The invention relates to
environmental protection type insulating
coating used for cold rolling non-orientation
silicon steel and the preparation method of a
coating layer thereof. The components of the insulating
coating comprise
phosphate, molybdenate, water, organic resin,
silane coupler and glycerine; the weight ratio of each component is as follows: 100 parts of
phosphate, 3 to 20 parts of molybdenate, 800 to 1500 parts of water, 20 to 50 parts of organic resin, 0.5 to 5 parts of
silane coupler and 8 to 15 parts of glycerine. The preparation method of the coating has the following steps:firstly, the insulating coating is coated on the surface of the cold rolling non-orientation
silicon steel; secondly, baking and
drying: the baking temperature is 150 to 300 DEG C; thirdly,
sintering: the
sintering temperature is 400 to 600 DEG C, and the
sintering time is 30 to 90 seconds; fourthly, finished product. The insulating coating of the invention contains no damaging element, the coating layer of the invention has good insulating property simultaneously, the adhesivity and the
corrosion resistance are good, and the insulating coating of the invention has good
punching shear workability and good
weldability, and can bear the
heat resistance of eliminating stress annealing. The operation of the method in the invention is simple, the coating layer prepared by the method has the good
punching shear workability and the good
weldability, and can bear the
heat resistance of eliminating the stress annealing.