the development of nano/ultrafine bainitic structure in aisi 52100 steel was the goal of this study. for this purpose,the aisi 52100 the specimens were austenitized at 1050 °c for 60 min followed by low-temperature austemperingtreatment at different temperatures and times. the austempered samples were characterized using field emissionscanning electron microscopy (fesem), x-ray diffraction (xrd...

Abstract A combination of physical simulation and laboratory rolling experiments, including thermomechanical low-temperature ausforming, was conducted for designing a suitable processing route to enable phase transformation from austenite ultrafine bainite in medium-carbon steel. Following ausforming at 500-550 °C, two different cooling holding paths were tried the study: (1) water close marten...

Coalesced bainite is a coarse constituent recently found to develop along with the classical martensite, lower and upper bainite in steel weld metals. Its crystallography has been characterised using electron backscattering diffraction in combination with field emission gun scanning electron microscopy. It is confirmed that coalesced bainite grains are crystallographically homogeneous but do co...

Two experimental high strength steel weld metals were produced with 7 wt-% nickel and either 2 or 0.5 wt-% manganese. Neural network predictions that it is advantageous to reduce the manganese concentration in high nickel alloys have been confirmed, with impact energy increasing from 32 to 113 J at –40uC. High resolution microstructural investigations showed that both weld metals contained main...

There has long existed a controversy regarding the formation of the bainite phase in steels. Nonetheless, following the clear identification of bainite in 1930, several characteristic features associated with the bainite transformation became well established. These features include: the classification into upper and lower bainite; the existence of a bainite-start temperature; and the incomplet...

Two experimental high strength steel weld metals were produced with 7 wt. % nickel and manganese at 2 or 0.5 wt. %. Neural network predictions that Mn reductions increase toughness were confirmed with impact energy increasing from 32 to 113 J at –40 °C. High resolution microstructural investigations showed that both weld metals contained mainly martensite at interdendritic regions and predomina...

The development of nano/ultrafine bainitic structure in AISI 52100 steel was the goal of this study. For this purpose,the AISI 52100 the specimens were austenitized at 1050 °C for 60 min followed by low-temperature austemperingtreatment at different temperatures and times. The austempered samples were characterized using field emissionscanning electron microscopy (FESEM), X-ra...

The microstructure and microhardness of X70 pipeline steel were investigated after conducting different processing routes. was characterized using optical electron microscopy. Scanning microscopy equipped with backscattered diffraction (EBSD) transmission techniques applied for investigation thermal treatment conditions. Mechanical properties by a tester. results show that the mainly consists g...

In the current research, a complex microstructure and crystallographic data were developed through quenching partitioning (Q&P) process to improve tensile properties of commercial pearlitic carbon-silicon steel. Two-stage Q&P process, including full austenitization, at 220 °C, followed by two different temperatures, was applied as-received specimen generate composed tempered martensite, bainite...