Fracture Properties of Mg-Alloys Assessed with Nanoindentation

Abstract:

This paper deals with micromechanical properties of biocompatible magnesium alloys MgCa0.8 prepared by extrusion. At first, the microstructure, elastic and hardness properties are assessed at the scale of one micrometer by means of a nanoindenter. Further, determination of fracture mechanism, fracture area and fracture toughness of the alloy is studied with sharp indentation, optical microscopy and SEM and by means of energetic methods. Based on the examination of optical images it was concluded that the Mg matrix is not vulnerable to distinct cracking around indents even for high indentation loads. By computations, it was found the fracture area is very small, about 0.7-3% of the tip contact area based on the assumption of limit values of the target fracture toughness 10-20 MPa·m^1/2.

• Periodical: Materials Science Forum (Volume 891)
• Pages: 257-262
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.891.257
• Online since: March 2017
• Authors: Jiří Němeček*, Vladimír Hrbek, Veronika Petráňová, Petr Hlaváček
• Keywords: Fracture Toughness, Magnesium Alloy, Microstructure, Nanoindentation

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