由於人類社會的蓬勃發展，致使地球的天然資源如：石油、礦產，漸漸消耗殆盡，如何解決資源短缺是現今各國政府棘手的問題。若能從廢料中取得原料並回收再利用，即可減緩自然資源消耗速率。台灣的天然資源匱乏，目前已無自產銅礦可供提煉。過去含銅產品分為兩大類，即電線電纜和銅合金產品，而電線電纜消耗佔全球精煉銅產量約三分之二。本研究以循環經濟的概念，將廢棄的銅電纜經由氣霧法將其熔煉產出球狀銅粉，再藉由自行開發的粉末扁平化裝置把球狀銅粉碾壓成片狀，最後應用於積層陶瓷電容上。
本研究使用氣霧法製程之4N純銅粉末，以輥軋式扁平化裝置進行參數的研究，過程中探討振動進料機的粉末進料率、輥輪轉速及輥輪線壓力等製程參數對於片狀銅粉特性之影響，並比較乾式及濕式輥軋兩種作法對於微結構及扁平比率之差異，最後找出最佳的製程參數。
研究結果顯示，乾式輥軋法在進料率48.8 g/min、輥軋轉速10 rpm及線壓力70 N/mm的操作參數下，經過重覆四次的輥軋後，可獲得最佳的扁平比率53.23%。而濕式輥軋的作法與乾式輥軋法作法相同，乙醇滴定流量為19.73 g/min，以避免銅粉在輥軋的過程中冷焊於輪面上。濕式輥軋法在各輥輪轉速下使用線壓力130 N/mm下進行輥軋，扁平比率約在23%左右，雖然扁平比率的表現不及乾式作法，但其微結構緻密度相當高是非常適合應用於積層陶瓷電容上，且濕式輥軋製程相較於傳統球磨可大幅減少時間及成本。

Due to the quick development of human society, it causes the earth’s natural resources such as oil and minerals are almost been consumed. If we can obtain the useful substance by recycling waste, then the natural resource consumption rate can be reduced. Nowadays, natural resources in Taiwan are not enough to produce copper mines for refining. In the past, products made of copper are classified into following two categories: electric wires and copper alloy products. It is estimated that two-thirds of the refined copper was used to produce electric wires. This study will follow the concept of circular economy, the wasted electric cable is melted by gas atomization to produce spherical copper powder, then which is rolled into flattened morphology by the self-developed flattening device. Finally, the flattened powder applied to the multilayer ceramic capacitor. In this study, we use pure copper (purity 99.99%) as the experimental material to study the parameters of the roll flattening device, the effects of parameters such as powder feed rate, roller speed, roller line pressure on the characteristics of flake copper powder are discussed. The optimization parameter is based on the microstructure of flake copper powder and flattening ratio. Results show that the flattening ratio is 53.23%.,as the powder feeding rate is 48.8 g/min, roller speed is 10 rpm and the roller line pressure is 70 N/mm after four times rolling without adding any coolant like Ethanol. To prevent the copper powder from being cold welded to the roller surface during the rolling process, we conducted the experiment by adding ethyl alcohol on the roller at the same time when the roller line pressure is 130 N/mm, the flattening ratio is decreased to 23%.Althought the flattening performance is not better than the method without adding the coolant, the micrograph of the flake copper powder by the scanning electron microscopy shows the fine microstructure in the surface morphology, which is useful to produce the multilayer ceramic capacitor. Consequently, the rolling process can be used to reduce time and cost compared to the conventional ball milling.

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