Direct observation of grain rotations during coarsening of a semisolid Al-Cu alloy.
Sintering is a key technology for processing ceramic and metallic powders into solid objects of complex geometry, particularly in the burgeoning field of energy storage materials. The modeling of sintering processes, however, has not kept pace with applications. Conventional models, which assume ideal arrangements of constituent powders while ignoring their underlying crystallinity, achieve at best a qualitative description of the rearrangement, densification, and coarsening of powder compacts during thermal processing. Treating a semisolid Al-Cu alloy as a model system for late-stage sintering-during which densification plays a subordinate role to coarsening-we have used 3D X-ray diffraction microscopy to track the changes in sample microstructure induced by annealing. The results establish the occurrence of significant particle rotations, driven in part by the dependence of boundary energy on crystallographic misorientation. Evidently, a comprehensive model for sintering must incorporate crystallographic parameters into the thermodynamic driving forces governing microstructural evolution.
Institute of Micro and Nanomaterials, Ulm University, 89081 Ulm, Germany.
Jules M
JM
Dake
Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
Jette
J
Oddershede
Nano-Science Center, Department of Chemistry, University of Copenhagen, 2100 Copenhagen, Denmark.
Henning O
HO
Sørensen
Institute of Micro and Nanomaterials, Ulm University, 89081 Ulm, Germany.
Thomas
T
Werz
Institute of Micro and Nanomaterials, Ulm University, 89081 Ulm, Germany.
J Cole
JC
Shatto
Research and Utilization Division, Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan.
Kentaro
K
Uesugi
Department of Physics, Technical University of Denmark, 2800 Kongens Lyngby, Denmark; carl.krill@uni-ulm.de ssch@fysik.dtu.dk.
Søren
S
Schmidt
Institute of Micro and Nanomaterials, Ulm University, 89081 Ulm, Germany; carl.krill@uni-ulm.de ssch@fysik.dtu.dk.
Carl E
CE
Krill
3D microstructural evolution; Ostwald ripening; grain rotation; sintering; x-ray imaging
Nat Commun. 2011;2:298
21540840
Nat Commun. 2015 Jan 14;6:6098
25586429
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Jun;73(6 Pt 1):061502
16906831
Nat Mater. 2002 Oct;1(2):123-8
12618828
Science. 2002 Oct 25;298(5594):811-4
12399586
Science. 2001 Mar 23;291(5512):2392-4
11264531
Science. 2004 Jul 9;305(5681):229-32
15247474
Nature. 2001 Nov 15;414(6861):345-52
11713541