Corrosion Properties of Ultra-Fine-Grained Cu-3 wt%Ti Alloy Fabricated by Combination of Hot Rolling and Aging Treatment.

Although deformation and aging treatments of Cu-3 wt%Ti alloys dramatically enhance their mechanical properties, the corrosion behavior of ultra-fine grained (UFG) Cu-3 wt%Ti alloys produced by a combination of hot rolling and artificial aging has not been extensively explored yet. To bridge this gap, we herein probe the corrosion behavior of an UFG Cu-3 wt%Ti alloy produced by cold rolling and artificial aging, revealing that cast sample corrosion preferentially occurs around the -Cu₄Ti phase. Compared to that of the coarse-grained Cu-3 wt%Ti alloy, the corrosion resistance of its UFG counterpart is remarkably higher, which is ascribed to the effects of grain refinement and enveloping between the -Cu matrix and -Cu₄Ti in the absence of pitting corrosion.

Microstructural Evolution and Electrochemical Properties of HRDSR AZ61- ( = Ca, Ti) Alloys.

The microstructure and corrosion properties of as-cast AZ61 (Mg-6%Al-1%Zn) and AZ61 alloys doped with titanium and calcium and subjected to high ratio differential speed rolling were investigated. Addition of the alloying elements to the AZ61 alloy resulted in remarkable modification of the morphology and the amount of continuous β (Mg17Al12)-phase. Addition of Ti to the as-cast AZ61 alloy causes a decrease in the volume fraction (or discontinuity of the β-phase), leading to strong anodic dissolution.

Microstructure and properties of silicon-incorporated DLC film fabricated using HMDS gas and RF-PECVD process.

The microstructure and characteristics of silicon-incorporated diamond-like carbon film, fabricated using a radio-frequency plasma-enhanced chemical vapor deposition process with hexamethyldisilane [(CH3)3,Si x Si(CH3)3:HMDS] gas as a silicon source, were investigated. Diamond-like carbon films with silicon compositions from 0 to 5 atomic percent were deposited onto ultra-fine grained AZ31 magnesium alloy substrate as buffer layers or multilayers. Si doping led not only to an increase in the bonding ratio (sp3/sp2), but improvements in hardness, critical adhesion, and corrosion resistance.

Microstructural analysis of dehydrogenation products of the Ca(BH₄)₂-MgH₂ composite.

The microstructural analysis of the dehydrogenation products of the Ca(BH₄)₂-MgH₂ composite was performed using transmission electron microscopy. It was found that nanocrystalline CaB₆ crystallites formed as a dehydrogenation product throughout the areas where the signals of Ca and Mg were simultaneously detected, in addition to relatively coarse Mg crystallites. The uniform distribution of the nanocrystalline CaB₆ crystallites appears to play a key role in the rehydrogenation of the dehydrogenation products, which implies that microstructure is a crucial factor determining the reversibility of reactive hydride composites.