Influence of a Femtosecond Laser Surface Modification on the Fatigue Behavior of Ti-6Al-4V ELI Alloy

• Published in: Materials Research
• Main Authors: Alan dos Santos, Leonardo Contri Campanelli, Paulo Sergio Carvalho Pereira da Silva, Rui Vilar, Maria Amélia Martins de Almeida, Alexei Kuznetsov, Carlos Alberto Achete, Claudemiro Bolfarini
• Format: Article
• Language: English
• Published: Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol) 2019-07-01
• Subjects: Ti-6Al-4V ELI; surface modification; laser; femtosecond; fatigue
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392019000400204&tlng=en
• ISSN: 1516-1439

The objective of this investigation was to evaluate the influence of surface modification by femtosecond laser (with average fluence of 0.6 J/cm2 and scanning speed of 0.1 mm/s) on the fatigue resistance of Ti-6Al-4V ELI alloy. A significant reduction in the fatigue strength of the material modified by laser was observed. Residual tensile stresses generated during surface modification were negligible, presenting lower values than those found on the unmodified surface. Based on a recently developed and published prediction model, the reduction of the fatigue strength was ascribed to the surface roughness created during the laser treatment of the alloy. An evidence was that the fatigue crack nucleation occurred in the modified region, rather than at the edge of the rectangular specimens as in the untreated condition.