EN 2377:1989

Overview

EN 2377:1989 - Aerospace series - specifies a laboratory test method for determining the apparent interlaminar shear strength of textile glass fibre reinforced plastics (GFRP) produced in sheet form for aerospace use. The standard defines a controlled delamination-based test to quantify the shear performance between plies (interlaminar region) of textile glass‑fibre composite sheets intended for aircraft and aerospace structures.

Key topics and requirements

The standard covers the essential elements needed to perform and report a reproducible interlaminar shear test without prescribing numerical parameters in this summary. Main technical topics typically included are:

• Scope and applicability - materials (textile GFRP in sheet form) and intended aerospace use.
• Specimen preparation - how to select and prepare representative test specimens from production sheets, including orientation and cutting.
• Pre‑conditioning and test environment - requirements for conditioning specimens and controlling laboratory environmental conditions to ensure comparable results.
• Test apparatus and setup - description of the mechanical test arrangement used to initiate and propagate a controlled delamination (shear loading by a prescribed fixture).
• Test procedure - stepwise method for applying load, monitoring delamination, and recording load/displacement data.
• Calculation and interpretation - how to derive the apparent interlaminar shear strength from measured data and report it as a material property.
• Reporting - required documentation of test conditions, specimen details, results and any deviations from the method.

Applications and users

EN 2377:1989 is practical for organizations involved in aerospace composite materials where interlaminar shear is a critical performance parameter:

• Composite material manufacturers (quality control and incoming inspection)
• Aerospace OEMs and tier suppliers (material specification and procurement)
• Test laboratories (type testing and verification)
• Materials and structural engineers (design validation and failure analysis)
• R&D groups developing textile glass fibre laminates and processing methods

Measuring apparent interlaminar shear strength supports decision-making about laminate stacking, adhesive bonding, damage tolerance and processing controls in aerospace component manufacture.

Related standards

This standard is part of aerospace series testing for composites. Users commonly consult EN 2377 alongside other EN/ISO composite test methods for tensile, compressive, flexural and interlaminar properties, and with aerospace material qualification requirements to build a complete mechanical property dataset.

Keywords: EN 2377:1989, interlaminar shear strength, glass fibre reinforced plastics, aerospace composites, test method, delamination test, textile glass fibre, sheet laminates.