In many of the industrial applications today, composite material plays an important role among the structural materials in use. Composite materials offer the most effective solution in all applications where the strength-to-weight ratio is of critical significance. Hence, they hold a place of importance in aerospace industry, marine technology and race cars and are used in manufacture and repair of structural components of heavy structures such as buildings, bridges etc.
Selecting the Right Adhesive Kind for Composite Fabrication
Joining components of such composites to one another or to other substrates like metal, plastic and wood is one of the important steps in the manufacture of composite structures. Adhesive bonding is a highly powerful and effective technique for joining of composite materials due to their high strength-to-weight ratio and great resistance to fatigue. However, the adhesive selection process is not very easy as there is no single solution that fits all. Several factors need to be considered such as type and class of the substrates, cure times, methods of application and the anticipated stresses and environments the composite joint will have to encounter. Cost of the adhesive may also be a deciding factor during the selection process. Composite materials use high heat UV resin-matrix systems and this has necessitated the creation of equally temperature stable and compatible adhesive solutions. Epoxy adhesives are used commonly for composite fabrications in addition to PU or MS polymers. To meet the requirements of such applications the adhesives need to possess one or more of the features; such as chemical and fluid resistance, endurance to environmental stresses, fatigue, strength, robustness and the capability to wet the substrate.
Usage of Adhesives in Plastic Fabrications
Selecting the right adhesive for your plastic fabrication can also get quite overwhelming considering the multitude of options available. However, this task can be made a little simpler if you have answers to certain simple questions. They pertain to the type of plastic substrates that have to be bonded, their assembly conditions, desired cure time or viscosity and so on. The physical attributes of the plastics have to be understood; some of them like polypropylene and polyethylene will fail to bond together irrespective of the adhesive used. Another factor is the major difference in thermal expansion of varied plastics. The expansion and contraction at the joints of dissimilar plastics will be varied to a great degree depending upon the type of plastics involved. This places huge stress at that area and hence an adhesive that can withstand such a stress will need to be used. The conditions of humidity and the amount of heat required in the fabrication area alongside the temperature of the components of the assembly are also of crucial significance. The adhesives normally used in such applications include the reactive adhesives or solvent cements with greater viscosity.
On a Concluding Note
Adhesives suited to every plastic and composite fabrication are available in the market. It is essential to know the details of each to decide which suits your application the best. If you use the right adhesive then the bonding for your application is sure to last for long times to come.