文章信息/Info

Title:

Advances in rolling-spinning technique of titanium tubes

作者:

郭靖1; 2; 詹梅1; 2; 楊合1; 2

1. 西北工業大學 凝固技術國家重點實驗
2. 西北工業大學 材料學院

Author(s):

GUO Jing1; 2;  ZHAN Mei1; 2;  YANG He1; 2

(1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University
2. School of Materials Science and Engineering, Northwestern Polytechnical University

關鍵詞:

鈦合金; 環軋-旋壓; 有限元; 微觀組織演化; 損傷演化

DOI:

10.7502/j.issn.1674-3962.2016.04.05

文獻標志碼:

A

摘要:

鈦合金筒形件具有輕質、高強、耐腐蝕等優點，在航空、航天和兵器領域有著廣泛的應用與需求。針對目前的鈦合金筒形件成形制造工藝難以滿足大直徑薄壁長筒形件的高效、低成本制造要求，提出了一種環軋-旋壓(軋-旋)成形工藝制造鈦合金筒形件的方法。在軋-旋成形工藝中，坯料歷經環軋線接觸與旋壓點接觸下的連續局部加載增量成形和顯著的不均勻變形，其變形過程復雜，微觀組織不均勻，容易發生破裂，影響筒形件的成形質量。為此，基于兩相鈦合金自洽模型和Oyane韌性準則，建立了耦合損傷的軋-旋宏微觀仿真模型，研究了TA15鈦合金筒形件軋-旋過程中的宏觀變形行為、微觀組織和損傷破裂演化規律。發現工件經軋-旋成形后，外層應變較大，中間層和內層基本相同；工件溫度沿壁厚由內到外逐漸降低；α晶粒尺寸外層最小，內層和中間層相差不大；α相體積分數沿壁厚由內到外逐漸降低；工件內表面在環軋后的旋壓過程中，由于正應力三軸度以及高應變速率的共同作用，最易發生破裂。

Abstract:

Due to the characteristics of light weight, high strength and good corrosion resistance, titanium tubes have been widely applied and needed in the fields of aviation, aerospace and weapon. Considering that the existing processes are difficult to manufacture long, thin-walled titanium tubes with large diameter in efficiency and at low cost, a new tube forming technique by combining ring-rolling and tube spinning (called rolling-spinning) is developed by authors. In the rolling-spinning process, blanks experience continuous local loading forming under the line contact action in ring-rolling process and point contact action in tube spinning process. These forming characteristics would lead to complex deformation history, inhomogeneous microstructure and fracture, which would finally affect the performance of tubes. Therefore, based on the two-phase self-consistent model and Oyane criterion, a macro-micro finite element model coupling the damage effects is established. Using this model, the macro deformation behaviors, microstructure and damage evolutions are investigated. The results indicate that after the rolling-spinning process, the strain and α grain size are largest in the outer zone of the workpiece, while the strain and α grain size are almost same in the inner and center zones of the workpiece; the temperature and volume fraction of α phase decrease along from the outer surface to inner surface of the workpiece; the fracture would occur in the inner surface of workpiece during the spinning process due to the coupling effects of positive stress triaxiality and high strain rate.