The determination of transducer location and ultrasonic wave propagation through temperature gradients in fillet are welding

온도구배가 있는 필릿용접에서 초음파의 전파와 탐촉자의 위치 결정

  • 정선국 (거제전문대학, 기계과) ;
  • 조형석 (한국과학기술원 기계공학과)
  • Published : 1997.06.01

Abstract

The temperature gradient in weldment changes the transit time and distorts the direction of the ultrasound beam to the higher temperature regions due to the lower sound speed in the hotter regions of the weldment. This paper describes a ray-tracing method for calculating the effects of temperature gradients on ultrasonic propagation in fillet arc weldig. In the method, weldment is conceptually devided into a number of layers and the refraction and sound speed at each layer is calculated using the temperature which calculated from analytical solution. Calculating the time and location of echoes arrived from various interfaces around a molten weld pool determines the optimum location of ultrasonic transducers and the correct position of flaws.

Keywords

References

  1. Welding design and fabrication Know your welding NDT-Ultrasonic testing Carl R. Weymueller
  2. Materials Evaluation v.52 Laser ultrasound directivity in CS-3 Ceramic George M. Graham;J. Yang;Charles Ume
  3. Materials Evaluation v.53 Narrow-band hybrid pulsed laser/EMAT system for noncontact ultrasonic inspection using angled shear waves Douglas A. Oursler;James W. Wagner
  4. Materials Evaluation v.49 Noncontact acousto-ultrasonics using laser generation and laser interferometric detection R. D. Huber;R. E. Green
  5. Materials Evaluation v.47 Closed loop process control of weld penetration using real-time radiography S. I. Rokhlin;K. Cho;A. C. Guu
  6. Materials Evaluation v.42 Ultrasonic detection of molten/solid interfaces of weldpools L. A. Lott
  7. Journal of Nondestructive Evaluation v.6 no.3 Ultrasonic wave propagation in temperature gradients J. A. Johnson;N. M. Carlson;L. A. Lott
  8. Proc. Instn. Mech. Engrs v.211 no.B3 An analytical solution for transient temperature distribution in fillet arc welding including the sffect of molten metal, Journal of Engineering Manufacture S. K. Jeong;H. S. Cho
  9. 대한용접학회지 v.13 no.2 필릿용접 공정에서 온도분포 예측을 위한 해석적 모델 정선국;조형석
  10. 대한용접학회지 v.13 no.3 용착금속을 고려한 필릿용접 공정에서 온도분포 예측을 위한 해석적 모델 정선국;조형석
  11. Welding Journal v.69 Control of GMAW: Detection of discontinuities in the weld pool N. M. Carlson;J. A. Johnson;D. C. Kunerth
  12. Velocity-temperature curve for longitudinal waves in 4620 steel Panametrics