近年來發展的金屬積層製造將帶來創新的加工方式，透過加法製程，將材料以層層堆疊的方式結合，因此將不受限於成型的複雜度。選擇性雷射燒熔(Selective Laser Melting, SLM)技術為目前金屬積層製造中的重點技術，利用雷射做為加工熱源，使金屬粉末材料熔融並快速冷卻聚合成型，不需經過後續加工處理就能夠有良好的精度及表面粗糙度，並且達到接近完全緻密的物件。
本研究將使用氣霧法製程之AlSi10Mg合金粉末，以選擇性雷射燒熔製程進行參數研究，過程中將探討雷射功率、粉末鋪層厚度、掃描速度、掃描間距等製程參數的改變對於成型物件的緻密度影響，並且比較製程前後的微觀結構及熱處理前後的機械性質改變，找出適當的製程參數區間。
研究結果顯示，在雷射功率360W及鋪層厚度0.05mm定義能量密度區間：低於40 J/mm^3為能量不足區間，參數平均相對密度值為96.03%；40至75 J/mm^3為能量適當區間，參數平均相對密度值為99.58%；超過75 J/mm^3為能量過大區間，參數平均相對密度值為99.15%。在能量密度值55 J/mm^3下的參數，其相對密度值皆大於99.8%，且表現出最優異的穩定性，因此定義為最佳能量密度值，並以此能量密度值參數(P=360W, t=0.05mm, s=550mm/s, h=0.24mm)測得最佳機械性質，與傳統鑄造方式相比，拉伸強度提升68%；降伏強度提升45%；伸長率提升13%；硬度提升62%，展示出SLM製程下的快速冷卻因素使晶粒細化產生優異的機械性質。

In recent years, the development of metal additive manufacturing (MAM) has brought an innovative progress. Through the additive manufacturing process, the material will be stacked in layers, it will not be limited by the complexity of molding. Selective Laser Melting (SLM) technology is the key technology for the current metal manufacturing. It uses laser as the processing heat source, making the metal powder melt and rapidly cooling. SLM process presents great potential applications in the fabrication of complex parts with fine microstructure. In this study, AlSi10Mg alloy powder obtained by gas atomization process is used to study the parameters of SLM process. The effects of objective of this research is to investigate process parameters such as laser power, layer thickness, scanning speed and hatching distance on the relative density on the object. We then compare the microstructure through the SLM process and mechanical properties before and after heat treatment to determine the appropriate process parameters interval. Results show that the average relative density of the parameters is 96.03%, 99.58%, and 99.15%, with the energy density less than 40 J/mm^3, 40 to 75 J/mm^3, and more than 75 J/mm^3, respectively. Results also show that at the energy density value of 55 J/mm^3, the relative density values are greater than 99.8% and exhibit the optimal stability; therefore, defined as the optimum energy density values. The optimum mechanical properties were measured with this energy density parameter (P = 360 W, t = 0.05 mm, s = 550 mm/s, h = 0.24 mm). Compared with the traditional casting method, SLM helps increase tensile strength by 68%, yield strength by 45%; elongation by 13%, and hardness by 62%. The result demonstrates that the rapid cooling factor under the SLM process produces fine grain refinement to achieve excellent mechanical properties.

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