D5045-14 – Standard Test Method Technical Guide

ASTM D5045-14 (Reapproved 2022) provides a standardized methodology for characterizing the fracture toughness of plastic materials. The test methods are designed to determine the critical-stress-intensity factor ($K_{Ic}$) and the critical strain energy release rate ($G_{Ic}$), representing the resistance to fracture at crack initiation under a plane-strain condition. These parameters are essential for engineering design and material selection for load-bearing plastic components.

📐 Specimen Geometries and Types

The standard covers two primary testing geometries to evaluate fracture toughness: the single-edge-notch bending (SENB) and the compact tension (CT). Dedicated annexes in the standard provide the specific requirements for testing each geometry, including details on specimen preparation, dimensions, and loading fixtures.

• Single-Edge-Notch Bending (SENB): A center-notched beam loaded in three-point bending.
• Compact Tension (CT): A single-edge notched plate loaded in tension.