Improved Kolsky-bar design for mechanical characterization of materials at high strain rates

A Kolsky apparatus with numerous modifications has been designed for mechanical characterization of materials at high strain rates. These modifications include employing a highly precise optical table, pillow blocks with Frelon®-coated linear bearings as bar supports and a laser system for better precision bar alignment, etc. In addition, the striker bars were coated with Teflon® to minimize the friction with the gun barrel after removal of the conventional plastic sabots. This new design significantly simplifies the alignment process, improving the final alignment and calibration in the bar system; both are critical for validity and accuracy of the resulting data. An example of a dynamic experiment on a 6061 aluminum specimen by using this newly designed Kolsky bar is also presented.