Demir, B.2024-09-292024-09-2920071024-1809https://hdl.handle.net/20.500.14619/10003In this study, production of dual-phase steel from AISI 4140 steel having 0.44% C, 0.35% Si, 0.71% Mn, 1.13% Cr, 0.17% Mo and its impact strength at different martensite volume fractions (MVF) are determined. Dual-phase steel production is accomplished by intercritically annealing at intercritical temperatures (? + ? region, between 740°C and 795°C) and then by water quenching. By doing so, change in the MVF with intercritical annealing temperature (ICAT) of AISI 4140 steel is controlled. 743°C and 748°C are decided as ICAT for producing dual-phase steel impact test specimens with different MVF. For comparison, impact tests are also carried out on as-received, quenched, quenched-tempered and normalized specimens. Results show that dual-phase steel having min MVF manifests considerable higher impact energy than all the specimens except for that of the samples quenched-tempered. As a result, dual-phase microstructure produced from AISI 4140 increased the toughness significantly.eninfo:eu-repo/semantics/closedAccessAISI 4140Dual-phase steelsImpact strengthArticle2-s2.0-3904917023911669Q3115929