College of Engineering and Polymer Science

Date of Last Revision

2021-09-14 08:34:03


Mechanical Engineering

Honors Course


Number of Credits


Degree Name

Bachelor of Science

Date of Expected Graduation

Spring 2021


A novel surface treatment, laser assisted ultrasonic nanocrystal surface modification (LA-UNSM), has proved effective in increasing surface hardness, and fatigue life. The objective of this research is to determine the effectiveness of this process on components created with additive manufacturing. To accomplish this, we investigated the effectiveness of LA-UNSM treatment on aluminum, a common 3d printed metal, and the effectiveness of LA-UNSM processing on 3d printed titanium. We first conducted our own literature review to assess the practicality of using this same treatment on aluminum. We then treated traditionally manufactured aluminum at varying levels of laser intensity to determine if this process was valid for aluminum. The low recrystallization temperature of aluminum was noted as a concern. Proceeding with our plan we treated aluminum samples at varying levels of laser power while using the same UNSM processing parameters. Hardness tests were conducted to determine the effect of the treatment, from this data a conclusive trend was difficult to identify. In looking into the effectiveness of this process on 3d printed material, we used a sample of 3d printed titanium provided to us by colleagues. We compared the effectiveness of LA-UNSM treatments on traditionally produced titanium to the 3d printed sample using the same processing parameters with each. These samples we compared with hardness tests and microscopic surface inspection to evaluate the roughness and hardness of the samples before and after processing. These results confirmed the effectiveness of LA-UNSM treatments on titanium materials as well as demonstrated the possibility to use this process on 3d printed surfaces. Our exploration of the effects of LA-UNSM processing on titanium, of conventional and 3d printed manufacture, shows the LA-UNSM process works on 3d printed material as well as on traditional manufactured surfaces. The investigation of the effects of LA-UNSM treatment on aluminum was less clear. There was an improvement of the surface hardness with treatment, but further investigation is required into the effect of the laser alone on the surface

Research Sponsor

Dr. Yalin Dong

First Reader

Dr. Guo-Xiang Wang

Second Reader

Dr. Siamak Farhad

Honors Faculty Advisor

Dr. Scott Sawyer



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