(1. 重慶理工大學(xué) 材料科學(xué)與工程學(xué)院，重慶 400050；
2. 重慶大學(xué) 材料科學(xué)與工程學(xué)院，重慶 400044；
3. 重慶科技學(xué)院 冶金與材料學(xué)院，重慶 401331；
4. 陸軍勤務(wù)學(xué)院 化學(xué)與材料學(xué)院，重慶 401311)
摘 要: 為了促進(jìn)鎂合金大塑性變形技術(shù)的工業(yè)化，研究了一種正擠壓與等通道擠壓相結(jié)合的鎂合金薄壁管材(Tube)擠壓(Extrusion)-剪切(Shearing)-彎曲(Bending)(簡(jiǎn)寫(xiě)為T(mén)ESB)連續(xù)塑性成形方法；采用有限元法對(duì)TESB變形過(guò)程進(jìn)行計(jì)算機(jī)數(shù)值模擬。在擠壓機(jī)上安裝TESB成形模具，進(jìn)行擠壓成形試驗(yàn)，對(duì)擠出的管材進(jìn)行微觀組織觀察及硬度測(cè)定，并對(duì)數(shù)據(jù)進(jìn)行處理。結(jié)果表明：隨著擠壓速度的增大，管坯溫度升高明顯；隨著預(yù)熱溫度升高及摩擦因數(shù)減小，擠壓載荷會(huì)減小。TESB成形可以細(xì)化鎂合金晶粒，提高TESB成形的均勻性；隨著溫度升高，鎂合金管材硬度有所降低，但是與普通擠壓相比，鎂合金管材硬度明顯上升，硬度最大值出現(xiàn)在剪切區(qū)和彎曲區(qū)交界位置。TESB成形是一種新型的鎂合金管材大塑性變形方法，可以有效地細(xì)化晶粒、提高組織的均勻性。
關(guān)鍵字: 鎂合金薄壁管材；大塑性變形；數(shù)值模擬；微觀組織
（1. School of Materials Science and Engineering, Chongqing University of Technology, Chongqing 400050, China;
2. School of Materials Science and Engineering, Chongqing University, Chongqing 400044, China;
3. School of Metallurgy and Materials, Chongqing University of Science and Technology, Chongqing 401331, China;
4. School of Chemistry and Materials, Army Service College, Chongqing 401311, China）
Abstract:In order to promote the industrialization of large plastic deformation technology of magnesium alloy, an tube extrusion-shearing-bending (TESB) forming method of magnesium alloy thin-walled tube was studied by combining forward extrusion and equal channel angle extrusion. The deformation process of TESB was simulated by finite element method. The TESB forming die was installed on the extruder and TESB experiments have been done. In order to observe the microstructures of the extruded tube, the testing data were processed. The results show that the preheated temperature of tube increase with the rise of extrusion speeds obviously, and the extrusion loads decrease with the rise of preheated temperatures and the dropping of friction factors. TESB forming can refine the microstructures of magnesium alloy tube and improve the forming efficiency. TESB is a new method of large plastic deformation of magnesium alloy tube, which can effectively refine the grains and improve the uniformity of microstructures.
Key words: magnesium alloy thin-walled tube; large plastic deformation; numerical simulation; microstructure
