Introduction Wear is the surface damage or removal of material from one or both of two solid surfaces in a sliding, rolling, or impact motion relative to one another. In most cases, wear occurs through surface interactions at asperities. Wear, as friction, is not a material property, it is a system response.
Types of Wear Mechanisms
Wear occurs by mechanical and/or chemical means and is generally accelerated by frictional heating (or thermal means). Wear includes six principal, quite distinct phenomena that have only one thing in common: the removal of solid material from rubbing surfaces.
These are: (1) adhesive; (2) abrasive; (3) fatigue; (4) impact by erosion and percussion; (5) chemical (or corrosive); and (6) electrical arc-induced wear.
Adhesive Wear Adhesive wear occurs when two nominally flat solid bodies are in sliding contact, whether lubricated or not. Adhesion (or bonding) occurs at the asperity contacts at the interface, and these contacts are sheared by sliding, which may result in the detachment of a fragment from one surface and the attachment to the other surface. As the sliding continues, the transferred fragments may come off the surface on which they are transferred and be transferred back to the original surface.
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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