Faculty Advisor

Professor Christopher A. Brown

Faculty Advisor

Professor Kevin (Yiming) Rong

Faculty Advisor

Professor William C. S. Weir

Faculty Advisor

Mr. Carmine Sammarco

Faculty Advisor

Dr. David Skinner




The goal of this dissertation is to develop a model relating LENSâ„¢ process parameters to deposited thickness, incorporating the effect of substrate heating. A design review was carried out, adapting the technique of functional decomposition borrowed from axiomatic design. The review revealed that coupling between the laser path and laser power caused substrate heating. The material delivery mechanism was modeled and verified using experimental data. It was used in the derivation of the average deposition model which predicted deposition based on build parameters, but did not incorporate substrate heating. The average deposition model appeared capable of predicting deposited thickness for single line, 1- layer and 2-layer builds, performing best for the 1- layer builds which were built under essentially isothermal conditions. This model was extended to incorporate the effect of substrate heating, estimated using an energy partition approach. The energy used for substrate heating was modeled as a series of timed heating events from an instantaneous point heat source along the path of the laser. The result was called the spatial deposition model, and was verified using the same set of experimental data. The model appeared capable of predicting deposited thickness for single line, 1- layer and 2- layer builds and was able to predict the characteristic temperature rise near the borders as the laser reversed direction.


Worcester Polytechnic Institute

Degree Name



Manufacturing Engineering

Project Type


Date Accepted





rapid prototyping, solid freeform fabrication, LENS, laser engineered net shaping, laser, titanium, Pulsed laser deposition, Titanium, Prototypes, Engineering