Strength transfer

Distinction must be made between systems in which bonds are localized at the points of particle contact and those in which the void space between particles is partially or completely filled with strength-transferring substance. Localized bonding is considered first, while some binder-filled systems are treated in Section 2.4. 

SiC whiskers. The particulates or whiskers were uniformly distributed among the carbon fibers and preforms prepared from the treated fibers were directly infiltrated by molten A1 under applied stress. It was found that the longitudinal tensile strengths of hybrid composites were greatly improved, although their fiber volume fractions were quite low compared to those of conventional composites. With this hybridization method, it is also practical to tailor the fiber volume fraction of composites from 60 to 25 vol%, which is not possible in direct infiltration of fiber preforms by pressure easting. The results obtained lead to the conclusion that particulate or whisker additions do not act directly as reinforcements, but as promoters to improve the infiltration performances of fiber preforms and consequently, increase the strength transfer efficiency of carbon fibers. The addition of particulates or whiskers can also improve other properties of the composites, such as hardness and wear resistance. 

Finally, because the reactivity of a bridging oxygen depends on the M-O bond strength, transfer of an electron to the metal can dramatically accelerate the dissociation rate. This reductive pathway is marked 4 in Fig. 4. 

The physical mass-transfer rate of o2one into water is affected by the gaseous o2one concentration, temperature, pressure, gas dispersion, turbulence, mixing, and composition of the solution, ie, pH, ionic strength, and the presence of reactive substances. Mass transfer of gaseous o2one into... 

Nittile mbber is much like SBR in its physical properties. It can be compounded for physical strength and abrasion resistance using traditional fillers such as carbon black, siUca, and reinforcing clays. The primary benefit of the polymer is its oil and solvent resistance. At a medium ACN content of 34% the swell in IRM 903 oil at 70°C is typically 25—30%. Nitrile mbber processes on conventional mbber equipment and can be compression, transfer, or injection molded. It can also be extmded easily. 

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