Hardness Test of Ceramic materials
Hardness is a measure of a materials resistance to penetration by a hard indenter of defined geometry and loaded in prescribed manner, it is one of the most frequently measured properties of a ceramic
Hardness value helps to characterize resistance to abrasives or wear, resistance to plastic deformation, modulus of elasticity, yield strength, ductility, and fracture toughness. It is necessary for cutting tools, wear and abrasion-resistant parts, prosthetic hip joint balls and sockets, optical lens glasses, ballistic armor, molds and dies, valves, and seals.
The hardness of a ceramic is defined by its chemical composition, including porosity, grain size, and grain-boundary phases. There are many different hardness tests and each gives a different number.
The Methods and Process of Hardness Testing There are multiple measurements of hardness, including scratch hardness, indentation hardness, and rebound hardness. Each type of measurement is based on an individual measurement scale, however, conversion between scales is possible for practical purposes. Indentation tests are a common method of testing the hardness of a ceramic material. Indentation is a straight forward test of penetrating a given material with an indenter under a pre-defined indentation load, then measuring the resulting indentation. Indenters come in a variety of different shapes and sizes as in figure 15 , and the load can be set for nano, micro, or macro indentation ranges, so as to specify the range of mechanical properties that will be tested. The general concept behind the measurement is very similar: the harder
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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