以ABAQUS模擬粉體之壓實行為

Modelling the compaction behaviour of powders with ABAQUS

呂紹垣(Shao-Yuan Lyu)

指導教授 ： 吳柏林 ； 田永銘

國立中央大學/工學院/土木工程學系/碩士(2006年)

摘要

目前世界各國主要以單軸壓實法壓製緩衝材料，本研究根據瑞典單軸壓實法之概念，藉以數值方法來探討粉體材料受壓實力下之力學行為，以作為未來緩衝材料之設計參考。
　　緩衝材料塊體一般可分為盤形、扇形及環形等形狀，本研究嘗試利用粉體受壓實力作用下產生之應變硬化模式（Drucker-Prager/Cap Model），建立至大型的非線性有限元素分析軟體（ABAQUS）中，利用合理的分析條件及適當的材料參數，針對三種不同形狀之緩衝材料塊體進行數值模擬，探討不同外形之緩衝材料塊體於壓實過程中之力學行為差異。
　　此外，緩衝材料塊體壓製過程中，材料與模具間會產生壁面摩擦力，單純的施加壓實應力與密度之關係並無法真正表現粉體之壓實特性，故須找出不受試驗條件影響之無壁面摩擦力壓縮曲線。本數值模擬分別以摩擦係數為零之方式及平均壓實應力法求取無壁面摩擦力壓縮曲線，並與前人所做之試驗結果加以比較，驗證數值分析模式之可行性及適用性。

關鍵字

壓實 ； 粉體 ； ABAQUS ； Drucker-Prager/Cap Model

並列摘要

Many nations take advantage of uniaxial compaction to produce buffer materials. This research aims to discuss the mechanical behavior of powders in compaction with numerical method.
　　The buffer material blocks usually have three shapes, inculding disk, fan, and ring. With rational consideration and appropriate material parameters in finite elements analysis（ABAQUS）, this research attempts to distinguish the diversity among these buffer material blocks. Drucker-Prager/Cap Model was chosen as the yield surface of the medium, which represents the failure and yield behaviors.
　　In addition, as the buffer material blocks in the process of compaction, it will produce wall friction between the block and the die. The relationship between compaction stress and density cannot reveal the characteristics of the powders in compaction. It’s necessary to find out the friction-free curve that without limited in the experimental conditions. This research use zero as the coefficient of friction and average integral method to get friction-free curve, and make these results to compare with the former researches in order to verify the feasibility of numerical analysis.

並列關鍵字

powder ； ABAQUS ； Drucker-Prager/Cap Model ； compaction

參考文獻

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