Fusing, bond strength

The commonly accepted structure of fused quartz is one of randomly bonded SiO 4 tetrahedra. Relying on the high bond strength within these tetrahedra, grinding of a coarse fused quartz should have little effect on its surface structure. Therefore, it is possible to predict that AHa and ASa for fused quartz should be independent of particle size. 

If molecular weights are reduced to the point where the phenolic is water soluble, dramatic decreases in green and dry bond strength are obtained at high phenolic concentrations the phenolic now forms the continuous phase and prevents the latex from fusing. Thus to... 

Special low fusing porcelain veneers are appHed to pure (unalloyed) titanium dental castings. It is important that firing be done either in a vacuum or inert atmosphere to protect the metal surface from excessive oxidation. The strength of the metal-ceramic bond is apparently adequate although the bonding is thought to involve primarily a mechanical rather than a chemical component. 

Available forms Structural shapes of all types, plates, rods, wire foil flakes, powder (technical and USP). Aluminum can be electrolytically coated and dyed by the anodizing process (see anodic coating) it can be foamed by incorporating zirconium hydride in molten aluminum, and it is often alloyed with other metals or mechanically combined (fused or bonded) with boron and sapphire fibers or whiskers. Strengths up to 55,000 psi at 500C have been obtained in such composites. A vapor-deposition technique is used to form a tightly adherent coating from 0.2 to 1 mil thick on titanium and steel. 

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