True Stress–True Strain Relationship up to the Plastic Deformation Limit in Ferrite–Pearlite Steel at Various Temperatures

This study investigated the true stress (σ)–true strain (ε) relationship up to plastic deformation limit in ferrite–pearlite (FP) steel at various temperatures. We found that a decrease temperature resulted an increase lower yield strength (LYS) and tensile (TS), both uniform total elongations. When was increased from 673 773 K, TS elongations decreased due blue brittleness. In σ–ε of FP temperatures, ε with correlated reduction cross-sectional area specimen. Microcracks were observed cementite plates as well tearing pearlite lamellae. The dependence fracture (σZ) small. particular, values σZ range ductile almost same, is applicable condition limit. ratio LYS 0.5, fraction brittle 50%.