Processing of CP-Ti by high-pressure torsion and the effect of surface modification using a post-HPT laser treatment

Abstract

Commercial purity titanium (CP-Ti) was processed by high-pressure torsion (HPT) with various numbers of turns (N = 1, 10 and 20). The hardness of the CP-Ti increased with an increasing number of HPT turns due to grain refinement. Tensile testing showed that the PT-processed 10 turns sample had low ductility and high strength but the ductility may be improved through post-HPT short-term annealing at carefully selected temperatures. Some HPT-processed samples were laser surface-treated with different laser powers and scanning speeds.
The surface roughness of the laser-textured samples increased with increasing laser power and led to a lower contact angle which signifies an increased hydrophilicity. After a holding time of 13 days, the samples underwent a hydrophilic-to-hydrophobic transformation as the contact angle increased
to as much as 129 degree. It is concluded that laser surface texture processes are capable of controlling the hydrophilic / hydrophobic properties of ultra-fine grained CP-Ti.

More information

Identifiers

ORCID for Yi Huang: orcid.org/0000-0001-9259-8123

ORCID for Terence G Langdon: orcid.org/0000-0003-3541-9250

Catalogue record

Export record

Altmetrics