文章信息/Info

Title:

Research on the Forming Limit of Copper-Titanium Bimetallic Composite Tube with Small Radius of Rotary-Draw Bending Based on Wrinkling

文章編號:

1674-3962(2023)03-0266-06

作者:

萬苗苗; 朱英霞; 陳蓉; 涂文斌

（江蘇大學機械工程學院，江蘇 鎮江 212013）

Author(s):

WAN Miaomiao;  ZHU Yingxia;  CHEN Rong;  TU Wenbin

(School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China)

關鍵詞:

雙金屬復合管; 繞彎成形; 起皺; 成形極限; 有限元分析

Keywords:

bimetallic composite tube;  rotary-draw bending;  wrinkling;  forming limit;  finite element analysis

分類號:

TG306

DOI:

10.7502/j.issn.1674-3962.202106018

文獻標志碼:

A

摘要:

為了得到成形質量優良、小相對彎曲半徑（R/D2≤2，D2是覆管外徑）的銅鈦雙金屬復合管，基于ABAQUS/Explicit有限元平臺，建立了銅鈦雙金屬復合管繞彎�不貜椨邢拊�模型，對銅鈦雙金屬復合管小半徑繞彎成形的起皺極限進行有限元模擬和分析。即在剛性芯模、不同芯頭個數填充下，得到防止復合管起皺發生的最小相對彎曲半徑（R/D2）min。結果表明，基、覆管填充區的截面畸變率（φ）均明顯小于非填充區，且填充區的φ隨R/D2 減小略有增大，非填充區的φ隨R/D2減小而明顯增大，這表明非填充區的截面起皺趨勢明顯高于填充區；R/D2=1.76為起皺發生的分界線，當R/D2=1.76時，1個芯頭填充不滿足復合管成形質量的要求；2個和3個芯頭填充滿足成形質量要求，且2個芯頭填充效果較3個芯頭好；當R/D2=1.32時，3種填充條件都會出現起皺，不滿足成形質量要求。為了確定最小相對彎曲半徑，進一步分析了2個芯頭填充、R/D2=1.71和R/D2=1.74時復合管的起皺情況，發現起皺個數N=1，φmax均超過5%，不滿足成形精度要求。綜上，銅鈦雙金屬復合管的成形極限為2個芯頭填充、(R/D2)min=1.76。

Abstract:

In order to obtain the copper-titanium bimetallic composite tube with excellent forming quality and small relative bending radius (R/D2≤2, D2 is the outer diameter of the covered tube), a finite element model for bending-springback process of copper-titanium bimetallic composite tube is established based on the ABAQUS/Explicit finite element platform in this paper, and the wrinkling limit of the copper-titanium bimetallic composite tube with small radius bending is simulated and analyzed by finite element method. That is, with a rigid mandrel and different numbers of mandrel cores filling, the minimum relative bending radius (R/D2)min to prevent wrinkling is obtained. The results show that, the cross-section deformation rates φ in both the base tube and covered tube filling zones are significantly smaller than those in the non-filling zone. The φ in the filling zone slightly increased with the decrease of R/D2, while the φ in the non-filling zone significantly increased with the decrease of R/D2. This indicates that the tendency for wrinkling in the cross-section of the non-filling zone is significantly higher than that in the filling zone. R/D2=1.76 is the turning point for wrinkling occurrence. When R/D2=1.76, one core filling does not meet the forming quality requirements. When two and three cores are filled, it meets the requirements of forming quality, and the filling with two cores is better than three cores. When R/D2=1.32, wrinkles will appear under the three filling conditions, which does not meet the forming quality requirements. To determine the minimum relative bending radius, further analysis was carried out on the wrinkling of the composite pipe with two mandrel cores filling and R/D2=1.71, R/D2=1.74. It is found that number of wrinkles N=1 and φmax exceeded 5%, which does not meet the forming quality requirement. Therefore, the forming limit of the copper-titanium bimetallic composite tube is two mandrel cores filled and (R/D2)min=1.76.