Materials Science Division third quarterly report for period ending June 15, 1975

Further progress in materials studies for coal gasification plants are reported. Slag corrosion tests of refractories at about 1445/sup 0/C with an oxygen and steam atmosphere for up to 1500 hours are reported. Twenty-four refractories have been tested for dimensional and chemical integrity. Protective ceramic coatings have been fabricated on metals by various methods and tested for corrosion and thermal shock resistance. Nondestructive testing involved radiographic examination, ultrasonic and acoustic emission measurements to study their potential for detecting cracks in refractories. Infrared scanning studies to locate hot spots on equipment continued. The further development of mathematical models for erosive and corrosive wear on ductile and brittle materials continued with emphasis on the effects of oblique impacts. A failure mode analysis was carried out on a failed thermocouple sheath and instrument tubes using electron microprobe analysis, energy-dispersive x-ray analysis, auger electron spectroscopy, chemical analysis, metallography, eddy current analysis, ultrasonic examination, etc. (LTN)