Effects of some technological aspects on the fatigue strength of a cementless hip stem

M. Viceconti, A. Toni, A. Giunti

Research output: Contribution to journalArticle

Abstract

Four prototype cementless hip stems were tested following the ISO 7206 protocol for the assessment of the endurance properties and compared with a cast Cr-Co-Mo (ASTM F75) commercially available stem which was used as reference design. All the tested stems were similar in shape and size, but with some substantial differences. The first was made of forged Ti6Al4V alloy (ASTM F136). The second, made of the same material, featured a central hole intended to reduce the bending stiffness of the stem itself. The third was identical to the second but for a small tooling notch in one of the fillets of the hole. The fourth was similar to the first but had a coating of sintered titanium beads in the proximal part. All of these modifications were made to evaluate the effect of fatigue strength of intentional or unintentional features commonly found in commercial stems. The forged Ti6Al4V alloy was found to be substantially stronger than the cast ASTM F75 Cr-Co-Mo alloy. However, tooling notches or sintered coatings were found to dramatically reduce this strength. Thus, the Ti6Al4V alloy calls for an accurate design process, especially when complex shapes or sintered structures are required.

Original languageEnglish
Pages (from-to)875-881
Number of pages7
JournalJournal of Biomedical Materials Research
Volume29
Issue number7
DOIs
Publication statusPublished - Jul 1995

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Fatigue
Hip
Coatings
Titanium
Durability
Stiffness
Fatigue strength
titanium alloy (TiAl6V4)

ASJC Scopus subject areas

  • Biomedical Engineering
  • Biomaterials

Cite this

Effects of some technological aspects on the fatigue strength of a cementless hip stem. / Viceconti, M.; Toni, A.; Giunti, A.

In: Journal of Biomedical Materials Research, Vol. 29, No. 7, 07.1995, p. 875-881.

Research output: Contribution to journalArticle

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