Comparison of in-situ tension and in-situ compression behavior of Mg-AZ80

H.-G. BROKMEIER; N. AL-HAMDANY; R.E. BOLMARO; A. ROATTA; E. A. BENATTI; M. AVALOS; V. VENTZKE; N. SCHELL

Saint George

Conferencia; 18th International Conference on Textures of Materials; 2017

Brigham Young University, Utah.

Tension-compression behavior of Mg and Mg-alloys is longtime known but still of basic interest. The present investigation was performed with a rectangular extruded bar with an initial texture composed of fibre //ND, fibre // ED, {0001} ideal component and {11-20}. Compression tests were made with compression axis //ND, //TD and // ED of the extruded bar, while tension was done with samples of ED, TD and 45° oriented samples. In- situ experiments were carried out with high energy X-rays for fast measurements to follow texture evolution as well as lattice strain and microstrain evolution. The beamline HEMS@Petra III was used with about 87keV. In all cases one can see the strong influence of the initial texture on the texture evolution and, particularly for tension, the different behavior of initial texture components on reactivity during plastic deformation is more evident. The compression texture of Mg shows an orientation of the // to the compression axis with different scatter and different texture sharpness. MgAZ80 shows only a moderate texture sharpness compared to other alloys or commercially pure Mg. Tensile load leads to a double pole in the basal pole figure with tilt of 15° in ±TD. Texture sharpness decreases in all cases of tension.During in situ loading the typical stress strain curve was documented and, in parallel, up to 250 diffraction patterns were collected. Due to the high synchrotron energy, the wavelength is very short and consequently complete Debye-Scherrer rings were obtained. Lattice strain behavior will be correlated on one hand related to the texture evolution and on the other hand as diffraction pattern parallel and perpendicular to the loading direction. The synchrotron experiments were accompanied by texture simulations, bulk texture analysis using neutron diffraction and EBSD investigations. Besides intensity pole figures (crystallographic texture) we also present line broadening pole figures (microstrain).[1] S.-B. Yi, C.H.J. Davis, H.-G. Brokmeier, R.E. Bolmaro, K.U. Kainer & J.Homeyer (2006) Acta Mat. 54, 549-562.[2] H.-G. Brokmeier, M. Jiang, E. Maawad, B. Schwebke & T. Lippmann (2011) Mat. Sci. Forum 690,198.[3] Z. Zhong, H.-G. Brokmeier, E. Maawad & N. Schell, (2015) Mat. Sci. Engineering A639, 519.