本研究以高溫且有高吸收率的太陽能吸收塗層為目標。首先利用高速火焰熔射(High-velocity oxygen fuel, HVOF)製程來噴塗碳化鎢/鈷的塗層，在塗層表面再用雷射雕刻製程改變表面微結構形貌。另利用田口方法，建立直交表來配置雷射雕刻製程實驗參數，實驗參數包括塗層厚度、雷射功率、雷射雕刻速度、雕刻間距、雷射頻率。當完成不同實驗參數樣本，可於因子效應分析與變異分析中找出最佳製程參數。本研究根據田口方法所建議之最佳製程參數來進行進一步的微調，從實驗結果得知吸收率最高可達96.5%。從塗層形貌、材料元素分析與晶相結構分析，得知塗層表面的孔洞結構與雷射雕刻於碳化鎢/鈷所產生的晶相為造成高吸收率的原因。

This study is aimed at development of high-temperature and high-absorptance thin film coating on solar absorber. Firstly, a multi-layers film coating structure made of tungsten carbide/cobalt is fabricated by using high-velocity oxygen fuel (HVOF) technology. Secondly, laser engraving technology is utilized to make micro-scale structures on the tungsten carbide/cobalt thin film. The fabrication parameters of laser engraving process, such as film thickness, engraving power, engraving velocity, frequency of laser, and pitch of engraving, is tested by experiments on solar energy absorptance and morphology observation. Based on the experiments conducted, the laser engraving parameters have been optimized by means of the Taguchi method with orthogonal array of the samples. Results show that by properly adjusting the combination of the parameters, the absorptance of the solar energy reaches 96.5% in the experiments. Further crystalline phase material element analysis and structural analysis show that the high absorptance is mainly caused by the morphology of the micro-scale pore structures and the compounds formed on the surface of the thin film after the laser engraving.

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