(1. 河南科技大學(xué) 材料科學(xué)與工程學(xué)院，洛陽(yáng) 71023；
2. 洛陽(yáng)理工學(xué)院 材料科學(xué)與工程學(xué)院，洛陽(yáng) 71023)
摘 要: 通過(guò)有限元分析和實(shí)驗(yàn)研究動(dòng)態(tài)流量控制法擠壓鈦合金彎管件。實(shí)驗(yàn)驗(yàn)證彎管的尺寸精度和擠壓載荷。分析調(diào)控量對(duì)彎曲曲率的影響、速度場(chǎng)和溫度場(chǎng)。結(jié)果表明：擠壓載荷的峰值誤差為14.51%，擠出的管材彎曲曲率誤差為3.47%；在模具結(jié)構(gòu)中，調(diào)控通道Ⅱ截面面積不變時(shí)，彎管曲率半徑隨調(diào)控通道Ⅰ有效截面面積的增大而增大；在定徑帶處的合金呈非均勻流動(dòng)，彎管件內(nèi)外弧面存在流速差是擠出彎曲件的原因；合金的流速在通過(guò)定徑帶時(shí)發(fā)生分流補(bǔ)償，由調(diào)控通道Ⅱ進(jìn)入定徑帶的合金流速反超輔助通道內(nèi)的流速，在焊合腔內(nèi)邊緣處存在金屬流動(dòng)死區(qū)。在定徑帶區(qū)域溫升明顯，最大溫升為134 ℃。
關(guān)鍵字: 彎管；擠壓；動(dòng)態(tài)流量調(diào)控；鈦合金
（1. School of Material Science and Engineering, Henan University of Science and Technology, Luoyang 471023, China;
2. School of Material Science & Engineering, Luoyang Institute of Science and Technology, Luoyang 471023, China）
Abstract:The dynamic flow control extrusion (DFCE) of titanium alloy bending tubes was examined in the present study using both the finite element analysis and the experimental approach. The finite element analysis was first validated qualitatively and quantitatively by the experimental data obtained from the DFCE process. The effects of the area of channel cross section on the radius of curvature were studied by the finite element analysis. The fields of velocity and temperature of workpiece were studied. The results show that the relative errors of extrusion load and radius of curvature are 14.51% and 3.47%, respectively. The finite element analysis reveals that radius of curvature increases with the increase of cross-sectional area of controlling channel-Ⅰ. The different cross-sectional area of controlling channel-Ⅰand Ⅱ is found to be one major reason for the extrusion of bending tube. The velocity of workpiece is inhomogeneous in circumferential of bearing zone. The velocity of alloy flowing through die bearing from controlling channel-Ⅱ increases rapidly than that from auxiliary channel. The temperature rise is obviously and the maximum value is 134℃.
Key words: bending tube; extrusion; dynamic flow control extrusion; titanium alloy
