潤滑劑對固體/粉體複合擠製之影響

Abstract

在固體/粉體複合包芯材擠製中，如何使粉末具有良好的流動性一直是影響擠製成品品質的重要因素。擠製過程中粉體流動性的良好與否，不僅會影響到粉體的密度分佈，更會影響到成形後胚體的強度。 本研究的目的在於探討潤滑劑對固體/粉體複合擠製產生的效應。研究中先利用簡單的漏斗實驗，來瞭解潤滑劑對粉末流動性的影響，並找出潤滑劑的種類與混合比對粉體粒子大小分佈、流動性等之影響，最後再將此實驗結果應用於複合擠製。 由實驗的結果可以得到，無法用較簡單的漏斗實驗來模擬複合擠製實驗。在複合擠製實驗中，潤滑劑的添加與否的確會影響粉體的流動性，但是添加量不宜太多，以免造成不好的流動性，造成擠製成品的缺陷。

The aim of this research is to study the possibility of increasing the flowability of ceramic powder under extrusion . The flowability of powder during the extrusion process will not only affect the distribution of powder density after extrusion , but also the strength of product . In the experiment , we chose several different lubricants , mix these lubricant with the powder , then conduct a simple funnel experiment . The volume percent of the lubricant is taked as a parameter in the experiment . From funnel experiment results we select those combination of mixture conditions that have a faster dropping speed and then conduct the extrusion process . It is found that the lubricant can affect the flowability of the powder during extrusion , however , the quantity of the lubricant presented in the powder mixture is also critical to the extrusion process .