Strengthening composite

Boron carbide (B C) is a hard, black crystal that is used as an abrasive powder and as an additive to strengthen composite parts in aircraft. 

Maleated coupling agents are also widely used to strengthen composites containing fillers and fiber reinforcements. Interactions... 

The particle-reinforced composites can be further classified into large-particle composites and dispersion-strengthened composites on the basis of particle size [23]. 

Particle reinforced composite systems can be either large particle or dispersion strengthened. If a composite is reinforced by large particles (larger than 0.1 [xm and equiaxed, which are harder and stiffer than the matrix), mechanical properties are dependent on volume fractions of both components and are enhanced by increase of particulate content. Concrete is a common large particle strengthened composite where both matrix and particulate phases are ceramic materials. 

Large particle reinforced composite systems are utilised with all three types of materials (metals, ceramics and polymers). Concrete is a common large particle strengthened composite where both matrix and particulate phases are ceramic materials. 

Karbhari VM, Zhao L Issues related to composite plating and environmental exposure effects on composite-concrete interface in external strengthening. Composite Structures, 1997 40(3-1) 293-304. DOI 10.1016/s0263-8223(98)00031-2. 

De Lorenzis, L. and Teng, J. G. (2007), Near-surface mounted reinforcement an emerging technique for structural strengthening . Composites Part B Engineering, Vol. 38, Issue 2, pp. 119-143. 

As noted in Figure 16.2, large-particle and dispersion-strengthened composites are the... 

For dispersion-strengthened composites, particles are normally much smaller, with diameters between 0.01 and 0.1 xm (10 and 100 nm). Particle-matrix interactions that lead to strengthening occur on the atomic or molecular level. The mechanism of strengthening is similar to that for precipitation hardening discussed in Section 11.9. Whereas the matrix bears the major portion of an applied load, the small dispersed particles hinder or impede the motion of dislocations. Thus, plastic deformation is restricted such that yield and tensile strengths, as well as hardness, improve. 

Large-particle and dispersion-strengthened composites fall within the particle-reinforced classification. 

The most developed application of UDD is their use for strengthening composite electrochemical chromium-based coatings. Ultradisperse diamond is introduced into the standard chromium-plating electrolyte usually as suspension. The... 

Karbhari, V.M., Abanilla, A., 2007. Design factors, reliabihty, and durability prediction of wet lay-up carbon/epoxy used in external strengthening. Composites Part B 38, 10—23. 

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