Multi-margin drill structure for improving hole quality and dimensional consistency in drilling Ti/CFRP stacks

Zhen yuan Jia, Chong Zhang, Fu ji Wang, Rao Fu, Chen Chen

Research output: Contribution to journalArticle

Abstract

Low damage and accurate dimension are crucial requirements in the drilling of aerospace structures, especially for bearing components of Ti/CFRP stacks. However, tremendous differences in material properties between Ti and CFRP have brought significant challenges to the drilling quality/accuracy control. This paper presents a novel cutting depth control drill structure for improving drilling quality/accuracy of Ti/CFRP stack. Considering the different elastic modulus of two materials, a two-dimensional cutting model was applied to analysis the cutting process of Ti, CFRP, Ti/CFRP interface and CFRP exit. Then, the effects of the cutting depth on the spring-back of the machined surface and the delamination of the outlet are clarified, and the small cutting depth is suggested to be adopted. A multi-margin structure is proposed on second-step of the step drill bit in order to perform the cutting depth control strategy, and the geometrical analyses reveal that the multi-margin structure could effectively reduce the cutting depth in drilling Ti/CFRP stack. Finally, comparative experimental verifications are carried out, and the multi-margin structure is proved to be effective in reducing drill-exit damages of CFRP and controlling hole diameter deviations for both Ti and CFRP within the tolerance.

LanguageEnglish
Article number116405
JournalJournal of Materials Processing Technology
Volume276
DOIs
Publication statusPublished - 01 Feb 2020

Fingerprint

Carbon fiber reinforced plastics
Drilling
Bearings (structural)
carbon fiber reinforced plastic
Delamination
Quality control
Materials properties
Elastic moduli

Keywords

  • Cutting depth
  • Drill structure
  • Drilling
  • Hole diameter
  • Ti/CFRP stack

Cite this

@article{a216de1d8fde47e5acc69738363de807,
title = "Multi-margin drill structure for improving hole quality and dimensional consistency in drilling Ti/CFRP stacks",
abstract = "Low damage and accurate dimension are crucial requirements in the drilling of aerospace structures, especially for bearing components of Ti/CFRP stacks. However, tremendous differences in material properties between Ti and CFRP have brought significant challenges to the drilling quality/accuracy control. This paper presents a novel cutting depth control drill structure for improving drilling quality/accuracy of Ti/CFRP stack. Considering the different elastic modulus of two materials, a two-dimensional cutting model was applied to analysis the cutting process of Ti, CFRP, Ti/CFRP interface and CFRP exit. Then, the effects of the cutting depth on the spring-back of the machined surface and the delamination of the outlet are clarified, and the small cutting depth is suggested to be adopted. A multi-margin structure is proposed on second-step of the step drill bit in order to perform the cutting depth control strategy, and the geometrical analyses reveal that the multi-margin structure could effectively reduce the cutting depth in drilling Ti/CFRP stack. Finally, comparative experimental verifications are carried out, and the multi-margin structure is proved to be effective in reducing drill-exit damages of CFRP and controlling hole diameter deviations for both Ti and CFRP within the tolerance.",
keywords = "Cutting depth, Drill structure, Drilling, Hole diameter, Ti/CFRP stack",
author = "Jia, {Zhen yuan} and Chong Zhang and Wang, {Fu ji} and Rao Fu and Chen Chen",
year = "2020",
month = "2",
day = "1",
doi = "10.1016/j.jmatprotec.2019.116405",
language = "English",
volume = "276",
journal = "Journal of Materials Processing Technology",
issn = "0924-0136",
publisher = "Elsevier BV",

}

Multi-margin drill structure for improving hole quality and dimensional consistency in drilling Ti/CFRP stacks. / Jia, Zhen yuan; Zhang, Chong; Wang, Fu ji; Fu, Rao; Chen, Chen.

In: Journal of Materials Processing Technology, Vol. 276, 116405, 01.02.2020.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Multi-margin drill structure for improving hole quality and dimensional consistency in drilling Ti/CFRP stacks

AU - Jia, Zhen yuan

AU - Zhang, Chong

AU - Wang, Fu ji

AU - Fu, Rao

AU - Chen, Chen

PY - 2020/2/1

Y1 - 2020/2/1

N2 - Low damage and accurate dimension are crucial requirements in the drilling of aerospace structures, especially for bearing components of Ti/CFRP stacks. However, tremendous differences in material properties between Ti and CFRP have brought significant challenges to the drilling quality/accuracy control. This paper presents a novel cutting depth control drill structure for improving drilling quality/accuracy of Ti/CFRP stack. Considering the different elastic modulus of two materials, a two-dimensional cutting model was applied to analysis the cutting process of Ti, CFRP, Ti/CFRP interface and CFRP exit. Then, the effects of the cutting depth on the spring-back of the machined surface and the delamination of the outlet are clarified, and the small cutting depth is suggested to be adopted. A multi-margin structure is proposed on second-step of the step drill bit in order to perform the cutting depth control strategy, and the geometrical analyses reveal that the multi-margin structure could effectively reduce the cutting depth in drilling Ti/CFRP stack. Finally, comparative experimental verifications are carried out, and the multi-margin structure is proved to be effective in reducing drill-exit damages of CFRP and controlling hole diameter deviations for both Ti and CFRP within the tolerance.

AB - Low damage and accurate dimension are crucial requirements in the drilling of aerospace structures, especially for bearing components of Ti/CFRP stacks. However, tremendous differences in material properties between Ti and CFRP have brought significant challenges to the drilling quality/accuracy control. This paper presents a novel cutting depth control drill structure for improving drilling quality/accuracy of Ti/CFRP stack. Considering the different elastic modulus of two materials, a two-dimensional cutting model was applied to analysis the cutting process of Ti, CFRP, Ti/CFRP interface and CFRP exit. Then, the effects of the cutting depth on the spring-back of the machined surface and the delamination of the outlet are clarified, and the small cutting depth is suggested to be adopted. A multi-margin structure is proposed on second-step of the step drill bit in order to perform the cutting depth control strategy, and the geometrical analyses reveal that the multi-margin structure could effectively reduce the cutting depth in drilling Ti/CFRP stack. Finally, comparative experimental verifications are carried out, and the multi-margin structure is proved to be effective in reducing drill-exit damages of CFRP and controlling hole diameter deviations for both Ti and CFRP within the tolerance.

KW - Cutting depth

KW - Drill structure

KW - Drilling

KW - Hole diameter

KW - Ti/CFRP stack

UR - http://www.scopus.com/inward/record.url?scp=85072542058&partnerID=8YFLogxK

U2 - 10.1016/j.jmatprotec.2019.116405

DO - 10.1016/j.jmatprotec.2019.116405

M3 - Article

VL - 276

JO - Journal of Materials Processing Technology

T2 - Journal of Materials Processing Technology

JF - Journal of Materials Processing Technology

SN - 0924-0136

M1 - 116405

ER -