Fatigue performance of medical Ti6Al4V alloy after mechanical surface treatments

PLoS One. 2015 Mar 30;10(3):e0121963. doi: 10.1371/journal.pone.0121963. eCollection 2015.

Abstract

Mechanical surface treatments have a long history in traditional engineering disciplines, such as the automotive or aerospace industries. Today, they are widely applied to metal components to increase the mechanical performance of these. However, their application in the medical field is rather rare. The present study aims to compare the potential of relevant mechanical surface treatments on the high cycle fatigue (R = 0.1 for a maximum of 10 million cycles) performance of a Ti6Al4V standard alloy for orthopedic, spinal, dental and trauma surgical implants: shot peening, deep rolling, ultrasonic shot peening and laser shock peening. Hour-glass shaped Ti6Al4V specimens were treated and analyzed with regard to the material's microstructure, microhardness, residual stress depth profiles and the mechanical behavior during fatigue testing. All treatments introduced substantial compressive residual stresses and exhibited considerable potential for increasing fatigue performance from 10% to 17.2% after laser shock peening compared to non-treated samples. It is assumed that final mechanical surface treatments may also increase fretting wear resistance in the modular connection of total hip and knee replacements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alloys
  • Biocompatible Materials*
  • Compressive Strength
  • Equipment Failure Analysis
  • Humans
  • Materials Testing / instrumentation
  • Materials Testing / methods
  • Prostheses and Implants*
  • Prosthesis Failure
  • Stress, Mechanical
  • Surface Properties
  • Titanium*

Substances

  • Alloys
  • Biocompatible Materials
  • titanium alloy (TiAl6V4)
  • Titanium

Grants and funding

The work was funded through the Ministry of Art and Science of Baden-Württemberg, Germany. (RS JR JPK). The authors acknowledge financial support by Deutsche Forschungsgemeinschaft and Ruprecht-Karls-Universität Heidelberg within the funding programme Open Access Publishing. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.