本論文為尋求鈷基合金粉末在雷射披覆作業之參數優化，採用田口實驗規劃法探討不同加工參數所造成的影響。其中因粉末材料性質與機台加工限制，加工參數選定與優化將是本文關注的目標；研究選定四個因子為：粉末流量、移動速度、雷射功率及Z軸抬升量來做實驗規劃，輸出結果為披覆厚度及稀釋率；優化前實驗披覆厚度約為2.65mm、稀釋率約為14%，優化參數後，厚度可達5.12mm，稀釋率降為4%；由田口分析果顯示提升披覆厚度及降低稀釋率的顯著因子為粉末流量，次要因子為移動速度，透過調變顯著及次要因子之參數可以最有效的達到所期待的目標；對田口實驗優化後的樣品進行顯微觀察，觀察到Stellite 6的典型結構，由樹枝狀的碳化鉻組織以及枝晶間的鈷固溶體組成，硬度量測得到穩定且高硬度，披覆層硬度為566±10 HV；透過實驗分析還發現到訊噪比與披覆厚度與稀釋率之間有著指數函數關係，吾人亦提出一簡易之計算方法，在選定加工參數後可估算出披覆厚度及稀釋率。

It is well known that direct energy deposition can be applied to metal 3D printer or cladding super alloy material on metal substrate。This paper reports a system integration result of a kW-class Yb-doped fiber laser and demonstrates the cladding of the Stellite 6 on the SKD61 substrate. Through the Taguchi Experiment, optimal set of cladding parameters to increase the thickness using Stellite 6 powder is found by changing powder feed rate, laser power, scan speed and Z-axis shifting. Analysis and discussion the microstructure and the hardness on the cladding material, dilution zone, heat-affected zone and the substrate are reported. Results can be directly used as a reference for subsequent engineering applications.

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