Alumina is the most cost - effective and widely used structural engineering material in the family of advanced ceramics. The raw materials from which this high - performance, technical grade ceramic is produced are readily available and reasonably priced, resulting in good value for the cost in fabricated alumina shapes.
Hence, alumina (corundum, ?-Al2O3) is considered the “ workhorse material ” of the structural ceramics industry. Its high hardness, abrasion resistance, and chemical inertness makes it an ideal material to perform well in a variety of aggressive environments, ranging from mining industry to chemical industry to metal manufacturing and processing, to ceramic armor and biomedical applications. Its electrically insulating nature, coupled with its moderate thermal conductivity, reasonably low dielectric permittivity, and low dielectric loss, offer a plethora of applications that include electronic substrates for integrated circuits (ICs) and automotive spark plugs.
However, these advantageous properties are partially offset by the material ’s low tensile and flexural strengths and fracture toughness, and low thermal shock resistance (see Figure 6.1 ). Hence, the decision to include alumina - based wearing parts in engineering designs must be assessed judiciously so as to avoid catastrophic failure in service under harsh conditions. An overview of the important properties of alumina ceramics is provided in Table 7.1. The wide range of values attests to the fact that alumina ceramics depend on processing parameters, including the sintering temperature, sintering atmosphere, impurity content, grain size, and other extrinsic and intrinsic factors.
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 .
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