Structural, physical and chemical changes induced in metals and alloys exposed to high power ion beams

This review summarizes recent experimental results on metals and alloys irradiated with high power ion beams (HPIB). It was revealed that the thickness of modified layers exceeded the projected ion range by more than two orders of magnitude. The surfaces of irradiated metals exhibit increased microhardness, abrasive and cutting wear resistances. It has been also shown that corrosion resistance increased in HPIB irradiated steels. The total modified layer (100 to 180 μm) may be conventionally divided into three regions which differ in types of defects and residual stresses. A model of HPIB interaction with metals and ion mixing in single- and multilayered structures has been considered. The HPIB modified layer is characterized by the formation of solid solutions, Cu₃Au, CuAu, and metastable states as well as more complex compounds which cannot be produced under usual equilibrium conditions. Positron annihilation, Mössbauer spectroscopy, SIMS, Auger-electron spectroscopy, RBS/C, X-ray analysis and electron microscopy were used as analysis tools. Microhardness, abrasive and cutting wear resistances were also measured.