AMORPHOUS ALLOYS AND POSSIBILITIES FOR THEIR USE.

When metallic melts are cooled at very high rates (above 10**6 deg/sec), it is possible to preserve the liquid structure in the solid state. The thus-obtained alloys are called amorphous. The new alloys have anomalously high corrosion resistance. Moreover, the amorphous alloys can be passivated both under atmospheric conditions and in corrosive media. The possibilities for use of amorphous alloys depend completely on their tendency to undergo passivation. Results of an experimental program are presented in which production conditions, as well as properties and performance of amorphous alloys with different chemical compositions, have been studied. The results of the investigations showed that the amorphous alloys had high passivity and corrosion resistance only when they contained chromium. Alloys of composition FePC and FeB had approximately the same corrosion resistance as ordinary carbon steels. They were passivated spontaneously only in alkaline media. The corrosion behavior of alloy Fe//7//0Cr//1//0P//1//3C//7 was characterized by unique resistance to pitting corrosion. Pittings were not observed after tests with galvanostatic, galvanodynamic, and potentiostatic polarization and also after holding for 1000 h in solutions of NaCl (3%), FeCl//3 (6%), and HCl (1%). Economic considerations are included.