Under high energy impact contact loading, a turning on the weight loss-impa
ct cycle (W-L-N) curve has been found, which results from the formation of
nano-sized grains embedded in amorphous in the surface layers of Hadfield s
teel. As the impact energy increases, the wear rate, dW(L)/dN, first increa
ses then decreases. The nanostructure due to the accumulation of plastic de
formation is composed of nano-sized grains spanning 10 similar to 50 atoms
and amorphous structures.