Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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Evaluation of Reheat Cracking Susceptibility with Simulated Heat Affected Zones in Cr-Mo-V Turbine Rotor Steel

CrMoV 터빈로터강에서 모의 열영향부 시험편을 이용한 재열균열 민감도평가

  • Published : 1995.03.01
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Abstract

The evaluation of reheat cracking susceptibility in CrMoV turbine rotor steel was performed using thermally simulated heat affected zones. The examinations were carried out in terms of microstructural characterization, microhardness measurement and a Charpy type notch opening three point bend test. It was found that reheat cracking susceptibility increased as the peak temperature increased. This effect was due to the combined effects of the carbide dissolution and unrestricted grain growth at 1350.deg. C peak temperature. Reheat cracking susceptibility was estimated based on microhardness measurement and prior austenite grain size. It was established that for this particular material, reheat cracking in coarse grained heat affected zone can be eliminated if the microhardness is below about 360DPH and the grain size is below about 30.mu.m. It is evident that reheat cracking susceptibility can be eliminated or reduced by carefully controlling the welding parameters such that a refined structure is produced in the coarse grained heat affected zone.

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References

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