Specific modulus

A commonly used maximum closedloop log modulus specification is 4 2 dB. The controller parameters are adjusted to give a maximum peak in the closedloop servo log modulus curve of -1-2 dB. This corresponds to a magnitude ratio of 1.3 and is approximately equivalent to an underdamped system with a damping coefficient of 0.4,... 

Sample 1 Property - Specific Toughness Strain at Break Specific Young s Modulus Specific Tensile Strength... 

Figure 9.7 Specific properties (strength and modulus + specific gravity) of RPs, wood, aluminum, and steel...

Natural rubber. On heating from -50°C to -2S°C the modulus falls abruptly (glass-to-rubber relaxation) and levels off at the rubber elastic modulus specific to this rather high degree of cross-linking (G 1.2 MPa). In the rubbeiy state the modulus increases with temperature (eqn 3.30). 

Durometer Tensile Elonga- Modulus Specific hardness strength, tion, A STM... 

Keywords polyurethane isocyanurates, diisocyanate, isocyanurate ring, elasticity modulus, specific impact strength... 

Next to DSM several companies are active in research and gelspinning of other polymers than polyethylene. The most promising seem to be PAN (polyaciylonitril) and PVA (polyvinylalcohol). In the figure the state of the art as derived from patents is plotted in the specific modulus/specific strength diagram. 

Optimization criteria describe basic properties of materials. They are also called objective functions. In material optimization the objective functions describe selected properties that were considered as important and decisive for the material s quality and applicability. The solution consists of the determination of those values of design variables that extremize these properties. All physical, chemical and other properties may be treated as material properties. Particularly important for engineering materials are mechanical properties such as strength, Young s modulus, specific fracture energy, durability and specific cost. 

Peel strengths tend to increase with increasing formulation modulus specific adhesion to polar or metal substrates tends to be increased by polar, unsaturated, or aromatic resins and to be decreased by hydrocarbon plasticizers. 

Fibre Specific gravity Ultimate tensile strength Youngs modulus Specific Youngs modulus... 

A generation of new aluminum-lithium alloys have been developed recently for use by the aircraft and aerospace industries. These materials have relatively low densities (between about 2.5 and 2.6 g/cm ), high specific moduli (elastic modulus-specific gravity ratios), and excellent fatigue and low-temperature toughness properties. Furthermore, some of them may be precipitation hardened. However, these materials are more costly to manufacture than the conventional aluminum alloys because special processing techniques are required as a result of lithium s chemical reactivity. 

There are actually a variety of polymer properties that change at the glass transition (modulus, specific volume, enthalpy, entropy, specific heat, refractive index, and dielectric constants), a variety of physical methods to measure the glass transition and, indeed, a variety of ways to define glass transition (5,21). 

Material Modulus, E Tensile strength Density, d Specific modulus Specific strength... 

Considering synthetic fibers in terms of specific tensile strength and modulus specific properties are obtained by dividing the tensile property by the product (density times the gravitation constant g = 9.807 m/s ). 

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