This invention discloses a high-performance meta-
aramid /
mica composite insulating paper and its preparation method. The paper is formed by wet
papermaking and
hot pressing of a mixed
slurry composed of meta-
aramid chopped fibers, meta-
aramid precipitated fibers, and
mica flakes. The composite insulating paper has a
thermal decomposition temperature ≥425℃, tensile strength ≥52N / mm, tear strength ≥2.2N / mm, and
voltage breakdown strength ≥13.8kV / mm. The
mass ratio of chopped fibers to precipitated fibers is (50~80):(50~20). The amount of
mica flakes added is 5wt%~10wt% of the total
mass of the two aramid fibers. The
hot pressing adopts a segmented
hot pressing process of "low-temperature pre-pressing - medium-temperature strengthening - high-temperature setting". By controlling the key parameters of the precipitated fibers and optimizing the ratio of chopped fibers to precipitated fibers and the proportion of mica flakes added, the paper is prepared through processes such as
raw material pretreatment, graded mixing and dissociation, wet
papermaking, and segmented hot pressing. Advantages: Through multi-parameter coordinated control and
process optimization, the technical bottlenecks such as the mechanical and insulation properties of existing aramid composite insulating paper and insufficient
thermal stability have been solved.