Simulation-based design of laser-based free forming process control

A laser-based, free-forming process manufactures products without a mold and die. This process is most beneficial to expensive products because the high cost is often a result of long processing times and excessive waste material. In the free-forming process, material is directly deposited layer-by-layer onto the part, producing little to no waste. As a result, production costs are significantly reduced. However, because these parts are created layer-by-layer, their quality must be closely controlled during the process, avoiding the unnecessary cost of continuing to produce unacceptable products. Furthermore, incomplete products may be rejected when the process is terminated. A process controller, therefore, is necessary to complete this process with little or no defects. This paper presents a simulation-based design of laser-based, free-forming process controller. The relationships are defined between process characteristics and three variables: laser power, translation speed, and powder flow rate. These relationships are then used to design the process controller. Experimental results from each step are also presented.