Deformation response of 1200 MPa grade martensite-ferrite dual-phase steel under high strain rates

Deformation response of DP1200 steel was studied under high strain rate. Ferrite cracking occurs when strain rate exceeds the critical range (500-700 s(-1)). Cracks in ferrite propagate to martensite/ferrite interface, weakening its inhibitory effect on adjacent martensite. Thus martensitic deformation becomes the main factor of total deformation earlier to enhance the total strength.