Interpretation of Stresses in the Glass Bonded Ferrites by Vickeres Indentation Method

Vickeres Indentation법에 의한 페라이트와 접합유리에서의 응력해석

  • 안정환 (아주대학교 재료공학과) ;
  • 제해준 (한국과학기술연구원 세라믹스부) ;
  • 홍국선 (한국과학기술연구원 세라믹스부) ;
  • 안재환 (아주대학교 재료공학과) ;
  • 고경현 (아주대학교 재료공학과)
  • Published : 1993.06.01

Abstract

Residual stresses is one of the major factors to degrade the magnetic properties of VCR magnetic heads. Vicker's indentation technique was adapted to estimate the residual stresses Residual stresses and distribution in the glass and ferrite were obtained after bonding ferrite with glass, varing the cooling rate. The compressive and tensile stresses were developed in the interface and gradually decreased with increasing distance from the interface. The stresses were decreased with a cooling rate. The mean values of residual stress in ferrite were 10MN/㎡, 8MN/㎡, 5MN/㎡ with cooling rate 10℃/min, 5℃/min, 1℃/min respectively. When the bonded sample was annealed above the glass transition temperature followed by cooling at 5℃/min cooling rate, the residual stress was reduced to 6MN/㎡.

Keywords

References

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