Anisotropic fracture behavior of AZ31 magnesium alloy sheets as a function of the stress state and temperature. (November 2019)

• Record Type: Journal Article
• Authors: Wang, Qiaoling; Bertolini, Rachele; Bruschi, Stefania; Ghiotti, Andrea
• Is Part Of: International journal of mechanical sciences. Volume 163(2019)
• Publication Date: 2019-11
• Subjects: Magnesium alloy -- Sheet metal forming -- Anisotropy -- Elevated temperature -- Stress state -- Fracture criterion; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2019.105146
• Languages: English
• ISSNs: 0020-7403

Abstract

Highlights: AZ31B sheets fracture behavior is affected by stress state, rolling direction and temperature. A temperature-dependent term is added to the MMC fracture criterion. Satisfactory prediction between experimental and predicted fracture loci at varying temperature and rolling direction. Abstract: The paper aims at describing the fracture behavior of AZ31 magnesium alloy sheets as a function of the temperature, stress state, and rolling direction. To this aim, fracture tests were carried out at room temperature, 100 °C and 300 °C using different specimen geometries cut at different orientations with respect to the sheet rolling direction. The fracture strain values were measured making use of the Digital Image Correlation (DIC) approach and the fracture surfaces qualitatively characterized by means of stereoscopy and Scanning Electron Microscopy (SEM). Afterwards, the AZ31 fracture locus as a function of the stress state, temperature and rolling direction was constructed. To analytically predict the fracture locus, a temperature-dependent parameter was added to the Modified Mohr Coulomb (MMC) fracture criterion; the newly proposed criterion was calibrated on the basis of the experimental data obtained from the tests previously mentioned, proving to be suitable to predict the AZ31 fracture locus for tension-dominated regions at varying temperature.