Determination of welding parameter dependent hot cracking susceptibility of 5086-h32 aluminium alloy with the use of mvt method

Batıgün, Caner
Hot cracking is a serious problem that encounters during welding of aluminium-magnesium alloys. In the present study, solidification and liquation type of hot cracks in weld metal and the heat-affected zones of 5086-H32 aluminium alloy were investigated by using Modified Varestraint Test (MVT) with TIG-AC and TIG-DC welding. With determining the size, type and number of cracks, a relation was established between welding line energy and strain on the hot crack formation. This information was used to determine the hot crack safe parameter ranges. The hot cracking tendency as a function of applied parameters were discussed in the frame of temperature fields around the moving heat source. Moreover, the characteristic hot crack locations on the 5086-H32 MVT specimens were generalized. The results of the study indicated that the increase in line energy and strain increased the hot cracking tendency of the specified aluminium alloy. In the low line energy range, the main hot cracking mechanism is the solidification cracking which could be overcome by the use of a suitable filler material. At high line energy range, due to the increased amount of interdendritic liquid, the amount of solidification cracking decreases by healing mechanism. However, because of the enlarged-temperature-field around the weld zone, fraction of HAZ cracking increases. The comparison between the hot cracking tendencies in low and high line energies indicates that the low line energy ranges with low augmented strains resulted in hot crack safer parameters.


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Gür, Cemil Hakan; Yelbay, Hasan İlker; Çam, İbrahim (2010-06-11)
Residual stresses have significant inflences on the service performance of the welded components. Various studies have been continuing to develop nondestructive methods for determination of residual stresses with portable equipment and short measurement time, as an alternative to the existing techniques such as X-ray diffraction. This study aims to investigate the applicability of Magnetic Barkhausen Noise method on predicting surface residual stresses in the welded steel plates.
Investigating the effects of subsequent weld passes on surface residual stresses in steel weld merits by Magnetic Barkhausen Noise technique
Gür, Cemil Hakan; Batıgün, Caner; Çam, İbrahim (American Society of Nondestructive Testing, 2016-03-01)
Investigating the Effects of Subsequent Weld Passes on Surface Residual Stresses in Steel Weldments by Magnetic Barkhausen Noise Technique
Gür, Cemil Hakan; Batıgün, Caner; Çam, İbrahim (2016-03-01)
Variations of surface residual stresses with subsequent weld passes were investigated in API 5L X70 steel plates by the magnetic barkhausen noise (MBN) technique. The plates were welded by applying a number of different passes under fully clamped conditions. After each weld pass, the MBN signal and hardness distributions on the front and back surfaces of the plates were measured. A specific calibration procedure and setup were used for conversion of the MBN signals into elastic stress values. The results we...
Non-destructive determination of residual stress state in steel weldments by Magnetic Barkhausen Noise technique
Yelbay, Hasan İlker; Çam, İbrahim; Gür, Cemil Hakan (2010-01-01)
The purpose of this study is non-destructive determination of residual stresses in the welded steel plates by Magnetic Barkhausen Noise (MBN) technique. A MBN-stress calibration set-up and a residual stress measurement system with scanning ability were developed. To control the accuracy and the effectiveness of the developed system and procedure, various MBN measurements were carried out. The MBN results were verified by the hole-drilling method. Microstructural investigation and hardness measurements were ...
Citation Formats
C. Batıgün, “Determination of welding parameter dependent hot cracking susceptibility of 5086-h32 aluminium alloy with the use of mvt method,” Ph.D. - Doctoral Program, Middle East Technical University, 2005.