4 октября, 2015 
Pokraskin The surface condition ofthe adherents is one factor which has the greatest impact on the quality and durability of adhesively bonded joints. Therefore, both in the literature and in adhesive manufacturers data sheets it is strongly recommended
that the adherent surfaces are cleaned and carefully prepared prior to bonding. Only in few cases where the type and amount of contamination are predefined and the adhesive is designed to tolerate this specific degree of contamination, can bonding be carried out without further cleaning procedures. This applies especially to the bonding of steel sheets in body-in-white construction. Here, hot-setting adhesives with a special formulation are used that are capable of building up high-strength adhesion with long-term durability on oil-protected surfaces — ‘against all the rules’.
This requires the adhesive manufacturers and users, in cooperation with the steelmakers and oil producers, to take appropriate measures to ensure the compatibility of lubricants with the adhesive systems. In the majority of other fields of application a thorough surface preparation, including cleaning and degreasing, must be performed before adhesive bonding.
The purpose of cleaning is to remove dust, grease, oil, rust, scale and miscellaneous dirt from the surface of the adherents. A variety of cleansing agents such as organic solvents and water-miscible detergents is commonly available. Polar hydrocarbons (e. g. esters, ketones, alcohols) are the material of choice for degreasing, but in open facilities the safety and health of the workers, as well as environmental precautions, must be considered when handling these hazardous substances. Acetone is often used because it has a good balance of cleaning capability and comparatively low environmental concern, although fire-protection measures must be taken due to its liability to ignite. This applies especially when processing cannot be carried out in a hermetically closed circuit.
The following cleaning methods are used in industrial manufacture [10]:
• mechanical cleaning (e. g. sanding or grit blasting)
• solvent wipe
• immersion in an ultrasonic solvent bath
• vapor degreasing with solvents
• washing with aqueous solutions
• high-pressure water steam cleaning
The most common surface preparation methods are discussed briefly in the following sections.
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