The potential for iron and copper based rapidly solidified alloys as fusion reactor materials

Abstract

Rapid quenching from the melt, a new, rapidly evolving field of effort, is revolutionizing alloy design, compositions, processing and the resultant properties. Low alloy segregation (zero for the glassy state), unusual grain size control, down to submicron sizes, sharply increased solid state supersaturation (even of insoluble elements), and controlled size, shape and distribution of excess phases make possible broad control of structure and therefore of properties. Of particular interest as fusion reactor materials are copper alloys and ferritic steels, in part because of excellent thermal conductivity relative to most other alloy systems. Ability to select alloying elements to take into account requirements for activation; useful strength levels up to 400 or 500°C, including thermal stresses; swelling resistance; long term structural stability with increasing temperature are discussed. Strengthening by elemental precipitation, by intermetallic compounds, fine refractory oxides and combinations of these are demonstrated.