在本文中將探究雷射光斑大小對粉末床融合製造AlSi10Mg合金製程參數、機械性質、微觀結構之影響。以雷射光斑直徑(120 μm、 60 μm)進行獨立的線參數實驗，其結合雷射功率和掃描速率找出合適的製程條件，並定義各種線參數類型，探討光斑大小是如何影響加工參數圖及能量密度分布。結果表明，兩種光斑尺寸在搭配適當的加工參數下都成功地製造出無孔隙和缺陷的樣品，最高密度達99.96%。然而，拉伸樣品性能上有了輕微的轉變，在大光斑尺寸下表現出更高的伸長率，另一方面，在小光斑尺寸下則表現出更高的抗拉強度及降伏強度。此外，在X射線繞射分析儀中檢測到極強的α-Al (200) 峰值，此種結晶演化與兩種光斑尺寸的能量密度值相關；而繞射角偏移也驗證了雷射光斑尺寸間，因熱源機制所造成的晶粒結構差異。所有拉伸試樣的斷裂特徵都代表AlSi10Mg之韌性斷裂。
除此之外，本文也對於SiC顆粒與AlSi10Mg粉末混合，通過雷射粉末床熔合(LPBF)製造強化之鋁基複合材料進行研究，其研究針對SiC顆粒含量對LPBF加工複合材料的密度、微觀結構、顯微硬度、磨耗性能和拉伸性能作一系列之分析。發現鋁基複合材料中鋁枝晶被壓縮，晶界成長得更加明顯。由於熔融鋁基體與SiC顆粒之間的化學反應，形成了Al4SiC4針板狀、及豐富的Si多面晶核和Al-Si-C共晶物質。結果表明，耐磨性在SiC顆粒的參與下瞬間提高。然而，1.459 × 10-4 mm3N-1m-1的最低磨耗率以及約0.12的低摩擦係數發生於10重量百分比SiC混AlSi10Mg複合材料中。此材料展現出最優異的磨耗性能，是因為其硬度相對於未經碳化矽增強的鋁合金有效提高了約42%，且緻密度仍處於高水平。此外，磨損機制隨著碳化矽含量增加由磨粒磨損轉變為粘著磨損，主因是空洞及孔隙率的出現。不幸的是，隨著鋁基複合結構之演變，拉伸性能相對於鋁合金下降，而剪切唇區的消失，也象徵斷裂模式由韌性斷裂轉變為脆性斷裂。

The influences of laser spot size on mechanical properties and microstructure of AlSi10Mg alloy, fabricated by laser powder bed fusion, have been studied. Individual single track experiments were carried out by various laser spot diameters (120 μm, and 60 μm) to find out proper conditions combined with laser power and scanning speed, define various types of single track parameters, and investigate how the different spot size effect the processing window and energy density distribution. Using the proper parameters to fabricate the layer-layer samples, both the spot size parameters successfully obtained excellent results in dense cross section without pore and defect, the highest density about 99.96%. However, the stress-strain curve have slight transition in tensile performance, the higher elongation exhibit with 120 μm spot size condition, on the other hand, higher tensile strength and yield strength shown in spot size 60 μm. Strong α-Al (200) peak detected in X-ray diffraction with crystallization evolution correlated with the energy density values for both the spot sizes, and the diffraction angle shift indicate the heat source mechanism difference between the laser spot size condition. All the tensile specimens fracture characteristics represent the ductile fracture in as-built AlSi10Mg.
Besides, SiC particle were mixed with AlSi10Mg powder to fabricate reinforced aluminum matrix composites by the laser powder bed fusion (LPBF). The influence of starting SiC particle content on the density, microstructure, microhardness, wear performance and tensile properties of the LPBF-processed composite were investigated. Aluminum dendrites are compressed in the aluminum matrix composite and the grain boundaries grow more significantly. Due to the chemical reaction between molten Al-matrix and SiC particle, the products of Al4SiC4 needle-plate, Si faceted-grain, and Al-Si-C eutectic phase were formed. Wear mechanism transfer from abrasive wear to adhesive wear mainly due to pore and void appearance. The wear resistance suddenly improved with the participation of SiC particles. The lowest wear rate of 1.459 × 10-4 mm3N-1m-1 combined with the low coefficient of friction about 0.12 exhibit the excellent wear performance in the 10 wt.%SiC/AlSi10Mg composite, which due to its hardness effectively elevate about 42% over the un-reinforced AlSi10Mg alloy, while the densification level is still at a high grade. Unfortunately, the tensile properties decrease as the aluminum matrix composite structure becomes brittle. Fracture mode change from ductile fracture to brittle fracture because of disappearing of the shear lip zone.

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