Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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Enhanced Superplasticity of Two-phase Titanium Alloys by Microstructure Control

2상 타이타늄 합금의 미세조직 제어를 통한 초소성 특성 향상

  • 박찬희 (포항공과대학교 신소재공학과) ;
  • 이종수 (포항공과대학교 신소재공학과)
  • Published : 2010.02.01
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Abstract

The current understanding for phase/grain boundary sliding and low-temperature/high-strain rate superplasticity of two-phase titanium alloys is summarized. The quantitative analysis on boundary sliding revealed increased sliding resistance on the order of ${\alpha}/{\beta}\;\ll\;{\alpha}/{\alpha}\;{\approx}\;{\beta}/{\beta}$ boundary, hence, led to the conclusion that approximately 50% alpha(or beta) volume fraction and/or grain refinement is beneficial for obtaining large superplastic elongation at low temperature and/or high strain rate. To predict the temperature for 50% alpha volume in various alpha/beta Ti, artificial neural network was applied. Finally, much enhanced superplasticity was achieved through grain refinement utilizing dynamic globularization.

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References

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