本研究使用CO2雷射，固定輸出功率35W，掃描速度2.286㎜/sec，雷射光束線寬設定為60μm條件下，在厚度為3㎜的單晶粒釔鋇銅氧超導塊材ab平面上掃描，由元素成份分析可知試片受雷射掃描過後，表面會生成一寬約250μm的Y2O3＋液相（CuO＋BaCuO2）區域，推測此區域受雷射掃描瞬間溫度超過1200℃，並在此區域外緣生成一寬約50μm的Y211＋液相區域，推測此區域受雷射掃描瞬間溫度超過1000℃，同時測量Y211＋液相區域外緣常溫下電阻，發現Y211＋液相區域往外10μm處，具超導特性的斜方晶Y123相轉變為不具超導特性的正方晶相，推測此區域受雷射掃描瞬間溫度超過600℃，其餘區域仍為具超導特性的斜方晶Y123相；透過300℃、24小時氧氣氣氛下充氧退火熱處理，不具超導特性的正方晶相又可回復為具超導特性的斜方晶相。使用前述雷射參數掃描過厚度為3㎜的單晶粒釔鋇銅氧超導塊材ab平面，會在ab平面上造成一寬約350μm的非超導區域，其餘區域藉由充氧退火處理仍可保持超導特性。

The high-temperature superconductor YBa2Cu3O7-δ（δ＜0.5） is processed by CO2 laser with 35W power, 2.286mm/sec scanning speed, and 60μm line width. The EDS results indicate that non-superconducting phase such as Y2O3 and liquid phase（CuO＋BaCuO2） were formed and Y211 and liquid phase were formed adjacent to laser treated area. It is conjecturable that the temperature of Y2O3 and liquid phase is above 1200℃ and the temperature of Y211 and liquid phase is above 1000℃ during laser ablating. At the position of 10µm away from the Y211 and liquid phase, the superconducting orthorhombic phase is converted to non-superconducting tetragonal phase by the electrical resistance measurement at room temperature. After oxygenation at 300℃ for 24 hours, the non-superconducting tetragonal phase is restored to superconducting orthorhombic phase.
In summary, these observations indicated a melting zone about 350μm in width and heat affected zone about 10μm in width by using the CO2 laser parameters described previously. And superconductivity of the heat affected zone could be restored by annealing in oxygen.

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