In-process detection of weld defects using laser-based ultrasound

نویسندگان

  • Stephen W. Kercel
  • Roger A. Kisner
  • Marvin B. Klein
  • G. David Bacher
  • Bruno Pouet
چکیده

Laser-based ultrasonic (LBU) measurement shows great promise for on-line monitoring of weld quality in tailor-welded blanks. Tailor-welded blanks are steel blanks made from plates of differing thickness and/or properties butt-welded together; they are used in automobile manufacturing to produce body, frame, and closure panels. LBU uses a pulsed laser to generate the ultrasound and a continuous wave (CW) laser interferometer to detect the ultrasound at the point of interrogation to perform ultrasonic inspection. LBU enables in-process measurements since there is no sensor contact or near-contact with the workpiece. The authors are using laser-generated plate (Lamb) waves to propagate from one plate into the weld nugget as a means of detecting defects. This paper reports the results of the investigation of a number of inspection architectures based on processing of signals from selected plate waves, which are either reflected from or transmitted through the weld zone. Bayesian parameter estimation and wavelet analysis (both continuous and discrete) have shown that the LBU time-series signal is readily separable into components that provide distinguishing features which describe weld quality. The authors anticipate that, in an on-line industrial application, these measurements can be implemented just downstream from the weld cell. Then the weld quality data can be fed back to control critical weld parameters or alert the operator of a problem requiring maintenance. Internal weld defects and deviations from the desired surface profile can then be corrected before defective parts are produced.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A Laser-Based Vision System for Weld Quality Inspection

Welding is a very complex process in which the final weld quality can be affected by many process parameters. In order to inspect the weld quality and detect the presence of various weld defects, different methods and systems are studied and developed. In this paper, a laser-based vision system is developed for non-destructive weld quality inspection. The vision sensor is designed based on the ...

متن کامل

Vulnerability Assessment of Steel Structures in District 12 of Mashhad City and Prioritizing the Welding Defects Using the Analytic Hierarchy Process

Recently, steel structures have been accounted for a large percentage of the buildings due to their advantages such as higher execution speed and easier construction. In steel structures, welded joints are commonly used and their quality plays a key role in stability of buildings under applied loads. Hence, to increase resiliency of welded steel structures against natural hazards, welded joints...

متن کامل

MICROSTRUCTURAL STUDIES ON LASER WELDING OF INCONEL 718 TO 2304 DUPLEX STAINLESS STEEL WITH A FOCUS ON OPTIMAZING PROCESS PARAMETERS AND ACHIEVING THE MAXIMUM FRACTURE STRENGTH

In this research, microstructure and mechanical properties of laser welded joints between 2304 duplex stainless steel and Inconel 718 nickel-based super alloy were investigated. Microstructural evolution in the various areas of welded joints and also the effect of welding parameters on the mechanical properties of dissimilar joints were studied. Response surface methodology based on the central...

متن کامل

Numerical simulation of laser beam welding of Ti6Al4V sheet

This paper was aimed to report the 3D finite element analysis simulation of laser welding process of Ti6Al4V 1.7 mm sheets in butt joint in order to predict the temperature distribution, hardness, and weld geometry. The butt-joint welds were made using CO2 laser with the maximum power of 2.2 kW in the continuous wave mode. A part of the experimental work was carried out to verify the weld geome...

متن کامل

Dissimilar laser welding of NiTi shape memory alloy to austenitic stainless steel archwires

In this research, dissimilar welding of NiTi shape memory alloy to AISI 304 austenitic stainless steel Archwires was investigated. For this purpose, common straight orthodontic archwire with rectangular cross-section and dimensions of (0.635 × 0.432 mm) were selected and the laser welding technique was used to connect the wires. The microstructure, chemical composition and phasesin the weld zon...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1999