In conventional metal forming operations, we usually apply force to the metal to be worked upon using some form of a tool that could be a simple hammer blow or a power press impulse such as that used in drop forging. But today we will talk about an innovative method which is used in metal forming and can be said to be equivalent to hitting the work-piece onto the hammer rather than the other way round.
High Velocity Forming
As the name itself hints, HVF or high velocity forming refers to a set of techniques which are used for metal forming. These techniques could include methods such as explosive forming, electromagnetic forming and so forth. All these techniques involve imparting a high kinetic energy to the work piece by accelerating it to a highly velocity, before it is made to hit the appropriate die or made to undergo the process of plastic the formation.
I must also tell you that although this method seems very new, it was discovered more than 100 years ago and metals were being worked upon using HVF techniques as early as the 1930s. Due to the nature of the operations it would also be appropriate to name this technique as highly velocity deformation rather than high velocity formation.
One main advantage of using HVF techniques is that very complex shaped parts can be formed in a single operation, rather than carrying out a series of operations to achieve the same results via conventional forming techniques.
A wide variety of operations which are conventionally carried out using traditional methods can be done using highly velocity techniques, and these processes include those of extrusion, die-forging, punching, joining and so forth. The list of materials which can be formed using high velocity methods contains a wide variety of materials including magnesium, aluminium, zirconium, stainless steel, alloys steel etc.
Advantages of HVF
Highly velocity forming techniques have several advantages over conventional forming techniques, apart from reducing the number of processes required in manufacturing.
The strain distribution is much more uniform in a single operation of HVF as compared to conventional forming techniques. This results in making it easy to produce complex shapes without inducing unnecessary strains in the material.
Since the basic principle of a highly velocity formation technique is quite opposite to that of a conventional forming technique, the tools and other equipment used in the process has quite lightweight compact relatively speaking.
High velocity techniques can be used to improvise upon various joining methods such as say for example fusion welding. Impact welding using highly velocity techniques can produce much better results than the conventional fusion welding techniques
This article provides a broad overview of the highly velocity forming techniques used in manufacturing technology. It must be stated at this stage that the entire topic of HVF is too broad and deep to be covered in a single article, yet the above material should suffice to give a general understanding to the reader about the same. We might take up various aspects of high velocity forming in our later articles.