Temperature range where ferritic steels shift from high absorbed impact energy (ductile) to low energy (brittle) fracture; mapped with Charpy or Izod energy versus test temperature.
Temperature range where ferritic steels shift from high absorbed impact energy (ductile) to low energy (brittle) fracture; mapped with Charpy or Izod energy versus test temperature.
The ductile-to-brittle transition (DBTT) curve shows how impact absorbed energy changes with test temperature. Ferritic steels often exhibit an upper shelf (ductile), a transition region, and a lower shelf (brittle).
Notched bars are broken in a pendulum impact tester at multiple temperatures (often after conditioning in a thermal chamber). Energy versus temperature is plotted; project specs may define acceptance at a reference temperature or require 50% shelf energy criteria.
ISO 148-1 and ASTM E23 govern specimen geometry, striker, and energy calculation. Report notch type, specimen size (KV2, etc.), and thermal soak time because transition position shifts with microstructure and strain rate.
Insufficient temperature control, misaligned specimens, and comparing energies from different notch sizes or sub-size bars without standard conversion rules.
Charpy impact test systems and Charpy testing machines for metals — absorbed energy, notch toughness, ISO 148-1 and ASTM E23. Vector designs manual, semi-automatic, and robotic Charpy lines from 300 J to 750 J, including sub-zero Charpy, tailored to your laboratory.
Series: Charpy
Izod impact test systems and Izod testing machines for plastics, polymers, and metals — cantilever notch-bar absorbed energy per ISO 180, ASTM D256, and ASTM E23 Izod methods. Vector configures pendulum impact testers from 5.5 J to 50 J (and higher-energy metals options) to your laboratory.
Series: Izod
Normalize Charpy or Izod absorbed energy to impact toughness aK using ligament area beneath the notch.
Open calculator →Charpy Impact Test
A notched bar is broken by a swinging pendulum striker; absorbed energy KV or KU (joules) characterizes toughness and ductile-to-brittle transition versus temperature.
Izod Impact Test
A notched cantilever specimen is struck on its notched face by a pendulum; absorbed energy reflects toughness with a different stress distribution than Charpy.
Absorbed Impact Energy
Kinetic energy lost by the pendulum striker when a notched specimen fractures, reported in joules after friction corrections per Charpy or Izod methods.
