Strain to fracture

As another example, a synergistic enhancement of tensile strength has been reached in blends of a sulfo-nated polyacrylonitrile terpolymer (SPAN) with a polyurethane (PU) cationomer [23]. Maximum enhancement was achieved at a blend composition of 30/70 (PU/ SPAN). At this blend composition, the tensile strength was raised from an initial value of 78.5 MPa to 196 MPa and the strain-to-fracture was at its highest. The en-... 

The ability to withstand shatter. A measure of how much energy can be absorbed before rupture. Easily shattered materials (small strain to fracture) are termed brittle. 

As with most fibers derived from the vegetable kingdom, the individual fibers vary considerably in strength. Their strain to fracture is about 1.7%. The density of jute is 1.5 g cm. Jute fibers absorb a considerable amount of water, typically showing a regain value of about 15 wt% at 65% relative humidity. 

The strain to fracture, however, is the product of the imposed strain rate and the... 

The strain to- fracture is expectai to be related to the craze flow stress, with craze fibril breakdown occurring more rapidly at higher stresses. Since the flow stresses are related to the volume fraction of PB through the craze growth velocities, the strains to fracture are also expected to relate to the rubber content. 

Sample Yield Strength (MPa.) Tensile Strength (MPa) Plastic Strain to Fracture (/o) Relative Elastic Modulus "... 

Fig. 28. Dependence of strain to fracture in blends with low molecular weight PB with increasing weight fraction of PB...

A big difference behavior, as expected, was evaluated from hot torsion conditions, the ductility of the material was evaluated as a plot of strain to fracture vs. Strain rate (Figure 5). A big difference was evaluated between 200 and 225 °C for all the strain rates investigated. Two different behavior were evidenced from 200 and 225 °C and 250°C. In this temperature condition good ductility values were recorded, in particular for 10"2 s 1 strain rate. At 250 °C, in fact the strain to fracture increase with increasing strain rate up to 10"2 s"1 and then decreases with increasing strain rate. 

Figure 5. Ductility of the material calculated as Strain to fracture vs. Strain rate for all the...

The warm forming behavior of 2014 aluminum alloy stabilized with small Zr additions was studied by employing torsion tests in the temperature and strain rate ranges of 200-300 °C and 10"3-1 s 1 respectively. The alloy ductility was measured as strain to fracture in all the temperature and strain rate investigated by showing a different behavior between 250-300 °C and the lower temperatures. The activation energy of the material was calculated... 

Figure 2. SEM image of a blend with 10% PS strained to fracture and then cryogenically fractured parallel to the direction of deformation. The parameters that describe the void geometry are defined in the schematic.

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