Electrical Discharge Machining of Alumina Ceramic Matrix Composites Containing Electro-conductive Titanium Carbide as a Second Phase

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J. Korean Ceram. Soc. > Volume 34(10); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(10): 1092.

도전성 탄화티타늄 이차상을 포함하는 산화알루니늄기 세라믹 복합체의 방전가공

윤존도, 왕덕현¹, 안영철², 고철호

경남대학교 무기재료공학과
¹경남대학교 재료공학부
²경남대학교 화학공학과

Electrical Discharge Machining of Alumina Ceramic Matrix Composites Containing Electro-conductive Titanium Carbide as a Second Phase

ABSTRACT

Electrical discharge machining (EDM) was attempted on a ceramic matrix composite containing non-conductive alumina as a matrix and conductive titania as a second phase, and was found successful. As the current or duty factor increased, the material removal rate (MRR) increased and the surface roughness also increased. The EDMed surface was covered with a number of craters of a circular shape having 100-200 microns of diameter. The melting and evaporation was suggested for the EDM mechanism. The bending strength decreased 44% after EDM, but the Weibull modulus increased more than twice. Combination of EDM and barre이 polishing resulted in the maintenance of the bending strength level. Temperature distribution near a spark in the sample was computer-simulated by use of finite element method, and was found to have similar shape to the one which the observed craters have.

Key words: Electrical discharge machining, Ceramic matric composites, Material removal rate, Bending strength, Weibull modulus