本研究之創新為在既有金屬3D列印製程上建立不同金屬為對應基材，並於此基材上堆疊出建立的特徵，進而分析此特徵之尺寸精度及表面完整性。其中利用田口實驗方法 (Taguchi Methods, L9 Test array) 與變異數分析 (ANOVA)，找出鈦合金 (Ti-6Al-4V) 與不鏽鋼 (SST316L) 兩種合金材料透過選擇性雷射熔化 (SLM) 分別燒結於鈦 (Commercial pure, G1) 與不鏽鋼 (AISI316) 異質金屬工件之最佳製程參數組合。本實驗之參數組合參考三種可變因子、三水平 (雷射瓦數：100-200 W；脈衝時間：50-100 μs；焦點間距：35-70 μm) 的田口L9直交表，固定因子為:雷射掃描速度 (Ti-6Al-4V：70 mm/s，SST316L：220 mm/s) 、堆疊層厚 (Ti-6Al-4V：50 μm，SST316L：30 μm)、掃描間距 (Ti-6Al-4V：110 μm，SST316L：125 μm)。於雷射熔化製程後，觀察九種參數在密度、空孔率、尺寸變異 （直徑和高度）、拉伸應力等各項定量指標在工件上的變化，並從中找出最佳雷射熔化參數；而定性指標為顯微硬度、顯微組織、合金成分變異。前者利用統計分析方法中的變異數分析 (ANOVA)，找出各項指標中之顯著因子；後者則利用金相顯微鏡觀察、分析雷射熔合粉末之金屬顯微組織變化，最後將各指標進行分析與結論。

This study presents a state-of-the-art concept to layer metallic powder on a metallic carrier which is in different constituent. This may inducing a new application on repairing or composing metallic features in a composite forms. The preferred selective laser melting (SLM) process parameters for Ti alloy (Ti-6Al-4V) and stainless steel (SST316L) stacking onto heterogeneous metals Titanium (commercial pure, G1) and stainless steel (AISI316) respectively are examining by Taguchi Method (L9 Test array) and ANOVA. The parameter combinations were implemented by Taguchi L9 orthogonal array of three-factor model with fixed factors, such as laser scanning speed (Ti: 570 mm/s, SST316L: 220 mm/s), layer thickness (Ti: 50 μm, SST316L: 30 μm) and scanning spacing (Ti: 110 μm, SST316 L: 125 μm) . After SLM process, this study disclosed the best laser melting parameters by quantitatively observing the indexes, such as density, porosity, dimensional deviations (diameter and height) and tensile stress. etc., upon nine types of process parameters. Moreover, qualitative indexes includes micro-hardness, metallographic analysis and element changes in alloy. The former was performed by ANOVA to find out main factors within all indexes and the latter was executed by metallographic examination.

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