SECONDARY RECRYSTALLIZATION IN FE-3-PERCE NT-SI CONTAINING AIN AS INHIBITOR

Fe-3%Si containing AlN, which was cold-rolled with 84.7% reduction and primarily recrystallized, was heated with the heating rate of 15-degr ees-C/h in the 85%H-2-N2 (condition A) or in the 5%H-2-N2 atmosphere ( condition B) up to a temperature of 1200-degrees-C and extracted from 925-degrees-C at intervals of 50-degrees-C. The secondarily recrystall ized grains were observed at 975-degrees-C in condition A, while no se condarily recrystallized grains were found in condition B at this temp erature. The secondary recrystallization was completed at 1025-degrees -C in both conditions. No (101) [010] oriented secondary grains were o bserved in specimen A extracted at 975-degrees-C. However, the main se condarily recrystallized texture at 1025-degrees-C was (101) [010] in both conditions. The scatter from the ideal (101) [010] orientation wa s smaller and the grain size was larger in B condition compared with c ondition A at this stage. However, the scatter in condition B was larg er compared with the one processed from the primarily recrystallized s pecimen containing both AlN and MnS as inhibitors. These results are d iscussed from the viewpoint of grain boundary migration characteristic s of coincidence boundaries and the following conclusion were derived. (1) In the weaker inhibitor condition, selective migration of other t han SIGMA9 type boundaries occurs in the lower temperature range and s elective migration of SIGMA9 type boundaries mainly occurs over a high er temperature range. (2) In the stronger inhibitor condition, selecti ve migration of grain boundaries initiates over the higher temperature range and they are mainly SIGMA9 type boundaries.