Flexural strength effect

As with the effect of water absorption on flexural strength, effects of a few repeated freeze-thaw on composite deck boards are also not very significant. For example, three-cycle freeze-thaw (hygrothermal) test on GeoGeck composite deck boards, conducted by PFS Corporation (Madison, WI), showed an increase in flexural strength from 1909 + 59 to 2033 + 35 psi, or by 6.5%. 

Flexural modulus, effect on, 134 Flexural strength, effect on, 134 Impact resistance, effect on, 134... 

Bifunctional oligomers, 163 Bifunctional polymers, 163 Chloroparafins, 163 Compatibility, effect on, 161 Covalent bonds with wood fiber, 161 Dispersing effect, 174 Fiber dispersion, effect on, 161 Flexural modulus, effect on, 168, 174 Flexural strength, effect on, 168, 174 Flowability, effect on, 161... 

Flexural modulus, effect on, 129 Flexural strength, effect on, 129 Tensilt modulus, effect on, 130 Tensile strength, effect on, 130 Fine particles, 126 Fire codes, 461 Fire endurance, 461 Fire, 48, 80, 461-491 performance, 485-491 rating, 461, 464 resistance, 48, 80 Firebrake ZB, 470 Firemaster CP-44HF, 471 Firemaster PBS-64HW, 471 Fish-skin, 617... 

Flexural modulus, effect on, 147 Flexural strength, effect on, 147 In limestones, 146 In dolomite, 146 Mohs hardness, 146 Moisture content, 146 Muscovite, 146 Oil absorption, 146 Particle size, 146 Reinforcing effects, 146 Speciflc gravity, 146 Thermal properties, effect on, 146 Water absorption... 

Flexural modulus, effect on, 154, 155 Flexural strength, effect on, 154, 155 Water absorption, effect on, 154, 155 Naphthalates, 203 Narrow MWD polymers, 650 National Institute of Standards and Technology, 376 Natural fiber, 11, 125 Natural graphites, 80 Natural weathering, 592 Near infrared spectroscopy, 186 Neat plastics, 21, 258, 259, 268, 276, 278, 280... 

Energy of break, effect on, 137 Flexural modulus, effect on, 137 Flexural strength, effect on, 137 Impact restance, effect on, 137, 138 Mohs hardness, 137 Moisture content Mold shrinkage, effect on, 137 Particle size, 137, 139 Plastic softening point, effect on, 137 Specific gravity, 137 Specific surface area, 137 Warpage, effect on, 139 Water absorption, effect on, 137, 139 Tannins, 75, 84, 94, 105, 106 Stains on a deck, 105, 106 TBBPA (tetrabromobisphenol-A), 471... 

Such degradation of the surface causes little effect on either flexural strength or flexural modulus of elasticity but the influence on the impact properties is more profound. In such instances the minute cracks form centres for crack initiation and samples struck on the face of samples opposite to the exposed surface show brittle behaviour. For example, a moulded disc which will withstand an impact of 12 ftlbf without fracture before weathering will still withstand this impact if struck on the exposed side but may resist impacts of only 0.75 ftlbf when struck on the unexposed face. 

The effect on cement C is particularly dramatic and the flexural strength of cement C is exceptionally high. In part, this is to be attributed to the high powder/liquid ratio. These results are to be compared with the flexural strengths of early polyalkenoate cements which were c. 10 MPa. 

Consideration of the relationship between the effects of radiation on homopolymers and copolymers raises the question of the variation from homopolymer behaviour with sequence length. Every copolymer has a distribution of sequence lengths for each comonomer. At what minimum sequence length does methyl methacrylate not show the high scission of PMMA The future will probably see the development of processes for making polymers with controlled mini-block sequences to maximize a number of properties such as scission yield, adhesion, flexural strength, Tg.. 

Figure 11. Effect of temperature of lOwt.% NaOH solution on retention of flexural strength of iso-UP.

Shih, G.C. and Ebert, L.J. (1986). Interface strength effects on the compressive-flexure/shear failure mode transition of composites subjected to four-point bending. J. Mater. Sci. 21, 3957-3%5. 

Effect of through-the-thickness stitches on flexural strength and Mode I interlaminar fracture toughness of carbon fiber-epoxy matrix composites manufactured using unidirectional prepregs". 

Tensile and flexural strengths values are usually lower than what would be expected from compressive strength values. This probably reflects the effect of laminations and other defects in the shotcrete on tensile strength. Flexural strength values follow a similar relationship observed for regular concrete. 

Figure 5.49 Effect of porosity on the flexural strength of AI2O3 at room temperature. Reprinted, by permission, from W. Callister, Materials Science and Engineering An Introduction, 5th ed., p. 413. Copyright 2000 by John Wiley Sons, Inc.

Thus the effects of the rate of application of stress and the ambient temperature must be recognized when polymers are used as structural materials, and definite rates and temperatures must be specified for tests, such as those for tensile and flexural strengths cited in Chapter 3. A knowledge of the structure of polymers is essential for the understanding of these effects, which differ from the effects of stress and temperature on all other materials of construction. 

Figure 9. Effect of coupling agents on flexural strengths of glass cloth-reinforced Ihermoseiting resins, dry and wet after 24 h boil.

Effect of coupling agents on the flexural strength of a structural epoxy-fiberglass laminate... 

The work of Sterman and Marsden and Plueddeman was carried out with glasscloth polymer laminates (10, II, 14,15). In this way the effect of the silane could be optimized as to time and temperature of the molding cycle. Additionally, the glass was being used in its maximum strength form in that it was continuous. An additional factor is the absence of any shear forces. As an example, for a polystyrene laminate, the use of an epoxyfunctional silane increased the flexural strength 90% over the bare... 

Effect of porosity on flexural strength of composites with code 1723 matrix (reproduced by permission of Am. Ceram. Soc. Bull.) . 

Only a slight drop in the flexural strength of a woven Nicalon /Al203 composite was observed by Fareed et al. (1990) after quenching through A T = 1000°C and 1200°C. This was attributed to the effectively engineered weak fibre/matrix interface. 

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