Properties of 16G2AF steel after normalizing and hardening and tempering

Conclusions

• 1. Tensile tests of unnotched specimens at normal temperature do not reveal a difference in the properties of hardened and tempered and normalized 16G2AF steel.

• 2. The toughness of 16G2AF steel after hardening and tempering is significantly higher than after normalizing. The ductile to brittle transition temperature T₅₀ drops by 50°C (from −10 to −60°C) and even in the area of ductile fracture (at 20°C) the impact strength of a specimen with a crack increases by four times.

• 3. The high toughness of hardened and tempered 16G2AF steel is the result of features of the structure of the carbide (carbonitride) phase formed in the martensitic—bainitic structure in high-temperature tempering.