Charpy Impact Test
Purpose: To determine the impact toughness of materials over a temperature range from –196 °C to 500 °C using Charpy V-notch (CVN) and Charpy U-notch (CUN) methods in accordance with EN and ASTM standards. Testing is performed on two calibrated impact machines, ensuring accurate and reliable results
The V-notch test is primarily used to evaluate fracture toughness and ductile-to-brittle transition behavior under severe stress concentration, while the U-notch method is applied where specified by certain material standards or project requirements.
Cryogenic testing down to –196 °C is essential for LNG, offshore, and low-temperature service applications to prevent brittle failure, whereas high-temperature impact testing up to 500 °C supports material qualification for power generation, refinery, and other high-temperature industrial components.
Lateral expansion (LE) of Charpy V-notch specimens is determined following impact fracture as a quantitative measure of plastic deformation capacity at the notch root and an indirect indicator of fracture mode (ductile versus brittle behavior). The measurement is performed using a dedicated lateral expansion gauge in accordance with ASTM E23 .
Standards: ASTM A370, ASTM E23, EN 875, ISO 148-1, ISO 9016