ABSTRACT
Titanium substrates were subjected to severe plastic deformation using surface
mechanical attrition treatment (SMAT) in a high energy ball mill. It is demonstrated
that different mechanical treatments influence the microstructural and mechanical
behaviour of the Ti-surface; moreover, solid state amorphization takes place.
Amorphization take place concurrently in the surface region, and successive
subdivision and amorphization finally result in the formation of well separated
nanocrystalline and amorphous phases in the near surface. The average grain size
of the nanocrystallites is about ~200 nm after 10 min of SMAT while ~18 nm after 20
min.
Surface mechanically treatment of Ti-substrates were characterized by the X-Ray
Diffraction (XRD) and scanning probe microscope (SPM) using atomic force
microscopy (AFM). The microhardness of the mechanically treated Ti-surfaces is
improved as a result of surface nanocrystallization.