Material Behavior Characterization via Multi-Directional Deformation of Sheet Metal: Session IV
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Shaping and Forming Committee
Program Organizers: Daniel Coughlin, United States Steel Corp; Kester Clarke, Los Alamos National Laboratory; Piyush Upadhyay, Pacific Northwest National Laboratory; John Carsley, Novelis, Inc.
Tuesday 2:00 PM
February 25, 2020
Room: Theater A-1
Location: San Diego Convention Ctr
Session Chair: Piyush Upadhyay, Pacific Northwest National Laboratory
2:00 PM
Formability of Textured Anisotropic Uranium Plate: Ryan Mier1; Daniel Coughlin1; Rodney McCabe1; Carolus Osborn1; 1Los Alamos National Laboratory
Understanding how processing affects mechanical properties of depleted uranium is crucial for final material performance and plays an important role in nuclear energy applications. We have created differences in texture in warm rolled plate through varying rolling direction and deformation at each pass in our schedule. By altering the strain path of the material through different rolling schedules, the final texture and therefore material formability in each direction is also changed. From data gathered via EBSD and by using the plates to do a small scale forming study after rolling, we aim to help understand and inform the way we create material, and control our processing path in order to achieve desired mechanical properties and deformation characteristics.
2:20 PM
In-situ Neutron Diffraction of Strain Path Change Effects in Cold-rolled MgAZ31B Sheet: Karl Sofinowski1; Steven Van Petegem1; Jan Capek1; Helena Van Swygenhoven1; 1Paul Scherrer Institut
There has been growing interest in wrought magnesium alloys for strong, lightweight structural components in cars, aircraft, and electronics. These components are subjected to non-linear loading conditions during cold-forming and use, which is known to influence their mechanical properties. It is therefore important to study the microstructural evolution during strain path changes in these alloys to understand their macroscopic response under such conditions. In situ neutron diffraction has been used extensively to investigate the evolution of intergranular strain during loading to provide insight on the relative behavior of different magnesium alloy deformation modes during uniaxial tension/compression tests. In this work, we report on results from in situ neutron diffraction experiments combined with in situ acoustic emission of strain path changes of cold-rolled Mg AZ31B sheets. It is found that, while dislocation slip prevails as the main deformation mechanism, twinning activity strongly depends on the nature of the strain path change.
2:40 PM
Strain Localization and Damage in a α+β Titanium Alloy: A Study of Microstructure Heterogeneity and Strain Path Effects: Jiyun Kang1; Ikuho Nakahata2; C. Cem Tasan1; 1Massachusetts Institute of Technology; 2Tokyo Institute of Technology
Ti alloys have been extensively employed in aerospace applications, due to their high specific strength and superior corrosion resistance, but their limited room-temperature formability still remains as a manufacturing bottleneck. The present work focuses on understanding microstructural mechanisms which govern plasticity and damage evolution in an α+β titanium alloy. These micro-mechanisms are systematically investigated by carrying out in-situ uniaxial and biaxial tensile deformation experiments, and supporting scanning electron microscopy and microscopic-digital image correlation analysis. A particular focus is on strain path effects on microstructural plasticity and damage processes.
3:00 PM Cancelled
The Effect of Texture on the Deformation Behavior of Cold Rolled Aluminium Under Shear-compression Loading: Shibayan Roy1; Ashoktaru Chakraborty1; 1Indian Institute of Technology (IIT) Kharagpur
Shear-compression specimens were prepared with at 0˚ and 90˚ angle with RD (|| RD and || TD) from cold-rolled Al sheets and deformed at low (0.001 s-1), intermediate (1 s-1) and high (100 s-1) strain rates. || RD shows higher strength compared to || TD for low and high strain rates, difference being the highest for low strain rate. However, at intermediate strain rate, both specimens show nearly equivalent strengths. Strain localization for || RD starts from centre at low strain rate while that for || TD from corner due to high shear to normal strain ratio on plane perpendicular to compression axis. Strain localization at high strain rate occurs diagonally for both specimens. ND-IPF map of || RD shows elongated grains along shear direction. For || TD specimens at low strain rate, ND is oriented mostly along <223> direction while at intermediate strain rate, ND-IPF shows almost random orientation
3:20 PM Cancelled
Grain Refinement and Texture Modification of thin Mg-3Al-1Zn Sheets by ECAB Method: Ming Cheng1; Shi-hong Zhang1; 1Institute of Metal Research, Chinese Academy of Sciences
Based on a novel processing method-Equal Channel Angular Bending (ECAB)-is proposed to combine the deformation characterizes of Equal Channel Angular Pressing (ECAP) and bending processing, experiments are conducted on thin Mg-3Al-1Zn sheets (thickness 2mm) at room temperature, 423K, 473K and 523K to study the effect of deformation temperatures. Moreover, three different deformation paths similar to router A, router C and router AC in ECAB are also investigated at temperature of 473K. Results obtained from microstructure observation and texture detection elucidate that ECAB can successfully refine the grain size and modify the texture simultaneously. Gradient distribution of grain size and texture type formed for the periodic deformation of ECAB can achieve better balance of mechanical properties between strength and ductility which reveals that different regions present different deformation mechanisms. Further, special attentions are paid on the role of deformation paths.