Preface Status of Metallic Materials Development for Application in Advanced High-Temperature Gas-Cooled Reactors

Abstract

The first gas-cooled reactor power station was built at Calder Hall in the United Kingdom and began operation in 1956. In this Magnox reactor type, CO/sub 2/ was used as the coolant and natural metallic uranium as the fuel. Magnox power plants with a combined electrical rating in excess of 8000 MW are now running and have achieved over 500 reactor-yr of operation./sup 1/ The advanced gas-cooled reactor (AGR) was developed in the United Kingdom as an extension of the Magnox line, retaining CO/sub 2/ as the primary coolant, using enriched UO/sub 2/ fuel to allow an increase in coolant temperatures from 360 to 650/sup 0/C. At the present time, AGR systems with a combined electrical rating of almost 9000 MW are in operation or under construction./sup 2/ The high-temperature gas-cooled reactor (HTGR) represents a further development to increase coolant temperatures. The higher operating temperatures (<750/sup 0/C) require changes in the fuel/core design and the substitution of helium for CO/sub 2/ as the primary coolant. This leads to a more economical plant with a higher power density core and a low radioactive environment within the primary loop. The technological development of the system has proceeded steadily with regard to: development more » of fuel particles, which are coated with layers of ceramics to retain fission products use of an all-graphite core construction use of helium gas as a coolant. « less