ECAE is a method of inducing large plastic deformation to materials without changing the size or general shape of the billet. There are some interesting properties that arise from this extrusion process, such as increased material strength, hardness, and many other case dependent features. The extrusion process is carried out at temperatures ranging from 77K to 1500K, depending on the material and desired results. It is accomplished by forcing a billet of material through two intersecting channels of only slightly different dimensions. The angle can be chosen between 0 and 90 degrees to provide a varied amount of strain. As the billet passes the turn, the material must shear in a fashion unique to this process.
The simple shear imparted to the material at the intersection of the two channels ensures the material will endure dramatic but uniform deformation after the extrusion, and yet the basic size and shape of the billet remains unchanged. The billets can be processed with multiple passes through the dies to further cold work the material. Also, varying the entry orientation of the billet with successive passes can further vary the results. This process holds much promise for the higher material specification demands of tomorrow.