Microstructural Characterisation of Co-Cr-Mo Casting Dental Alloys

Abstract

The study compares the microstructure of three commercial dental cobalt matrix alloys with related chemical composition declared by the manufacturer. Casts were produced with lost wax method, then melted and casted with centrifugal induction casting machine. The Co-Cr-Mo alloys were casted according to the manufacturers procedure. The samples' chemical composition and phase composition, respectively, using WD-XRF (Wavelength Dispersive X-Ray Fluorescence) and XRD (X-ray Diffarction) methods were analysed. Casts microstructure by mean of LOM (Light Optical Microscopy), SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) were investigated. Vickers hardness HV10 was measured. Quantitative microstructure evaluation was performed by means of computer image processing. The results of the chemical composition indicate the high stability of the chemical composition for alloy A. In case of alloys B and C, there was a significant difference in carbon content. Quantitative differences in image of microstructure between of castings A and B, C were noticed. The greater amount of precipitates was recorded for castings with higher carbon content. In all investigated castings, the presence of β matrix solution and M23C6 carbide precipitations was found.

Artigo Retratado

“…The passive zone of the Ni-Cr alloys extends approximately from -0.040 V sce with average current densities ordered from lowest to highest of 0.42 μA / cm 2 , 0.53 μA / cm 2 and 0.75 μA / cm 2 for VeraBond V, VeraBond and VeraBond II, up to their potentials of rupture that are 0.22 V sce , 0.14 V sce and 0.420 V sce respectively. The current density of all Co-Cr and Ni-Cr alloys under study increases rapidly from their rupture potential, due to the dissolution of the interdendritic zone rich in Ni and poor in Cr and Mo [26,27].…”

Effect of Annealing Time and Temperature Parameters on the Microstructure, Hardness and Strain-Hardening Coefficients of 42CrMo4 Steel

“…The structure was investigated on the polished and etched transverse section of the samples by light optical microscopy (LOM) and scanning electron microscopy (SEM). Moreover, the phase structure was evaluated qualitatively and quantitatively by X-ray dispersive diffraction (XRD) using the XTRa ARL X-ray diffractometer (manufactured by Thermo Fisher Scientific, Massachusetts, USA) and the parameters described in [38,39]. Vickers hardness was measured before and after the heat treatment and compared with the hardness results of the upset samples.…”

The influence of the nucleus pulposus on the stress distribution in the natural and prosthetic intervertebral disc

“…In order to achieve credible results, materials were assigned to each element. Although metal biomaterials present high mechanical properties, unassisted metal alloys are used mostly in dental surgery [33], while in orthopaedics, particularly in prosthetic intervertebral disc, they cooperate with various plastic materials, such as UHMWPE used in our research. Properties of materials are presented in Table 1.…”