Isothermal transformation studies on the effect of alloying elements (Mo, Ni, Cr, Mn, Al, Si, Co) in steels on the kinetics of the austenite to bainite transformation

Technical Report · Wed Dec 01 04:00:00 EST 1976

OSTI ID:5348804

Llopis, A M

Thermodilatomeric experiments were performed on seven Fe-C-X ternary systems (where X = Mo, Ni, Cr, Mn, Al, Si, Co) at different alloy concentrations. TTT diagrams for the isothermal decomposition of austenite in the bainite range were obtained. Extension of these experiments included combinations of some of the alloying elements such as Fe-C-Mo-Ni, Fe-C-Mo-Cr, Fe-C-Ni-Cr in order to determine what their interaction effects were in the bainite transformation. All the alloying elements studied accelerated the austenite decomposition for isothermal treatments just above the M/sub s/ giving for the reaction start curve an S-like curve. Present results indicated that Mn, Ni, Cr and Al retarded the bainite reaction. The bainite reaction below 500/sup 0/C was unaffected by Si when present by itself and was accelerated by the presence of Co, and by the presence of Mo to a lesser degree. Combined additions had a synergistic effect on reaction start times for the isothermal decomposition of the austenite and suggested interaction effects (e.g., Ni-Cr, Mo-Cr, Mo-Ni systems). However, the effect of three combined additions on kinetics of further stages of transformation was less well defined.

• Research Organization: California Univ., Berkeley (USA). Lawrence Berkeley Lab.
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5348804
• Report Number(s): LBL-6068
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
AUSTENITE
BAINITE
CARBON ADDITIONS
CARBON STEELS
CHROMIUM ALLOYS
COBALT ALLOYS
CRYSTAL-PHASE TRANSFORMATIONS
HIGH TEMPERATURE
IRON ALLOYS
IRON BASE ALLOYS
MANGANESE ALLOYS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
PHASE TRANSFORMATIONS
SILICON ALLOYS
STEELS
TERNARY ALLOY SYSTEMS