Ultrasonic Burnishing of Titanium Alloys

Resumo

This paper presents research results concerning the influence of ultrasonic burnishing on the structure and mechanical properties of ultra-fine grain titanium alloys: commercial pure titanium BT1-0 and an over stoichiometric alloy with the shape memory Ti_49.3Ni_50.7. It was shown by the methods of optical microscopy and transmission electronic microscopy that in the surface layer of 20 μm thickness, the ultrasonic burnishing in coarse-grained titanium forms a nanostructure with a grain size of 100 nm, and it additionally decreases the size of crystals from 100 to 30 nm in the nanostructural titanium nickelide. The ultrasonic treatment of alloys greatly increases the strength and micro- and nanohardness of the surface layer, decreases the roughness, forms the gradient nanostructure, improves the lifetime, and expands the functionalities of the items.