Duplex stainless steels (DSS) constitute both ferrite and austenite as a matrix. Such a microstructure confers a high corrosion resistance with favorable mechanical properties. However, intermetallic phases such as sigma (σ) and chi (χ) can also form during casting or high-temperature processing and can degrade the properties of the DSS. This research was initiated to develop time-temperature-t...

Metal-on-metal (M-M) joint replacement has raised concerns about the long-term effects of metal wear debris and corrosion products. This review summarizes the current concepts in biological reactivity to metal wear particles, ions, and corrosion products. Attention is focused on Co-Cr-Mo alloy since it is the most diffused and discussed material in arthroplasty.

The ferrochrome alloy is produced by electric arc melting of the mineral chromite (FeCr2O4). It is largely used for the production of stainless steels. Increasing the amount of chromium content in the steel allows for increased corrosion and oxidation resistance. Other alloying elements, such as nickel (Ni) or molybdenum (Mo), aid in making the steel more passive and increasing its stainless pr...

The effects of field-evaporation rate on the quantitative chemical analysis of materials by atom-probe field-ion microscopy are considered. Examples of erroneously high measured values of the Ti concentration in Mo-1.0 at.% Ti and Mo-1.0 at.% Ti-0.08 at.% Zr (TZM) alloys are presented and the cause is shown to have been due to a high field-evaporation rate. The basic arguments used to explain t...

An improvement in the mechanical properties of a biomedical Ni-free Co-Cr-Mo alloy under as-cast condition has been examined by means of tensile tests and microstructure observations. The solubility of N in Co-Cr-Mo alloys increases with increasing Cr content from 29 to 34mass%. This results in a significant improvement in mechanical properties such as yield stress, tensile strength, and fractu...

Metal-on-metal (MoM) bearings have become popular due to a major advantage over metal-on-polymer bearings for total hip arthroplasty in that the larger femoral head and hydrodynamic lubrication of the former reduce the rate of wear. However, concerns remain regarding adverse reactions to metal debris including metallosis caused by metal wear generated at the taper-head interface and another mod...

Pd, Au, and Pd-Au mixtures were deposited via physical vapor deposition onto a Mo(110) substrate, and the surface concentration and morphology of the Pd-Au mixtures were determined by low-energy ion scattering spectroscopy (LEISS), infrared absorption spectroscopy (IRAS), temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS). Pd-Au mixtures form a stable alloy betw...

Post-manufacturing thermal treatments are commonly employed in the production of hip replacements to reduce shrinkage voids which can occur in cast components. Several studies have investigated the consequences of these treatments upon the alloy microstructure and tribological properties but none have determined if there are any biological ramifications. In this study the adsorption of proteins...

Ternary coatings Fe-Co-W with an iron content of 40-55 at.%, cobalt 39-44 at.%, and tungsten 4-12 at.% and Fe-Co-Mo with an iron content of 40-55 at.%, cobalt 39-44 at.%, and tungsten 4-12 at.% were obtained by galvanostatic and pulse electrolysis on the mild steel substrate from iron(III) citrate-based electrolyte. The influence of electrolysis mode and parameters on composition of deposited a...

Cr-Co-Mo (ASTM F75) alloy has been used in the medical environment, but its use as a rigid barrier membrane for supporting bone augmentation therapies has not been extensively investigated. In the present study, Cr-Co-Mo membranes of different heights were placed in New Zealand white, male rabbit tibiae to assess the quality and volume of new bone formation, without the use of additional factor...