Penetration rate studies of stainless steel by molten uranium and uranium-fissium alloy

Abstract The rate of penetration of Type 304 stainless steel by molten uranium and uranium-5 wt % fissium alloy was investigated by a dip method in the range 1100 to 1350° C. For the uranium-5 wt % fissium alloy the rate was found to increase rapidly from 0.6 mils/sec ( 1.5 × 10 −3 cm/sec ) at 1100° C to 12 mils/sec ( 3 × 10 −2 cm/sec ) at 1150° C. It then sharply reversed, decreasing to 2.5 mils/sec ( 6.3 × 10 −3 cm/sec ) at 1187° C following which it gradually increased to 5 mils/sec ( 1.3 × 10 −2 cm/sec ) at 1350° C. Molten uranium was found to be somewhat more aggressive than molten uranium-5 wt % fissium alloy. The rates to penetrate 304 stainless steel were 15 mils/sec ( 3.8 × 10 −2 cm/sec ) at 1150° C, 4 mils/sec ( 1 × 10 −2 cm/sec ) at 1187° C and 6.5 mils/sec ( 1.65 × 10 −2 cm/sec at 1350° C. The unexpected reversal in penetration rate with temperature was attributed to the formation of an intermetallic compound which retards the reaction. It was found that surface film formation and phase transformation in the stainless steel were not the cause of this reversal.