High strength aluminum alloys, especially those containing zirconium, are historically difficult to grain refine. Early efforts by Alcoa indicated that the addition of lithium to these alloys increases difficulty with grain refinement. Although grain refining of alloys 2090 and 2091 was possible, consistent results were not obtained. Statistically-designed experiments were used to quickly ident...

Understanding the coercivity mechanism has a substantial impact on developing novel permanent materials. However, the current coercivity mechanisms used widely in permanent alloys cannot explain well the amorphous phase produced hard magnetic behavior of Nd-based bulk amorphous alloys (BAAs). Here, we propose that the coercivity in as-cast Nd60Fe30Al10 alloy is from the combination of magnetic ...

Aiming at developing a dental titanium alloy with better mechanical properties and machinability than unalloyed titanium, a series of Ti-Nb alloys with Nb concentrations up to 30% was made. They were cast into magnesia-based molds using a dental casting machine and the mechanical properties and grindability of the castings were examined. The hardness of the alloys with Nb concentrations of 5% a...

The influence of a minor strontium (Sr) modifier on the microstructures and mechanical properties of 7075 Al alloys was investigated in this paper. The grain size of cast 7075 Al alloys was refined from 157 μm to 115 μm, 108 μm, and 105 μm after adding 0.05 wt. %, 0.1 wt. %, and 0.2 wt. % Sr, respectively. The extruded 7075 Al alloys was refined with different degrees of Sr modifier. The mechan...

The microstructural and mechanical properties of the hard phases in CoCrMo prosthetic alloys in both cast and wrought conditions were examined using transmission electron microscopy and nanoindentation. Besides the known carbides of M(23)C(6)-type (M=Cr, Mo, Co) and M(6)C-type which are formed by either eutectic solidification or precipitation, a new mixed-phase hard constituent has been found ...

Formation of bulk metallic glass in quaternary Ti-Zr-Cu-Ni alloys by relatively slow cooling from the melt is reported. Thick strips of metallic glass were obtained by the method of metal mold casting. The glass forming ability of the quaternary alloys exceeds that of binary or ternary alloys containing the same elements due to the complexity of the system. The best glass forming alloys such as...

The casting of cobalt-base alloys in dentistry is comparatively new in relation to the casting of gold alloys and other restorative procedures. It has been less than thirty years since these alloys were introduced to dentistry, but each year they have become more popular. A survey of the choice of dental alloys for removable partial dentures conducted by Lane' in 1949 showed that five times as ...

objectives: micromechanical retention of resin cements to alloys is an important factor affecting the longevity of metal base restorations. this study aimed to compare the bond strength and etching pattern of a newly introduced experimental etchant gel namely nano met etch with those of conventional surface treatment techniques for nickel-chrome (ni-cr) and high noble alloys.  materials and met...