Investigation into development of rapid heat ablation process using hot tool

Abstract

Rapid prototyping and manufacturing (RPM) technologies have been widely adopted by the industry, because of the potential of these technologies to rapidly fabricate three-dimensional parts with geometrical complexity from a CAD model in a CAD/CAM environment. Present RPM technologies are classified into laminating and machining processes by fabrication method. Even though the laminating process has several advantages such as easy fabrication of complex shape, the process is not widely used in industry. Post-processing resulting from the nature of layer-by-layer building process is extremely labor-intensive and time-consuming. Compared with the laminating process, the machining process leads to better surface finish and dimensional accuracy. However, the machining processes have had the fundamental disadvantages of unsatisfactory cutting mechanisms: too much time has been required to cut a given part. Therefore, a new cutting mechanism is needed to resolve these problems. In this thesis, a new rapid manufacturing process, a rapid heat ablation (RHA) process using the hot tool has been developed to overcome some fundamental disadvantages, such as excessive cutting time and leftover material caused by the cutting mechanism. Because of a unique mechanism to remove material, the proposed RHA process has several advantageous features. One is a rapid shaping of a rough ablation due to the high rate and large amount of material removal. A second has to do with the fact that it leaves little or no remaining material as it melts or decomposes material after ablation. Finally, it accomplishes both a rough and fine ablation without a change of tools. The use of this hot tool in a rough ablation process enables a one-time ablation of the workpiece from a raw shape into an actual part because of its heat ablation characteristics. In order to realize the principle of heat ablation, the RHA apparatus is integrated. The RHA process employs a synchronized three-axis table t...