Drilling induced exit-ply delamination model considering torque

Ramesh, S and Kubher, S and Gururaja, S (2020) Drilling induced exit-ply delamination model considering torque. In: 18th European Conference on Composite Materials, ECCM 2018, 24-28 June 2018, (MAICC)Athens; Greece.

PDF ECCM_2018.pdf - Published Version Restricted to Registered users only Download (429kB)

Abstract

Amongst all the drilling induced damage in laminated multi-directional fiber reinforced plastics (MD FRPs), exit-ply delamination is the most serious one. Exit-ply delamination is mainly caused due to the axial thrust force exerted by the chisel edge of the drill. Several attempts have been made in the past to provide analytical models relating material properties, layups, machining parameters (feed) with the delamination on the exit-side of the drilled hole. In the current work, a modified exit-ply delamination model has been presented using first order shear deformation theory (FSDT) in conjunction with classical lamination plate theory (CLPT) to account for the out-of-plane shear stresses txz and tyz that are generated due to the rotation of the drill bit. The delamination zone is assumed to be an elliptical plate that is clamped on all edges and subjected to thrust force and torque along the axis of the drill. Suitable displacements fields have been assumed and a mixed-mode fracture criterion has been used to estimate the critical thrust force. These results have been verified experimentally. These forces can further be related to the process variables, viz., feed rate and cutting speed.

Item Type:	Conference Paper
Publication:	ECCM 2018 - 18th European Conference on Composite Materials
Publisher:	Applied Mechanics Laboratory
Additional Information:	Copyright of this article belongs to Applied Mechanics Laboratory
Keywords:	Drilling torque; Exit ply delamination; LEFM; MD-FRP laminates
Department/Centre:	Division of Mechanical Sciences > Aerospace Engineering(Formerly Aeronautical Engineering)
Date Deposited:	27 Feb 2020 09:37
Last Modified:	08 Dec 2022 06:22
URI:	https://eprints.iisc.ac.in/id/eprint/64360

Actions (login required)

View Item