Consideration of particle-strengthening mechanism of copper-precipitation-strengthened steels by atom probe tomography analysis

► APT analysis of Cu steel was performed to elucidate particle strengthening mechanism. ► Cu particle diameter dependence on interaction force per particle was obtained. ► The interaction force gradually increased after the Cu transformation of bcc to 9R. ► The difference in elastic modulus was the main strengthening mechanism. ► Balance of particle spacing, volume fraction and the force produced maximum region.