本研究旨模擬使用銅粉-聚乳酸（PLA）複合線材3D列印金屬零件的脫脂過程及燒結過程。與傳統利用純金屬粉末的3D金屬列印方法相比，利用金屬粉末-PLA複合線材製造金屬零件極大地降低了製造金屬零件的成本。此製造方法裡，脫脂和燒結過程對於製造金屬零件的性能有著關鍵影響。本研究使用質量百分比為90%銅粉及10%PLA的線材製造試樣，在3D列印完成後，列印品被放置在高溫窯中按照預設的溫度進行脫脂及燒結反應。在脫脂過程中，粘結劑PLA將被分解後燃燒，從試樣中移除。之後，溫度在燒結過程中被提高至低於銅的熔點但是足夠高使得銅粒子能夠進行燒結反應。一般情況下，在整個製造過程中所需的時間超過24小時，不包括3D列印時間。基於開發的模型，本研究對整個過程進行數值模擬，試圖提高製造效率。本研究的目的是開發一個完整而新穎的數值模塊，用於金屬列印零件的熱處理過程，助於理解在脫脂反應中PLA去除和燒結反應的物理本質。

The current study aims to develop a theoretical model for simulation of thermal debinding and sintering processes for 3D printing metallic parts using copper polyacrylamide (PLA) composite filaments. Compared to the traditional 3D metal printing methods employing pure metal powders, this approach greatly reduces the cost of manufacturing the metallic parts. In this approach, the debinding and sintering processes play a crucial role in achieving desired properties of metallic parts fabricated. After being printed, the printed specimen is placed in a high-temperature kiln where it experiences debinding and sintering processes to form solid metal by following prescribed recipes Filament with a mass composition of 90% copper powder and 10% of PLA is used to print the specimens. In the thermal debinding process, the binder PLA is decomposed and removed from the specimens. Then, in the sintering process the printed part without PLA is interested by raising its temperature to a value below melting point of copper but high enough for copper particles to bond together. In general, the time required in the entire fabrication process exceeds 24 hours, excluding the 3D printing time. Based on the developed model, this study performs a numerical simulation of the entire process in an attempt to improve the efficiency of the fabrication. The goal of present study is to develop a complete and novel numerical module for the thermal treatment process of the metallic printed parts which are necessary to understanding the physical insight of the PLA removal and sintering processes.

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