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스플린터 및 판상형 티탄산칼륨염 합성 및 브레이크 보강재로서의 평가

Synthesis of splinter-type and plate-type potassium titanate as reinforcements in brake pad for automobile

  • Kim, Sung-Hun (Department of Advanced Materials Science and Engineering, Yonsei University) ;
  • Kim, Jong-Young (Icheon Branch, Korea Institution of Ceramic Engineering and Technology) ;
  • Shim, Wooyoung (Department of Advanced Materials Science and Engineering, Yonsei University) ;
  • Lee, Jung Ju (Advanced Research Team, Sangsin Brake R&D Institute) ;
  • Kwon, Sung Wook (Advanced Research Team, Sangsin Brake R&D Institute)
  • 투고 : 2019.11.11
  • 심사 : 2019.12.06
  • 발행 : 2019.12.31

초록

스플린터(splinter) 및 판상(plate shape) 형상을 가지는 티탄산칼륨염(K2O·nTiO2, PT)을 합성하고 브레이크 마찰재의 보강재로 이용하여 마찰 특성을 평가하였다. 스플린터형 티탄산칼륨염을 합성하기 위하여 먼저 판상 형상을 가지는 사티탄산칼륨염(K2O·4TiO2, PT4)을 합성하고 칼륨 이온(K+)을 일부 산침출(acid leaching)하여 육티탄산칼륨염(K2O·6TiO2, PT6)으로 변환시킨 후, 800℃에서 열처리하여 스플린터 형상의 입자를 얻었다. 판상형 티탄산칼륨염을 합성하기 위해서 염화칼륨을 융제로 사용하고 마그네슘(Mg)을 일부 첨가하여 판상의 형상을 가지는 마그네슘티탄산칼륨염(K0.8Mg0.4Ti1.6O4, PMT)을 합성하였다. 얻어진 육티탄산칼륨염 및 마그네슘티탄산칼륨염 입자를 보강재로 이용하여 브레이크 패드 마찰재를 제작하고 1/ 5-스케일 다이나모미터(scale dynamometer)를 이용하여 마찰 마모 특성을 평가하였다. 평가 결과, 두 종류의 보강재가 유사한 마찰계수 및 Fade & recovery 특성을 보였으며 판상형 마그네슘티탄산칼륨염의 경우, 스플린터형 육티탄산칼륨염보다 우수한 내마모성을 보이는 것을 알 수 있었다.

We synthesized potassium titanates having splinter and plate shape and evaluated frictional and wear properties of brake pad using them as reinforcements in friction materials. For splinter-shaped potassium titanates, potassium tetratitanate (K2O·4TiO2, PT4) with plate shape was prepared, then K ion of the titanate was leached by acid to make potassium hexatitanate (K2O·6TiO2, PT6), which was transformed to splinter-shaped PT6 by thermal treatment at 800℃. Plate-shaped potassium magnesium titanate (K0.8Mg0.4Ti1.6O4, PMT) was prepared by adding Mg in the potassium titanate using KCl as a flux. Using PT6 and PMT as reinforcements in friction materials of brake pad, we evaluated frictional and wear properties using 1/5-scale dynamometer. According to dynamometer test results, both reinforcements shows similar friction coefficient and fade & recovery behavior to conventional material and plate-shaped PMT exhibits higher wear resistance than splinter-shaped PT6.

키워드

참고문헌

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