Determination Of Optimum Test Parameters Of Welding Defects In Ultrasonic Method
In this study, 30 mm thick steel specimens (St 37-2) with X, Y, V and L-shaped grooves were welded using electric arc welding with coated electrode. Different types of weld defects (slag inclusions, porosity and longitudinal crack) were artificially produced in the welds. Ultrasonic examination of the welds were carried out by varying parameters such as probe angle, frequency and meassuring position to find their optimum values. The ultrasonic tests were conducted by using pulse-echo type ultrasonic equipment and probes with 2-4 MHz frequencies, 450-600 and 700 angles according to A-Scan inspection mode.
For each type of artificial defect, optimum test parameters such as probe angle, frequency and meassuring position at gain levels according to 40% of screen height were evaluated. It was found that the optimum parameters were obtained by using 2 MHz probe with 45o angle. The best signals were received when back wall echo was eliminated in a shortest distance in single step. In all of the tests, the effects of probe angle, frequency and meassuring position on the gain levels were clearly observed.
BODUR İlknur ,
Danışman : Yrd. Doç. Dr. Selim YILDIRIM
Anabilim dalı : Metalurji ve Malzeme Mühendisliği
Yılı : 2006
Tez savunma Jürisi : Yrd. Doç. Dr. Selim YILDIRIM (Danışman)
Prof. Dr. Enver OKTAY
Prof. Dr. İbrahim YUSUFOĞLU
Prof. Dr. T.Osman ÖZKAN
Prof. Dr. Şerafettin EROĞLU
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