The effects of aging treatment on microstructure and properties of Fe-30.0Mn-9.6Al-1.0C low-density steel were studied by OM,SEM,XRD,EBSD,and TEM.The strain hardening behavior and strengthening plasticizing mechanism were also analyzed.The results show that after aging at different temperatures,the microstructure of Fe-30.0Mn-9.6Al-1.0C low-density steel remains mostly full austenite with κ-carbide precipitates.As the aging temperature increases,the increase in κ-carbide precipitation has an enhancing effect on the strength of the low-density steel,but it will deteriorate its plasticity.After solid solution at 1050℃and aging at 450℃,the tensile strength of the low-density steel is 811 MPa,the elongation is 106.9%,and the product of strength and plasticity is 86.7 GPa·%.When aging at 500℃,the tensile strength of the low-density steel is 861 MPa,the elongation is 33.2%,and the product of strength and plasticity is 28.6 GPa·%.After solid solution at 1050℃and aging tensile deformation at different temperatures,the strain hardening index of the low-density steel exhibits a double n-value phenomenon,and the strain hardening behavior shows a multi-stage variation pattern.After tensile deformation of the low-density steel,a large number of dislocation walls,Taylor lattice and microband structures,and fine κ-carbides together enhance the strength and plasticity of the low-density steel.
维普
万方数据