Disadvantages Of Welding

1.0 INTRODUCTION TOWARDS WELDING ACTIVITIES

Forming is to give form or shape, to make up, to take form, and to take a definite form, shape or arrangement. Welding is the process of joining two or more materials together permanently, usually metals, by heat or pressure or maybe both. A weld is made when separate pieces of material to be joined combine and form one piece when heated to a temperature high enough to cause softening or melting. Filler material is usually added to strengthen the joint. Welding is a dependable, efficient and cost-effective method for permanently joining same metals. It means, it can weld steel to steel or aluminum to aluminum, however it cannot weld steel to aluminum using old welding processes. Welding is used

All of the processes are viable ways to join two similar or dissimilar metals, each with its own advantages and disadvantages including equipment, size and shape of material to be welded, temperature ranges, welding times and relevant applications. The common techniques (in brief) are:

a) Roll bonding – creates a weld between two or more sheets or plates, in intimate contact, by sending them through a rolling mill, which will cause severe plastic deformation that results in bonding.

b) Diffusion bonding – is a process by which a joint can be achieved between similar and dissimilar metals, by the diffusion of atoms across the interface, based on the bonding pressure and heat applied over time. Temperature should be from 0.5 to 0.8 of the melting point of the most fusible metal.

c) Ultrasonic welding – is a solid-state process where a joint is formed through the use of vibratory energy.

d) Friction welding – creates a joint, where the relative motion of the two interfaces of the materials produces the heat for welding. Mechanical energy is directly converted to thermal energy without