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Direct Observation of Crack Tip Stress Field Using the Mechanoluminescence of SrAl2O4:(Eu,Dy,Nd)

SrAl2O4(Eu,Dy,Nd) 압광체를 이용한 균열첨단에서의 응력장 가시화 연구

  • 김지식 (상주대학교 신소재공학과) ;
  • 손기선 (순천대학교 재료금속공학과)
  • Published : 2003.08.01

Abstract

The present investigation aims at visualizing the crack tip stress field using a mechanoluminescence material. The well known compound $SrAl_2O_4$:$Eu^{2+}$ was adopted as a mechanolurninescence material. Two more trivalent rare-earth elements such as Dy and Nd were taken into consideration as codopants to provide the appropriate trap levels. Samples of a variety of compositions were prepared by varing $Eu^{2+}$, $Dy^{3+}$, and $Nd^{3+}$ doping contents, for which the combinatorial chemistry method was used. In order to search for the optimum composition for the highest mechanoluminescence, the luminescence induced by a compressive device including a CCD camera. In parallel, a compact tension specimen was prepared by mixing the luminescence powders of optimum composition and epoxy resin. Crack initiation from the mechanically machined sharp note tip and its growth during loading were found to be associated with the extent of light emission from $SrAl_2O_4$.

Keywords

References

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