Engaging the frequently tough requirements of vehicle safety, weight reduction for combustible economy, and manufacturability has influenced the steel industry to create a unique variety of 'super steels' for the automobiles of the future.
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Explanation</u>
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• That steel, though, is far more advanced than the materials of just a few years ago.
• At the forefront of these is Advanced High Strength Steel, AHSS, developed by World Auto Steel’s member companies, which is demonstrating to be something of a vision in automobile production.
• The standard engineering trade-off in steel preference involves considering the need for ultimate strength against flexibility and work-ability – stronger steels tend to be stiffer and less ductile, making them more difficult to develop into cars and more laborious to weld.
• AHSS can retain greatest of the ductility and work-ability of lower grades of steel, while offering much greater strength.
• Where a typical mild steel might have a tensile strength of 300MPa, AHSS can exceed 1500MPa while retaining a highest elongation of 25%, compared to about 40% for mild steel. The intrigue is in the micro-structure, containing a martensite, bainite, austenite phase rather than ferrite, pearlite, or cementite.
