Laser Induced Surface Improvement for Superior Wear Resistance in Extreme Conditions

The objective of this Phase I project is to evaluate the use of novel Laser Induced Surface Improvement (LISI) techniques to provide surface modification to substrate materials which will provide superior wear resistance in extreme conditions. The specific application of interest is the hypersonic metal-to-metal contact that occurs at high speed test track facilities that can and has lead to catastrophic failure of the guide rail system. Our proposal will modify the surface of the rail material (AISI 1080 steel) to provide an integral alloyed surface with superior wear resistant capabilities. In Phase I we will identify the most promising precursor alloy materials and apply them with the LISI process to test coupons for wear evaluation. Parametric studies of wear response to various LISI process parameters will be performed to find the optimum alloy materials and process for this application. Finally we will apply the process to a section of test track rail to prove the ability to process all wear bearing surfaces (top, sides, and bottom of rail) in a controlled and satisfactory manner. In Phase II we will engineer a delivery system to allow in-situ application of the LISI process to rails in the field. BENEFIT: Extreme conditions for wear are found in many commercial applications. While the high speed test track is an extreme case due to the high speeds encountered, it does have relatively low loads. It is actually the product of pressure and velocity that induces the wear and there are many commercial applications that have lower velocity but much higher pressures (and thus similar Pv quantities as the present application). It is therefore expected that this process can be used in many other high wear situations. The fact that we are working on rail geometry lends itself immediately for use on other rail geometries including train, crane, presses, etc.