A recording apparatus suitable for thermal and differential thermal analysis was developed. It can be used to obtain data for phase diagram investigations on small samples of rare metals and their alloys at temperatures up to 1500 C. The thermal analysis apparatus consists of a platinum wound resistance furnace with protective atmos phere provisions and a Pt/Pt 13% Rh thermo couple as sensor which feeds a one mV strip chart recorder. A bucking potentiometer used in series with the thermocouple permits a temperature reso lution of better than 0.5 C. For differential thermal analysis, an additional 100 microvolt strip chart recorder is used. The heating or cooling rate can be varied between 0.5 C/min and approximately 15 C/minute. The thermal analysis apparatus was calibrated at several fixed points and has an overall accuracy of =1.5 C. (Author).

The Fourth International Cryogenic Materials Conference (ICMC) was held in San Diego, California in conjunction with the Cryogenic Engineer ing Conference (CEC) on August 10-l4, 1981. The synergism produced by conducting the two conferences together remains very strong. In the ap pl1cation of cryogenic technology, materials continue to be a demanding challenge, and sometimes, an obstacle. The association of materials and cryogenic engineers increases their awareness of recent research in each other's fields and influences the course of future research. Many contributed to the success of the 1981 conference. J. W. Morris of the University of California--Berkeley was ICMC Conference Chairman. E. N. C. Dalder of Lawrence Livermore Laboratories was ICMC Structural Program Chairman; D. C. Larbalestier of the University of Wisconsin- Madison, and D. K. Finnemore of Iowa State University were Superconducting Materials Program Chairmen. Local arrangments were expertly coordinated by R. E. Tatro of General Dynamics--San Diego. The CEC Board, especia11y their conference chairman, T. M. Flynn, of the National Bureau of Stan dards, Boulder, contributed very substantia1ly to conference planning and implementation. All of their efforts provided the foundation of the largest CEC/ICMC ever. We thank the Office of Naval Research and the Office of Fusion Energy and Basic Energy Sciences of the Department of Energy for providing needed financial support for the conference. Fina11y, we especially thank M. Stieg, who prepared the papers for the new procedures and format used in this volume.