若干關(guān)鍵技術(shù)
(上海交通大學(xué) 模具CAD國家工程研究中心，
上海 200030)
摘 要: 推導(dǎo)了采用六面體等參單元網(wǎng)格劃分的金屬三維擠壓成形過程數(shù)值模擬中的摩擦力功率泛函在局部坐標(biāo)系的一階和二階偏導(dǎo)數(shù)的表達式， 提出了有效的三維六面體網(wǎng)格劃分和網(wǎng)格質(zhì)量控制技術(shù)處理方法。 以此為基礎(chǔ)， 建立了三維剛塑性有限元數(shù)值模擬系統(tǒng)和六面體網(wǎng)格再劃分系統(tǒng)。 方坯料反向擠壓過程數(shù)值模擬的結(jié)果與實驗非常吻合， 驗證了所推導(dǎo)的公式和開發(fā)的系統(tǒng)； 圓坯料側(cè)向擠壓過程的模擬驗證了提出的網(wǎng)格質(zhì)量控制技術(shù)的第三種方法。
關(guān)鍵字: 擠壓工藝； 數(shù)值模擬； 三維剛塑性有限元法
（National Die & Mould CAD Engineering Research Center, Shanghai Jiaotong University,Shanghai 200030, China）
Abstract:The derivatives of the first order and the second order of the calculus of the function of the frictional power induced by the boundary friction force were deduced, which will be the foundation in simulating 3-D extrusion processes. In addition, the effective methods for initial meshing and mesh quality control were presented. The self-developed simulation system and remeshing system coupled with the commercial system DEFORM3D were used to simulate several extrusion processes, and the simulation results fit well with the experimental results, which verified the reliability of the proposed methods.
Key words: extrusion; numerical simulation; 3-D rigid-plastic finite element formulations
