An analysis is made of the heating and melting of the surfaces of cera
mic samples of aluminium nitride, silicon nitride, and boron nitride b
y low-intensity laser radiation. It is shown that the thickness of a m
olten surface layer is governed by the thermophysical properties of th
e material and by the relationship between its melting point and the i
ntense-evaporation temperature. The derived dependence of the thicknes
s of the molten layer on the radiation intensity is compared with the
results of experiments on melting I of aluminium nitride. The publishe
d experimental results on the laser heating of silicon nitride and bor
on nitride are interpreted.