Radiation effects in beryllium used for plasma protection

This paper reviews the literature on beryllium, emphasizing the effects of irradiation on essential properties. Swelling and embrittlement experiments as a function of irradiation temperature and dose, and as a function of neutron spectrum are described, and the results are quantified, where possible. Effects of impurity content are also reported, from which optimum composition specifications can be defined. Microstructural information has also been obtained to elucidate the processes controlling the property changes. The available information indicates that beryllium divertors can be expected to embrittle quickly and may need frequent replacement. ((orig.))