What are Fasteners? Types of Fasteners.

From the regular household appliances we use in our day to day life to the high tech gizmos we use have a common component in them – A Fastener. Fasteners though not visualized by us directly or even thought of, play a vital role in our day to day life. Be it from, holding the chairs and tables we sit on; be it the automobiles we travel; every inch of what we use is held in place by means of a Fastener.

We mainly use a fastener for a non-permanent joint. What do we mean by a non-permanent joint? A joint that can be removed or dismantled without the destruction or damage of the joining components can be termed as a non-permanent joint. A welding joint or riveted joint can be termed as a permanent joint, which if required to be removed tends to damage or destruct both the joining components as well as the joint itself.

Types of Joints

This is how a fastener terminology looks like.

fasternerterminology

The basis of a fastener is basically a screw thread. – The male part is basically the screw with an external thread and the female part is a hole with an internal thread. The female part can also be a nut. Here are some ways by which a fastened joint can be created.

types of fastened joints

Based on the application area of the fastener, the head portion of the fastener is available in various shapes and sizes as shown below.

types of fastener heads

Here is a list of materials used for manufacturing of Fasteners:

Carbon steel: This is the most commonly used material for fasteners.

Alloy Steel

Stainless Steel

Inconel Stainless steel

Titanium: This is mostly used in aircraft application fasteners.

Aluminium: This is used in areas of very light loads and application requiring reduction in weight.

Apart from using the above materials as fasteners, certain types of coatings are also provided on the fasteners in order to improve their performance characteristics. The main purpose of coating is to improve the corrosion resistance characteristics of the fasteners. The various types of coatings available for the fasteners are

Cadmium Plating: used mainly for aerospace applications

Zinc Plating

Phosphate Plating

Chromium plating

Silver Plating

Black Oxidizing

Nickel plating