The invention relates to the field of structural
ceramic manufacturing, in particular to a preparation method of
zirconium diboride ceramic with in-situ-introduced
boron as an additive. The preparation method comprises the following steps: firstly, performing ball milling and mixing
zirconium dioxide and elemental
boron in a mol ratio of (1: 3.5)-(1: 4.5), and
drying to obtain ZrO2 / B mixed
powder; secondly, putting the ZrO2 / B mixed
powder into a
graphite crucible, and performing high-heat treatment at the air pressure of below 200Pa to obtain ZrB2 / B
powder; and finally, sieving the obtained ZrB2 / B powder, performing isostatic pressing, putting the ZrB2 / B powder into the
graphite crucible, performing
pressureless sintering in an
argon atmosphere, controlling the
sintering temperature at 1800 -2100 DEG C, the heat-preserving time at 1-3 hours and the heating rate at 10-50 DEG C / min, and preserving heat for 0.5 hours at 1500-1700 DEG C to obtain the compact
zirconium diboride ceramic. By the preparation method, a ball milling medium is not introduced, the
impurity content is reduced, excellent performance of the
zirconium diboride ceramic can be maintained easily, and the
sintering compactness of the
zirconium diboride ceramic is realized at a relatively low temperature (2000 DEG C).