Measurements of the elastic constants,the specific heat and the entropy of grain boundaries have been performed by utilizing ultra-fine grained materials (Pd, 6nm grain size; Mg, 12 nm grain size; CaF2, 7 nm grain size) about 30 to 50 vol% of which consist of grain boundaries. The results obtained suggest that (1) The interatomic potentials in grain boundaries in metals differ from the lattice ...

A Fe-20.1Mn-1.23Si-1.72Al-0.5C TWIP steel with ultra-fine grain structure was successfully processed through Equal Channel Angular Pressing (ECAP) at warm temperature up to four passes following the BC route. The microstructure evolution was characterized by Electron Back Scattered Diffraction (EBSD) to obtain the grain maps, which revealed an obvious reduction of grain size, as well as a decre...

Equal channel angular rolling (ECAR) process is one of the severe plastic deformation (SPD) methods that have been used to make ultra-fine grain (UFG) materials with improving the mechanical properties of samples. After performing the process at several paths, a large strain is applied to the material that can cause decreasing the grain size and improving the mechanical and physical properties ...

Cluster computing is still the most cost-effective solution to meet the increasing demand for computing power. Clusters are typically based on commodity computing hardware with specialized interconnection networks (IN). These cluster interconnects differ from commodity networks by higher bandwidth, lower latency, lower CPU utilization and improved scalability. But even with these sophisticated ...

in this study, ultrafine grained 2024 al alloy based b4c particles reinforced composite was produced by mechanical milling and hot extrusion. mechanical milling was used to synthesize the nanostructured al2024 in attrition mill under argon atmosphere up to 50h. a similar process was used to produce al2024-5%wt. b4c composite powder. to produce trimodal composites, milled powders were combined w...

Oxidative scrubbing is used to remove H2S from gas streams. A key problem in regeneration of the absorbent is the removal of fine particles of sulphur from the suspension of the scrubbing liquid. Dispersions of ultra-fine bubbles have been called "colloidal gas aphrons" or aphrons for short. These dispersions have interesting properties and it was found that they have particular advantages in t...

Systematic experiments have been performed to investigate the rate sensitivity of deformation in fully dense nanocrystalline Ni using two different experimental techniques: depth-sensing indentation and tensile testing. Results from both types of tests reveal that the strain-rate sensitivity is a strong function of grain size. Specifically microcrystalline and ultra-fine crystalline pure Ni, wi...

While ultra-deep-submicron design presents increasingly difficult challenges for standard synchronous design practices, recent research in asynchronous design techniques is making asynchronous circuits an increasingly practical alternative. These challenges include the increasing pressure for low-power, the growing challenge of predicting increasing impact of wire load and delay, and the perfor...

A nano/ultra-fine grain Al-0.2wt% Zr alloy was produced by accumulated roll bonding (ARB) processafter 10 cycles. The fraction of high angle grain boundaries increased from 8% to 65.4% during 10passes during ARB process. This alloy was subjected to tensile test at different temperatures (523,573and 623 K) and strain rates (0.1 and 0.01 s-1). The optimum condition of temperature and strain rate ...

In this research, the Planetary mill was used for mechanical alloying (MA) of Ti and Alpowder mixture with equal at% (Ti50Al50). The effect of various factors, such as process control agent(PCA), speed of rotation of vial and ball-to-powder weight ratio, on process were studied and the bestcondition to synthesis the alloy was determined. Study on X-ray diffraction (XRD) patterns showedthat at p...