Metals are an especially important class of materials. They are distinguished by several special properties, namely their high thermal and electrical conductivity, their ductility (i. e., their ability to be heavily deformed without breaking), and the characteristic luster of their surfaces. Their ductility, together with the high strength that can be achieved by alloying, renders metals particularly attractive as engineering materials.
In nature, metals occur only seldom as they possess a high tendency for oxidation. If one looks at the pure elements, more than two thirds of them are in a metallic state. Many elements are soluble in metals in the solid state and thus allow to form a metallic alloy. For instance, steels can be produced by alloying iron with carbon. The large number of metallic elements offers a broad range of possible alloys. Of most technical importance are alloys based on iron (steels and cast irons), aluminum, copper (bronzes and brasses), nickel, titanium, and magnesium.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
الرجوع الى لوحة التحكم
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