Analysis of the mechanical and physicochemical properties of Ti-6Al-4 V discs obtained by selective laser melting and subtractive manufacturing method

J Biomed Mater Res B Appl Biomater. 2021 Mar;109(3):420-427. doi: 10.1002/jbm.b.34710. Epub 2020 Aug 20.

Abstract

The surface properties of titanium and its alloys are commonly modified by different techniques, including additive manufacturing (AM), to improve the osseointegration of dental implants. The aim of this study was to evaluate and compare the wettability, topography, chemistry, and structure of titanium-aluminum-vanadium (Ti-6Al-4 V) discs fabricated by selective laser melting (SLM) and subtractive manufacturing (conventional machining). Three different groups were evaluated: selective laser melting (SLM); conventional machining with H3 PO4 + NaOH surface treatment (CM + ST); and conventional machining without surface treatment (CM), including analysis of wettability and roughness, morphological and chemical analyses by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), and structural characterization analysis by computed tomography (micro-CT), and X-ray diffraction (XRD). The results showed that SLM surface had higher roughness (9.09 ± 1.94 Ra; 51.93 ± 11.59 Rz; 11.03 ± 1.95 Sa) and lower wettability (103.23° ± 13) than CM (0.06 ± 0.01 Ra; 0.42 ± 0.078 Rz; 0.07 ± 0.01 Sa) (76.95° ± 4.18) and CM + ST (0.17 ± 0.38 Ra; 0.88 ± 0.15 Rz; 0.18 ± 0.04 Sa) (18.55° ± 6.47) (p < 0.05). SEM images also proved the higher roughness of SLM surface, and CM + ST discs showed a topography resembling a sponge, characteristic of the nanometric treatment applied. EDX and XRD found no differences between the different surfaces, and micro-CT demonstrated the solid characteristic of the SLM disc. Compared with conventional machining, the SLM technique resulted in higher roughness and lower wettability. Meanwhile, the chemical properties and structure of the titanium alloy was not altered by the technique.

Keywords: additive manufacturing; dental implants; laser sintering technology; surface properties; titanium alloy.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Alloys / chemistry*
  • Freezing
  • Lasers*
  • Materials Testing*
  • Surface Properties
  • Titanium / chemistry*

Substances

  • Alloys
  • titanium alloy (TiAl6V4)
  • Titanium