Measurement of kinetics of Nb(C,N) precipitation using hot torsion testing

• Published in: Scripta metallurgica et materialia Vol. 29; no. 7; pp. 881 - 884
• Main Authors: Silveira e Silva, J.M, Barbosa, R
• Format: Journal Article
• Language: English
• Published: Seoul Elsevier B.V 01.10.1993; Oxford Pergamon Press; New York, NY
• Subjects: 360202 - Ceramics, Cermets, & Refractories- Structure & Phase Studies; ALLOYS; Applied sciences; AUSTENITIC STEELS; CARBIDES; CARBON COMPOUNDS; Condensed matter: structure, mechanical and thermal properties; DEFORMATION; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; IRON ALLOYS; IRON BASE ALLOYS; KINETICS; MATERIALS SCIENCE; Metals. Metallurgy; MICROSTRUCTURE; NIOBIUM CARBIDES; NIOBIUM COMPOUNDS; NIOBIUM NITRIDES; NITRIDES; NITROGEN COMPOUNDS; Physics; PNICTIDES; PRECIPITATION; REFRACTORY METAL COMPOUNDS; SEPARATION PROCESSES; Solubility, segregation, and mixing; phase separation; STEELS; TORSION; TRANSITION ELEMENT COMPOUNDS; Precipitation; Microalloyed steel; Torsion test; Temperature effect; Stress relaxation test; Kinetics; High temperature; Experimental study; Niobium Carbides nitrides
• ISSN: 0956-716X
• DOI: 10.1016/0956-716X(93)90375-3

Hot torsion stress-relaxation tests can be used to detect P sub s values for austenite of niobium microalloyed steels. Measurement of P sub f times seem to be more difficult to obtain due to strain heterogeneity along the specimen radius inherent to the testing method. A PTT curve was obtained for a 0.026C--0.016Ti--0.11Nb--10 ppm N steel for a temperature range of 1023-1323K. Validation of the testing method was obtained by comparing the experimental data with a PTT curve predicted by Dutta and Sellars' model for strain induced precipitation.