The　ZrC-C　peritectic　fixed　point　has　a　very　high　nominal　phase　transition　temperature　(2　882　℃),　which　is　higher　than　the　upper　limit　of　most　high-temperature　heating　furnaces.　By　improving　the　self-designed　HT271　heating　furnace,　the　upper　limit　of　its　working　temperature　was　increased　to　above　2　900　℃,　which　met　the　requirements　of　the　ZrC-C　peritectic　fixed　point　experiments.　ZrC　powder　and　C　powder　were　used　to　configure　the　mixed　powder,　and　the　filling　and　realizing　experiments　of　the　ZrC-C　peritectic　fixed　point　were　carried　out,　two　sets　of　realizing　cycle　data　were　obtained.　The　result　of　the　first　cycle　is　better:　the　inflection　point　temperature　is　2　882.298　℃;　the　inflection　point　uncertainty　is　26.3　mK.　It　has　been　verified　that　at　a　temperature　above　2　900　℃,　the　improved　HT271　heating　furnace　can　be　used　for　about　30　minutes　stably.　In　order　to　extend　the　stable　use　time　of　the　HT271　furnace　at　extremely　high　temperature,　the　next　improvement　plan　is　proposed.　©　2022,　Acta　Metrologica　Sinica　Press.　All　right　reserved.