Comparison of Fatigue Properties and Fatigue Crack Growth Rates of Various Implantable Metals

Abstract

The fatigue strength, effects of a notch on the fatigue strength, and fatigue crack growth rate of Ti-15Zr-4Nb-4Ta alloy were compared with those of other implantable metals. Zr, Nb, and Ta are important alloying elements for Ti alloys for attaining superior long-term corrosion resistance and biocompatibility. The highly biocompatible Ti-15Zr-4Nb-4Ta alloy exhibited an excellent balance between strength and ductility. Its notched tensile strength was much higher than that of a smooth specimen. The strength of 20% cold-worked commercially pure (C.P.) grade 4 Ti was close to that of Ti alloy. The tension-to-tension fatigue strength of an annealed Ti-15Zr-4Nb-4Ta rod at 107 cycles was approximately 740 MPa. The fatigue strength of this alloy was much improved by aging treatment after solution treatment. The fatigue strengths of C.P. grade 4 Ti and stainless steel were markedly improved by 20% cold working. The fatigue strength of Co-Cr-Mo alloy was markedly increased by hot forging. The notch fatigue strengths of 20% cold-worked C.P. grade 4 Ti, and annealed and aged Ti-15Zr-4Nb-4Ta, and annealed Ti-6Al-4V alloys were less than those of the smooth specimens. The fatigue crack growth rate of Ti-15Zr-4Nb-4Ta was the same as that of Ti-6Al-4V. The fatigue crack growth rate in 0.9% NaCl was the same as that in air. Stainless steel and Co-Cr-Mo-Ni-Fe alloy had a larger stress-intensity factor range (ΔK) than Ti alloy.

Bioactive coating as a surface modification technique for biocompatible metallic implants: a review

“…316L VM is another type of stainless steel with corrosion resistance properties that have been used for biomedical applications. Okazaki et al have studied the use of 20 metallic 316L SS to replace of charnels hip arthroplasty in the human body [6]. After 13 years of implantation, the release of metal ions at increased concentrations was observed in the body fluid.…”

Fatigue performance of additively manufactured meta-biomaterials: The effects of topology and material type

“…It would be interesting to extend the current study to other prevalent biocompatible materials as well as other promising unit cell types (see for examples [43]) to see which of the two factors of material type or topological design is more influential in determining the fatigue response of AM meta-biomaterials. showed fatigue strengths around 130% of yield stress [44], 99% of yield stress [45], and 127% of yield stress [46] at 10 cycles. In the same studies, fatigue strengths around 124% of yield stress [45] and 150% of yield stress [46] at cycle numbers around 10 was reported.…”

“…showed fatigue strengths around 130% of yield stress [44], 99% of yield stress [45], and 127% of yield stress [46] at 10 cycles. In the same studies, fatigue strengths around 124% of yield stress [45] and 150% of yield stress [46] at cycle numbers around 10 was reported. This is another observation that signifies the importance of material type in determining the fatigue response of meta-biomaterials.…”

Brittle Fracture Behaviors of Large Die Holders Used in Hot Die Forging

“…The failures of dies and die holders are usually caused by wear, deformation, corrosion and fatigue during the production process [3,4]. Especially, the dies and die holders have to suffer long-term cyclic mechanical and thermal loads [5,6].…”