BSS 7273 — Interlaminar fracture toughness (DCB / ENF) for fiber‑reinforced composites

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BSS 7273 is a Boeing company standard used in aerospace composite testing to characterize interlaminar fracture toughness, the resistance of a laminate to delamination between plies. To match this to your program, talk with our team.

What BSS 7273 Covers

It defines interlaminar fracture toughness testing of fiber-reinforced composite laminates, using fracture-mechanics configurations to generate energy-release-rate values for material qualification and design allowables.

How the Test Is Run

A pre-cracked laminate coupon is loaded to grow a delamination between plies, most commonly the double cantilever beam (DCB) for Mode I opening and the end-notched flexure (ENF) for Mode II shear, and the critical energy release rate is calculated.

Why It Matters

Delamination resistance is a critical damage mode and design limiter for composite aerostructures; a fracture-mechanics fixture (DCB or ENF), sensitive load and displacement measurement, and crack-length tracking are essential.

Reading the Designation

Cited as BSS 7273 with its edition or revision. Confirm the current version and programme requirements before finalizing setup. To configure a testing setup, request a quote.

Related Standards

ASTM D5528 is the public Mode I (DCB) interlaminar fracture toughness method and BSS 7260 is the Boeing compression-after-impact companion.

Request a Quote

Setting up interlaminar fracture toughness testing to BSS 7273? Request a quote and our team will help you build a system matched to your laminate layup and fixture type (DCB or ENF).


TensileMill CNC products for BSS 7273

Our specimen-preparation systems and testing equipment compatible with BSS 7273:


Set up BSS 7273 testing with TensileMill CNC

TensileMill CNC designs and builds the systems labs use for standards-based mechanical testing. Depending on your specimens, that can include universal testing machines with composite grips and fixtures for tension, compression, and shear coupons. Let us know your application and our engineers will help you build a compliant BSS 7273 setup.