Yerli Borik Asitten Kalıntı Karbon İçermeyen Bor Karbür Sentezi

Bu çalışmada, yerli borik asit ve teknik kalite mannitol kullanılarak borik asidin esterifikasyonuyla sentezlenen jel öncü malzemeler üzerinden kalıntı karbon içermeyen bor karbür tozlarının üretimi karbotermik indirgeme yöntemiyle gerçekleştirilmiştir. Literatürdeki diğer çalışmalardan farklı olarak bor bileşenlerinin buharlaşması nedeniyle meydana gelen bor kayıpları, sisteme kalsiyum kaynağının eklenmesiyle önlenmiş ve jelleşme sırasında sistemdeki tüm borik asidin esterleşmesi için sistemin pH değeri sabitlenmiştir. Sentezlenen esterlerin kimyasal yapıları FTIR (Fourier Dönüşüm Kızılötesi Spektroskopisi) kullanılarak, termal özellikleri ise STA (Simultane Termal Analiz) ile incelenmiştir. Elde edilen tozların faz analizleri XRD (X-Ray Difraksiyonu), morfolojik özellikleri ve parçacık boyutları ise SEM (Taramalı Elektron Mikroskobu) ile analiz edilmiştir. Kalıntı karbon içermeyen bor karbür tozları 1350°C’de 6 saat Argon atmosferi altında gerçekleştirilen karbotermik indirgemeyle elde edilmiştir.

Synthesis of Boron Carbide Without Excess Carbon over Local Boric Acid

In this study, boron carbide powders without excess carbon were produced via carbothermic reduction over gel precursors synthesized by esterification of local boric acid and technical grade mannitol. Boron loss due to the volatilization of boron compounds was eliminated by addition of calcium source and pH value of system was fixed to esterify of all boric acid. Chemical structure of synthesized esters were studied with using FTIR (Fourier Transform Infrared Spectroscopy) and thermal properties also were studied with using STA (Simultaneous Thermal Analysis). Phase analysis of obtained powders were studied via XRD (X-Ray Diffraction) and particle size and morphology of powders also were investigated via SEM (Scanning Electron Microscopy). Boron carbide powders without excess carbon were obtained via carbothermic reduction at 1350°C for 6 hours under an argon atmosphere.

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