Scope of Friction Stir Processing in the development of Surface composites

 Friction stir processing is a solid-state method to develop composite especially surface composite. In this method, a non-consumable rotating tool is used to make a composite. The tool is allowed to be inserted inside the workpieces up to a certain depth to process the material. The tool will be rotating with a certain rotating velocity and also travel at a certain travel speed. With the rotation of the tool, the material will also stir and rotate which produces dynamics recrystallization in the material and forms fine grain materials.

Fig. Frictions stir processing

The development of fine grain material plays important in the changes of mechanical and material properties. It improves the hardness, strength, toughness, and wear resistance of the material. These are the important mechanical properties to make any mechanical component.  

To make composites with the help of FSP, grooves or holes need to be made on the upper layer of material to be processed. This can be done by any milling machine. Hard ceramic particles such as SiC, B4C, MoS2, Al2O3, Tio2 can be filled in this grooves. The first step is to close this groove with the pinless tool. Then a non-consuming rotating tool is employed over the work surface with the predecided rotational speed. The FSP tool consists of a pin and column. The pin part will penetrate inside the workpiece and force the material to stir along with it. Because of this, the material will go into intense plastic deformation and dynamics recrystallization happens with the processed material.

Fig. FSP tool

Material microstructure will change and very fine grain microstructure will obtain that reflects the increment of mechanical properties of the material. Further mixing of hard ceramics with matrix material improves its surface properties. Such as hardness, wear, and corrosion resistance increase the applications of these materials in different industries. Composite of light materials such as magnesium and aluminum alloy can replace the application of hard materials such as steel and tungsten in various requirements.

Author 

Dr. Hemendra Patle

Asso. Prof. - Department of Mechanical Engineering, NIIST, Bhopal