Surface preparation or treatment is defined as one or a series of operations including cleaning, removal of loose material, and physical and/ or chemical modification of a surface to which an adhesive is applied for the purpose of bonding. In plastics bonding, surface preparation is aimed at increasing the surface polarity, improving surface wettability, and creating sites for adhesive bonding. Metal surfaces are typically covered with oxide layers, rendering the surface highly polar and fit for good adhesive bonding.
The following techniques are typically used as practices for good surface preparation:
Degreasing Degreasing is carried out in order to remove any loosely held dirt or other contaminants from the surface. Surfaces can be degreased using volatile solvents such as toluene, acetone, methyl ethyl ketone, methyl alcohol, isopropyl alcohol and trichloroethylene. However, kindly make sure that all the environmental, health and safety regulations are met prior to selecting a solvent. The most common methods used, typically include the three main steps:
1. Vapor degrease/ clean/rinse the parts with the appropriate solvents. 2. Immerse the substrates in a fresh bath of solvent for the wash and follow by an immersion in the second tank for a rinse. 3. Cleaning and drying the substrate post the degreasing.
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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