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

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

St George, Utah

Conferencia; 18th International Conference on Textures of Materials (ICOTOM-18); 2017

Brigham Young University

Tension-compression behavior of Mg and Mg-alloys is longtimeknown but still of basic interest. The present investigation wasperformed with a rectangular extruded bar with an initial texturecomposed of fibre //ND, fibre // ED, {0001}ideal component and {11-20}. Compression tests were madewith compression axis //ND, //TD and // ED of the extruded bar,while tension was done with samples of ED, TD and 45° orientedsamples. In- situ experiments were carried out with high energy X-rays for fast measurements to follow texture evolution as well aslattice strain and microstrain evolution. The beamline HEMS@PetraIII was used with about 87keV. In all cases one can see the stronginfluence of the initial texture on the texture evolution and,particularly for tension, the different behavior of initial texturecomponents on reactivity during plastic deformation is moreevident. The compression texture of Mg shows an orientation of the // to the compression axis with different scatter anddifferent texture sharpness. MgAZ80 shows only a moderate texturesharpness compared to other alloys or commercially pure Mg.Tensile load leads to a double pole in the basal pole figure with tilt of15° in ±TD. Texture sharpness decreases in all cases of tension.During in situ loading the typical stress strain curve was documentedand, in parallel, up to 250 diffraction patterns were collected. Due tothe high synchrotron energy, the wavelength is very short andconsequently complete Debye-Scherrer rings were obtained. Latticestrain behavior will be correlated on one hand related to the textureevolution and on the other hand as diffraction pattern parallel andperpendicular to the loading direction.The synchrotron experiments were accompanied by texturesimulations, bulk texture analysis using neutron diffraction and EBSDinvestigations. Besides intensity pole figures (crystallographictexture) we also present line broadening pole figures (microstrain).