Anisotropy, as a rule, can be induced by annealing or rolling, texture, stress and often associated with the emergence of nanocrystallinity in the material. Various types of heat treatment (including thermomagnetic) cause different impacts on the effects of anisotropy and coercive force. Especially in soft magnetic materials, the coercivity primarily associated with the processes of displacement of domain walls.
For more details, You may find it useful to read the works of Dr. Potapova and others:
MAGNETIC PROPERTIES AND TEMPERATURE STABILITY OF A MOLYBDENUM-DOPED FINEMET-TYPE ALLOY
EFFECT OF THERMOMAGNETIC AND THERMOMECHANICAL TREATMENTS ON THE MAGNETIC PROPERTIES AND STRUCTURE OF THE NANOCRYSTALLINE SOFT MAGNETIC ALLOY FE81SI6NB3B9CU1
Physics of the Solid State. 2013. V.55. No 3. P. 508-519.
FE- AND CO-BASED NANOCRYSTALLINE SOFT MAGNETIC ALLOYS MODIFIED WITH HF, MO, AND ZR: MAGNETIC PROPERTIES, THERMAL STABILITY, AND STRUCTURE. ALLOYS (FE 0.6CO0.4)86HF7B6CU 1 AND (FE0.7CO0.3)88HF 7B4CU1
The Physics of Metals and Metallography. 2013. V.114. No 2. P. 129-137. 4
FE- AND CO-BASED NANOCRYSTALLINE SOFT MAGNETIC ALLOYS MODIFIED WITH HF, MO, AND ZR: MAGNETIC PROPERTIES, THERMAL STABILITY, AND STRUCTURE. ALLOY (FE 0.7CO0.3)88HF4MO2ZR 1B4CU1