Wall Thinning Characteristics of Ti-3Al-2.5V Tube in Numerical Control Bending Process

doi:10.1007/s12204-019-2079-1

Abstract

Abstract: A finite element (FE) model for the numerical control (NC) bending of Ti-3Al-2.5V titanium alloy seamless tube is established, considering the variation in the contractile strain ratio (CSR) and elastic modulus (E). The wall thinning characteristics of Ti-3Al-2.5V tube under different geometric and process conditions were investigated. The results showed that the CSR-E variation can change the wall thickness, but has no remarkable effect on the change characteristics. The reasonable parameter ranges are as follows: a bending-radius range not less than 1.5 times the outer diameter, a bend angle up to 180?, and a mandrel extension of 0—3mm. The friction coefficient between the pressure die and the tube should be in the range of 0.20—0.35, and between the bending die and the tube should be in the range of 0.05—0.15. As long as the performance meets the requirements, the relative push-assistant speed should be as small as possible.

Key words: titanium alloy tube| numerical control bending| wall thinning| contractile strain ratio| elastic modulus

摘要： A finite element (FE) model for the numerical control (NC) bending of Ti-3Al-2.5V titanium alloy seamless tube is established, considering the variation in the contractile strain ratio (CSR) and elastic modulus (E). The wall thinning characteristics of Ti-3Al-2.5V tube under different geometric and process conditions were investigated. The results showed that the CSR-E variation can change the wall thickness, but has no remarkable effect on the change characteristics. The reasonable parameter ranges are as follows: a bending-radius range not less than 1.5 times the outer diameter, a bend angle up to 180?, and a mandrel extension of 0—3mm. The friction coefficient between the pressure die and the tube should be in the range of 0.20—0.35, and between the bending die and the tube should be in the range of 0.05—0.15. As long as the performance meets the requirements, the relative push-assistant speed should be as small as possible.

关键词: titanium alloy tube| numerical control bending| wall thinning| contractile strain ratio| elastic modulus

CLC Number:

TG 386.3

HUANG Tao (皇涛), WANG Kun (王锟), ZHAN Mei (詹梅), GUO Junqing (郭俊卿), CHEN Xuewen (陈学文), CHEN Fuxiao (陈拂晓), SONG Kexing (宋克兴). Wall Thinning Characteristics of Ti-3Al-2.5V Tube in Numerical Control Bending Process[J]. Journal of Shanghai Jiao Tong University (Science), 2019, 24(5): 647-653.

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