By restricting the dilated deformation, surface modification can stimulate multiple shear banding and improve the plasticity of bulk metallic glasses (BMGs). Aimed at modifying the surface of BMGs by thin layers, a crystalline Ni coating with ultrafine grains was coated on the surface of a Ti-based BMG by electroless plating. With a thickness of about 10 μm, the prepared thin coating could effe...

In the present work, nano/ultrafine structured Al/Brass composite was produced by accumulative roll bonding (ARB) up to eight cycles. The evolution of grain refinement and deformation texture and their effect on the mechanical properties were investigated. It was observed that by increasing the ARB cycles, due to the difference in flow properties of the metal constituents, brass layers necked, ...

The olivine-rich Divnoe achondrite contains numerous large olivine grains which have a lamellar or banded appearance in backscattered electron images, caused by minor compositional differences. One such grain, viewed in transmitted light, displays a system of lamellae with the same orientation and scale as the compositional banding. The only process known to produce such stmcture and chemical v...

ABSRACT A comparative study of the surface microstructural changes after fatigue in an ultrafine grained and coarse grained aluminum alloy was performed using orientation imaging microscopy (OIM). The fraction of low angle boundaries with misorientation less than 2.5 ̊ increased for both the coarse and ultrafine grained alloys. A consistent decrease in the fraction of low angle boundaries, with ...

Abstract To realize high areal density, hard disk drives larger than 4 Tbit in −2 , ultrafine FePt grains of less 5 nm and grain density 24 T are required. Although there have been many investigations to reduce the size FePt, only a few reports on control density. increase we focused three aspects surface morphology density: nucleation sites substrate surface, free energy, lattice mismatch. We ...

The monotonic and cyclic deformation behavior of ultrafine-grained metastable austenitic steel AISI 304L, produced by severe plastic deformation, was investigated. Under monotonic loading, the martensitic phase transformation in the ultrafine-grained state is strongly favored. Under cyclic loading, the martensitic transformation behavior is similar to the coarse-grained condition, but the cycli...

The tandem differential mobility analyzer (TDMA) technique was applied to determine the hygroscopicity and volatility of atmospheric ultrafine particles in three sites of urban Gwangju, industrial Yeosu, and coastal Taean in South Korea. A database for the hygroscopicity and volatility of the known compositions and sizes of the laboratory-generated particles wasfirst constructed for comparison ...