METHOD OF PRODUCTION OF VARISTOR CERAMICS BASED ON ZINC OXIDE Russian patent published in 2015 - IPC C04B35/453 B82B3/00 H01C7/10 

FIELD: metallurgy.

SUBSTANCE: initial components in form of solid phase hydrated nitrates of zinc, bismuth, aluminium, cobalt, chrome, manganese and commercial sugar as fuel are mixed, at that sugar consumption is 0.5-0.6 weight parts per 1 weight part of produced nanocrystalline powder. Tartrate solution of stibium with concentration 0.098-0.102 g/ml Sb₂O₃ is added, and chemical combustion of mixture at 140-150°C is performed for 40-50 minutes. The combustion product is baked at 690-710°C for 50-70 minutes with production of the nanocrystalline powder, it is wetted by 5% polyvinyl alcohol, and the powder cold pressing at pressure 125-156 MPa is performed with production of raw-tablet. Then its two-stage sintering at 690-710°C for 50-60 minutes is performed at the first stage, and at 920-930°C for 230-250 minutes at the second stage with production of the varistor ceramics.

EFFECT: increased breakdown potential and nonlinearity factor upon use of cold pressing.

3 cl, 5 ex