Friction Stir Processing - Microforming

The trend of producing more compact/integrated systems demands miniaturization of the components involved. At the same time, the system should be capable of performing at par or sometimes better than those macro-systems conventionally available. Micro-Electromechanical-Systems (MEMS) are good example of such a push. In addition, requirements of miniaturization can be seen in a very diverse consumer product sectors, be it smaller and smaller cell phones and consumer electronics, to biomedical implants and tiny cameras for medical applications, to microturbines and so on. Components employed in MEMS and similar devices are generally made with traditional techniques such as etching, photolithography, electroless and electrochemical deposition, and micromachining. Conventional forming of macrocomponents, such as forging, is widely used because it can produce large volume of components in cost-efficient manner. Microforming has been difficult because of frictional effects associated with metal forming processing. For microcomponents the surface area/volume ratio is large and new concepts are needed to extend forming processes to micro-levels. Combination of FSP and superplasticity can be enabling technology for manufacturing of metallic microcomponents by replication. Figure 5 shows the enhanced replication of superplastic FSP 7075 Al alloy using a channel die of 1 mm length, 0.2 mm width and 0.5 mm depth. The better formability of superplastic material is quite evident. This technique will allow fabrication of microcomponents from common engineering alloys.