本文的目的是探討利用雷射線熱源切割玻璃引發熱應力而達到材料破壞之研究，研究中使用CO2雷射，利用高斯分佈之移動式線熱源加熱在玻璃表面，達到切割動作。在有限元素分析中，考慮材料之熱彈性行為，採用熱機非偶合(Uncoupled thermal-mechanical analysis)的模式計算雷射切割所引發的溫度與暫態熱應力，以了解應力分佈對於裂紋之影響，且分別針對功率、切削速度與偏轉角度等製程參數進行討論，並規劃一系列實驗與分析結果作比較。

　　研究結果顯示，隨著偏轉角度不同在玻璃表面產生的破壞裂紋與切割品質皆不同，其裂紋隨著溫度擴散方向開始成長，且隨著偏轉角度增加破壞不再是張裂模式破壞。而在偏轉角度0度時因為深度方向之熱擴散不均勻會有切屑產生。

　　The object of this thesis is to study the thermal stress of the glass plate in laser cutting. A high power CO2 laser with Gaussian beam mode was used as a moving line shape heat source on a soda-lime glass plate.
In the analysis of the thermal stress problems of soda-lime glass plate,the transient thermal was simulated numerically. The non-linear finite element software, ABAQUS, was used to simulate the thermal stress problem for an uncoupled thermal-mechanical system in three-dimensional domain. The temperatures, transient thermal stress during the laser cutting process were calculated. The process parameters affecting the stress value were also investigated.

　　It was shown that the crack and cutting quality was different on the glass surface along with the different rotating angle, the crack spreaded along with thermal diffusion direction and increased with rotating angle, and the fracture mode was not the opening mode. As the rotating angle being 0 degree, the chip formation is along with the depth direction due to the thermal diffusion asymmetry.

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