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Effect of the Gmaw and the Gmaw-P Welding Processes on Microstructure, Hardness, Tensile and Impact Strength of Aisi 1030 Steel Joints Fabricated by ASP316 L Austenitic Stainless Steel Filler Metal

Kurşun T.

Archives of Metallurgy and Materials

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2011

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Vol. 56, iss. 4

955-963

EN

In this study, medium-carbon steel (AISI 1030) plates of 10 mm thickness, were welded by using the synergic controlled pulsed (GMAW-P) and manual gas metal arc (GMAW) welding techniques. Constant wire feed speed, voltage, welding speed and gas flow rates (3.2 m/min, 22.5 V, 4 mm/s, 16 1/min) and ASP316L austenitic stainless steel filler metal were used in these techniques. The interface appearances of the welded samples were examined by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-Ray diffraction (X-RD). In order to determine mechanical properties of samples, the tensile, impact and microhardness tests were conducted. The GMAW-P joints of AISI 1030 steel couples showed superior tensile strength, less grain growth and narrower heat affected zone (HAZ) when compared with GMAW joints, and this was mainly due to lower heat input, fine fusion zone grain and higher fusion hardness.

PL

W pracy, płyty ze średniowęlowej stali (AISI 1030) o grubości 10 mm były spawane technikami impulsowego (GMAW-P) i recznego spawania w gazie (GMAW). W obu technikach wykorzystano stała predkosc podawania drutu, napiecie, szybkość spawania i wielkość przepływu gazu (odpowiednio: 3.2 m/min, 22.5 V, 4 mm/s, 16 l/min), oraz austenityczna stal nierdzewna ASP316L jako spoiwo. Otrzymane próbki spoin badane były za pomoca mikroskopii optycznej, skaningowej mikroskopii elektronowej i mikroanalizy rentgenowskiej, oraz dyfrakcji rentgenowskiej. W celu okreslenia właściwosci mechanicznych próbek wykonano próby rozciagania, udarnosci i mikrotwardosci. Złacza otrzymane technika spawania impulsowego charakteryzuja sie wyzsza wytrzymałoscia na rozciaganie, mniejszym wzrostem ziarna i wezsza strefa wpływu ciepła w porównaniu do złaczy otrzymanych technika spawania recznego. Jest to spowodowane głównie mniejsza iloscia ciepła, drobnym ziarnem w przetopionej strefie i jej większą twardością.

2

Detection of short circuit in pulse gas metal arc welding process

Yarlagadda P. K. D. V., Praveen P., Madasu V. K., Rhee S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 1

328-332

EN

Purpose: The paper discusses several methods of detecting occurrence of short circuit and short circuit severity in pulse gas metal arc welding process (GMAW-P). Design/methodology/approach: Welding experiments with different values of pulsing parameter and simultaneous recording of high speed camera pictures and welding signals (such as current and voltage) were used to identify the occurrence of short circuit and its severity in GMAW-P process. The investigation is based on the measurement of welding signals specifically current and voltage signals and their synchronization with high speed camera to investigate the short circuit phenomenon in GMAW-P process. Findings: The results reveal that short circuit can be detected using signal processing techniques and its severity can be predicted by using statistical models and artificial intelligence techniques in GMAW-P process. Research limitations/implications: Several factors are responsible for short circuit occurrence in GMAW-P process. The results show that voltage and current signal carry rich information about the metal transfer and especially short circuit occurrence in GMAW-P process. Hence it's possible to detect short circuit occurrence in GMAW-P process. Future work should concentrate on development of advance techniques to improve reliability of techniques mentioned in this paper for short circuit detection and prediction in GMAW-P process. Originality/value: For achieving atomization of the welding processes, implementation of real time monitoring of weld quality is essential. Specifically for GMAW-P process which is widely used for light weight metal which is widely gaining popularity in manufacturing industry. However, in case of GMAW-P process hardly any attempt is made to analyse techniques to detect and predict occurrence of short circuit. This paper analyses different techniques that can be employed for real time monitoring and prediction of short circuit and its severity in the GMAW-P process.

3

Characterization of dynamic behaviour of short circuit in pulsed Gas Metal Arc Welding of aluminium

Praveen P., Kang M. J., Yarlagadda K. D. V. P.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 14, nr 1-2

75--82

EN

Purpose: This paper studies dynamic characteristics of short circuit in the pulsed current gas metal arc welding (GMAW-P). Design/methodology/approach: Welding experiments with different values of pulsing parameter and simultaneous recording of high speed camera pictures and welding signals (such as current and voltage) were used to identify different short circuit conditions in GMAW-P. The investigation is based on the synchronization of welding signals and high speed camera to characterize different types of short circuit occurring in GMAW-P system. The behaviour of short circuit under the influence of different pulsing conditions is also investigated. Findings: It will be shown in the paper that short circuit in GMAW-P occurs in different forms which can be categorized depending upon time of short circuit and phase (peak or base time) of the pulse. Further investigation involves study of the dynamic behaviour of short circuit with variation of different pulsing parameters. Research limitations/implications: The results show that by varying the pulse parameters, behaviour of short circuit in GMAW-P is changed. The pulse parameters can be adjusted to avoid occurrence of short circuit in GMAW-P. Future work should concentrate on development of practical indices in terms of pulse welding parameters for quantitative estimation of short circuit occurrence and avoidance. Originality/value: Determination of proper working parameters with GMAW-P is crucial for the appropriate selection of pulse welding parameters. As short-circuiting is common between the welding electrode and the workpiece in GMAW-P, so in order to estimate the working parameters and ensure stable GMAW-P understanding dynamic behaviour of short circuit in GMAW-P will be useful. However, in case of aluminum hardly any attempt is made to analyse the dynamic behaviour of short circuit in GMAW-P. This paper analyses the short circuit phenomenon in GMAW-P and their behaviour with varying pulsing parameters.