Comparison of Mechanical Properties of Milled and Casted Cobalt-Chromium Alloys Using Three-point Bending Test

Abstract

Copyright © 2019. The Korean Academy of Oral & Maxillofacial Implantology This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons. org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. OPEN ACCESS Purpose: The objective of this study was to investigate the mechanical properties of CobaltChromium (Co-Cr) alloys made by conventional casting method and Computer-Aided Design/ Computer –Aided Manufacturing (CAD-CAM) milling method. Material and Methods: Co-Cr alloy specimens (n=8) were made by casting and milling methods. The size of the specimens was 34 mm × 13 mm × 1.5 mm, according to ISO 22674: 2016. Three-point bending test was conducted by universal testing machine, stress and strain values were obtained. Statistical significance was tested using the t-test. Results: Flexural strength of the milled sample was significantly lower than of casted (p < 0.05). Similarly, 0.2% yield strength of milled sample was also lower than of casted (p < 0.05). Conclusion: Although there is a significant difference in mechanical properties of milled and casted Co-Cr alloy, they are both are clinically acceptable.