Comprehensive knowledge of the use of adhesives

Advantages and disadvantages of adhesives

Adhesives have many advantages and disadvantages when using each of the bonding methods.

The following are the most important advantages and disadvantages.

advantage

Shortcomings

Adhesive has continuity on the joint surface, making its stress distribution uniform. (Stress concentration should be avoided at certain locations.) Most adhesives have good mechanical damping properties (sound and vibration damping). In many cases, joints can be assembled at relatively low temperatures to prevent gas from leaking and form a reliable seal. The material can be adhesively bonded. Adhesive bonding reduces the weight of the positive structure. Compared to other joining techniques, the adhesive bonding method is quite simple. The joint strength is usually lower than other joining techniques. Under peeling and tearing stress, the adhesive Most of the agents are not very good. After solidification, they can reach full strength. Some chemicals may affect the adhesive. Most of the adhesives are not suitable for joining. It is often difficult to separate the joined parts by the method of not damaging them. It is often difficult to avoid the physical health of solvents and other chemicals. harm
2. The correct design of adhesive joints

Joints may be based on a combination of tension, pressure, shear or tear force.

The adhesive has the greatest strength under shear and pressure, but is relatively unfavorable under peel and tear forces (see Figures 1 to 5). Therefore, the joint needs to be designed so as to reduce or avoid tearing or peeling force.

Figures 6 and 7 show that two common types of joints can be designed using the "wrong" method (based on destructive tearing force) and how they can be redesigned with improved performance.

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