Charpy Specimen
A Charpy specimen is used in the Charpy impact test, which measures the amount of energy absorbed by a material during fracture. This test provides insight into the material's notch toughness and ability to absorb energy during impact.
Overview
Key Features:
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Geometry: Rectangular bar with a V-notch or U-notch machined on one side.
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Dimensions: Standard dimensions are specified by ASTM E23. Common sizes are 55 mm in length with a cross-section of 10 mm × 10 mm.
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Notch: The notch acts as a stress concentrator to promote fracture initiation.
Testing Procedure:
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Specimen Placement: Positioned horizontally on supports in the impact tester with the notch facing away from the striker.
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Impact: A pendulum hammer strikes the specimen on the face opposite the notch.
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Energy Measurement: The energy absorbed in breaking the specimen is measured, usually in joules.
Applications:
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Assessing the ductile-to-brittle transition temperature of materials.
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Evaluating the impact toughness of metals, particularly in the context of structural applications.
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Comparing the toughness of different materials or heat treatments.