晶界特征和结构的形成.pdf

Acta Materialia 53 (2005) 5213–5221 Grain boundary characteristics and texture formation in a medium carbon steel during its austenitic decomposition in a high magnetic field Y.D. Zhang a,b, C. Esling b,*, J.S. Lecomte b, C.S. He a, X. Zhao a, L. Zuo a a Key Laboratory of Electromagnetic Processing of Materials (Ministry of Education), Northeastern University, Shenyang 110004, PR China b LETAM, CNRS-UMR 7078, University of Metz, Ile du Saulcy, 57045 Metz, Moselle, France Received 12 April 2005; received in revised form 30 July 2005; accepted 2 August 2005 Available online 19 September 2005 Abstract A 12-T magnetic field has been applied to a medium plain carbon steel during the diffusional decomposition of austenite and the effect of a high magnetic field on the distribution of misorientation angles, grain boundary characteristics and texture formation in the ferrite produced has been investigated. The results show that a high magnetic field can cause a considerable decrease in the fre- quency of low-angle misorientations and an increase in the occurrence of low R coincidence boundaries, in particular the R3 of fer- rite. This may be attributed to the elevation in the transformation temperature caused by the magnetic field and, therefore, the reduction of the transformation stress. The wider temperature range for grain growth offers longer time to the less mobile R bound- aries to enlarge their areas. Moreover, the magnetic field can enhance the transverse field-direction fiber (Æ0 0 1æiTFD). It can be assumed that the effects of the field were caused by the dipolar interaction betwe