Aluminum alloys are progressively used in the automobile industry due to several advantages such as low specific weight, good formability, good corrosion resistance and a nice surface appearance. The standard production forming processes such as extrusion and forging, can give rise to large variations in the tensile, fatigue and fracture properties. In AlMgSi alloys (6061, 6062, 6060 and 6082), yield stress have been shown to have only a weak dependence on grain size. However, a large part of the variations in other properties can be traced back to differences in grain size.
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Monthly Archives: January 2013
Wrought Aluminum Alloys for General and Special Applications: Part Two
Super plasticity is the property of certain metallic materials that very high elongations without contraction till breakage can be achieved at suitable working conditions. These elongations are from few hundred to 1000% or even more. Such a method of working occurs at low strain rates, high working temperatures, and corresponding microstructure of material. Needed working stresses values are considerably lower than in working ordinary materials. Excellent work abilities enable wide range of applications of super plastic materials for various purposes.
True Stress – True Strain Curve: Part Three
The parameters that are usually determined from the true stress – true strain curve include true stress at maximum load, true fracture stress, true fracture strain, true uniform strain, true local necking strain, strain-hardening exponent and strength coefficient.
Engineering Stress-strain Curve: Part Three
The engineering tension test is widely used to provide basic design information on the strength of materials and as an acceptance test for the specification of materials. In the tension test a specimen is subjected to a continually increasing uniaxial tensile force while simultaneous observations are made of the elongation of the specimen. The parameters, which are used to describe the stress-strain curve of a metal, are the tensile strength, yield strength or yield point, percent elongation, and reduction of area. The first two are strength parameters; the last two indicate ductility.