本研究透過雷射箔材列印（Laser Foil Printing, LFP）技術，探討鋯基金屬玻璃（Zr₆₅.₇Cu₁₅.₆Ni₁₁.₇Al₃.₇Ti₃.₃）在 Zr702 基材上的熱行為，並利用熱成像技術分析雷射掃描策略與熔池冷卻速率之間的關係，特別關注其對熱行為與非晶穩定性的關鍵影響。實驗中使用中波長紅外線（MWIR）攝影機，即時監測熔池與熱影響區（HAZ）的溫度變化，以定量評估冷卻速率與熱演化過程；同時輔以有限元素模擬，以解析熔池溫度梯度與熱傳行為。研究核心在於探討維持非晶結構並避免結晶所需的冷卻條件，並針對連續焊接與離散焊接兩種掃描策略進行比較。後續材料表徵則包括 X 光繞射（XRD）、能量散射光譜（EDS）與顯微硬度測試，用以評估非晶保持、成分分布與機械性能。
研究結果顯示，連續焊接雖可形成較大且較深的熔池，但因能量輸入持續，導致顯著熱累積，使熱影響區擴大，冷卻速率逐漸降低，並在第三層出現部分結晶。相較之下，離散焊接透過局部且間歇性的能量輸入，能維持較高且穩定的冷卻速率，有效抑制熱累積並縮小熱影響區，因此在多層堆疊中均能保持完整的非晶結構。成分分析進一步顯示，隨層數增加，鋯含量逐漸下降而鎳與銅含量上升，但非晶穩定性主要仍受冷卻動態控制。顯微硬度測試亦證實離散焊接試樣的硬度顯著優於連續焊接。
本研究證明雷射掃描策略與熱動力學在金屬玻璃 LFP 製程中具有決定性影響。離散焊接展現出更佳的熱控制能力、非晶保持效果與機械性能，成功建立明確的「製程–結構–性質」關聯，並為推動高性能塊狀金屬玻璃的積層製造提供了重要依據。

This study employs the Laser Foil Printing (LFP) technique to investigate the thermal behavior of zirconium-based metallic glass (Zr₆₅.₇Cu₁₅.₆Ni₁₁.₇Al₃.₇Ti₃.₃)deposited on Zr702 substrates. In-situ thermography was applied to establish the relationship between laser scanning strategies and melt-pool cooling rates, with particular focus on their influence on thermal dynamics and amorphous stability. A mid-wavelength infrared (MWIR) camera was used to monitor the temperature evolution of the melt pool and heat-affected zone (HAZ) in real time, enabling quantitative evaluation of cooling rates and thermal history. Finite element simulations were further conducted to analyze melt pool temperature gradients and heat transfer behavior. The study emphasizes the cooling conditions required for amorphous retention and crystallization avoidance, and compares continuous and discrete welding strategies. Post-process characterization, including X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and microhardness testing, was carried out to assess amorphous stability, compositional distribution, and mechanical properties.
The results indicate that continuous welding produces larger and deeper melt pools than discrete welding, but sustained energy input leads to significant heat accumulation, broader HAZ, gradually reduced cooling rates, and partial crystallization in the third layer from the substrate. In contrast, discrete welding introduces localized and intermittent energy input, achieving higher and more stable cooling rates, effectively suppressing heat accumulation and minimizing the HAZ. As a result, fully amorphous structures were retained across multiple layers. Compositional analysis further revealed a gradual decrease in zirconium content and enrichment of nickel and copper with increasing build height, although amorphous stability was primarily governed by cooling dynamics. Microhardness testing confirmed the superior hardness of samples from discrete welding compared with continuous welding.
This study demonstrates the role of laser scanning strategy and thermal dynamics in the LFP processing of metallic glass. Discrete welding provides superior thermal control, more reliable amorphous retention, and improved mechanical properties, establishing a clear process–structure–property relationship and offering practical guidelines for advancing the additive manufacturing of high-performance bulk metallic glasses.

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