Strength axial

The axial strength of the composite can be calculated by applying Eq. (5.107). In the most common case, the matrix is more ductile than the fibers, such that the matrix critical strain exceeds the fiber critical strain, > / 1 low volume fraction of fibers, the fibers located with their ends within a distance 5 of the failure plane do not fracture, but rather simply pull out of the matrix. This movement is resisted by the friction stress, r7. The proportion of fibers for which this occurs is IJl, and the mean stress resisting pull-ont is cryi. The fibers therefore contribute a mean stress of CT/ = el ll and from Eq. (5.107) the strength becomes... 

Figure 11 Axial strength as a function of stress rate at 200 C (EX-20, 400/6.5 substrate). (From Ref. 38, courtesy of SAE.)...

The axial stress approaches a value of 540 psi, far in excess of the high-temperature axial strength of 260 psi sec Table 8. Similarly, the tangential stress approaches 200 psi,... 

Assimilation generally varies considerably from section to section and even between adjacent cells. The alterations of mechanical properties that occur with brown rot, loss of elasticity and axial strength, suggest that the best consolidation treatment should incorporate axial and elastic augmentation. 

Another alternative would be to select a special fabric whose weave is 2 to 1, wrap to fill, and circumferentially wrap the cylindrical sections to the proper thickness, thus getting the required hoop and axial strengths with no extra, unnecessary strength in the axial (longitudinal) direction, as would inevitably be the case with a homogeneous metal tank. 

By custom designing the pipe laminate, superior axial strength and stiffness can be achieved. This can be used to advantage to increase... 

The unifying feature of all fibers spun from LCPs is the very high axial molecular orientation, which leads to extreme anisotropy of microstructure and mechanical properties. In the transverse direction, the strength is only about 20% of the axial strength and the modulus is typically less than 10% of the axial value. The microstructure of LCP fibers reflects the very... 

The ends of the microfibrils create about Itf m point vacancies in the microfibrillar superlattice (Fig. 11). Under applied tensile load they may fail first, eventually by microcrack formation so that the adjacent microfibrils have to carry a heavier load than the rest of the sample. Hence they are first candidates for rupture detectable by the rascals formed at the rupture of tie molecules in at least one amorphous layer of the microfibril affected. Depending on the ratio of axial strength to lateral adhesion of the microfibrils the microcracks will grow parallel (high ratio) or perpendicular (low ratio) to the fibre axis yielding a large number of broken, chains and radicals in the former and a small one in the latter case. Nylon is an example of the former and linear polyethylene of the latter type. 

The equivalent (uniaxial) stress is the uniaxial tensile stress which would have the same damaging action as an applied multi-axial stress state. The proper definition of the equivalent stress depends on the type of the fracture causing flaws, and how such flaws act as cracks (though this remains a matter of some debate). The definition also depends on the fracture criterion for multi-axial stress states, and this should also take into account the action of compressive stresses. Precise information on real flaw distributions and multi-axial strength data are rarely available, and the large scatter of strength values makes unambiguous interpretation of these data difficult. 

Filler Density (g/cm ) Tensile axial modulus, CPa (average value) Tensile axial strength, MPa (average value)... 

Figure 8. Relationship between VCST test and tri-axial strength test or simple shear test (Sasaki 2010).

The axial strengths of the monoliths were determined using a Chatillon LTCM Universal Tensile Compression and Spring Tester with a test head of 1 mm . 

Composition Ti02 SEP wt% Heat Treatment °C Hg Pore Volume cm g Hg Area m g- N BET Area m g Total Pore Volume Hg+Nj cm g Axial Strength kgcm Length Change % TEC dL/°C E-6 200°-400°C... 

Without going into too mnch mathematical and analytical detail, it suffices to state that the axial strength of tubular bonded joints can be estimated by the traditional analytical approaches, such as that developed by Volkersen in 1938 (Adams et al, 1997). According to Volkersen, the maximum adhesive shear stress in a lap joint can be estimated by ... 

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