Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

An evaluation was made of the performance of 74 helium-bonded uranium-plutonium carbide fuel elements that were irradiated in EBR-II at 38-96 kW/m to 2-12 at. percent burnup. Only 38 of these elements have completed postirradiation examination. The higher failure rate found in fuel elements which contained high-density (greater than 95 percent theoretical density) fuel than those which contained low-density (77-91 percent theoretical density) fuel was attributed to the limited ability of the high-density fuel to swell into the void space provided in the fuel element. Increasing cladding thickness and original fuel-cladding gap size were both found to influence the failure rates for elements containing low-density fuel. Lower cladding strain and higher fission-gas release were found in high-burnup fuel elements having smear densities of less than 81 percent. Fission-gas release was usually less than 5 percent for high-density fuel, but increased with burnup to a maximum of 37 percent in low-density fuel. Maximum carburization in elements attaining 5-10 at. percent burnup and clad in Types 304 or 316 stainless steel and Incoloy 800 ranged from 36-80 .mu.m and 38-52 .mu.m, respectively. Strontium and barium were the fission products most frequently found in contact with the cladding but no penetration of the cladding by uranium, plutonium, or fission products was observed.

Post-irradiation examination (PIE) is an indispensable step in the selection of new or improved research reactor fuel, and in the characterization and understanding of its in-core behaviour. This publication provides an introduction to PIE techniques. It describes a typical PIE process from intercycle inspections in the reactor pool or channel, to hot cell PIE, which is subdivided into non-destructive and destructive testing techniques with their typical output, advantages and drawbacks, and their applicability to understanding fuel irradiation behaviour. Much of the work presented in this publication originated from the research and development of new low enriched uranium research reactor fuels. Intended readers include research reactor operators, regulators and their technical support organizations, fuel developers and manufacturers, laboratory staff, and policy makers.