Perovskite and Spinel Types.
Ceram Bull 1976 Mar; 55(3):281-284
The Bureau of Mines made thermal expansion measurements to 1,200 deg c on a wide selection of complex oxides of both the perovskite and spinel structures. These are compared to the thermal expansion of molybdenum and the molybdenum alloy tzm to find suitable expansion matches for oxide coating development. A dilatometric technique was employed which makes use of a measuring microscope accurate to 5 x 10-5. In general, the spinels display a closer expansion match with the metal than the perovskites. Magnesium orthochromite showed the closest match between 25 deg and 1,000 deg c. Its expansion in this range is 13 pct greater than that of molybdenum and tzm. Of the 50 oxide compositions examined, only 12 had expansion coefficients within 20 pct of that of molybdenum. All of these were orthochromites except the perovskite, 3bahfo3.Bazro3.
Ceram. Bull., V. 55, No. 3, March 1976, PP. 281-284