الفهرس 
Chapter 1 introductionOnly 14 pages are availabe for public view
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Abstract
The mechanical and corrosion performances of carbon steel arc weld joints in service environments have been established to be influenced by the process parameters used in carrying out the welding process. Gas Metal Arc Welding (GMAW) and Shielded Metal Arc Welding (SMAW) processes are leading in the development of arc welding process which are higher productivity, common and good in quality. In this study, the effects of different welding parameters on welding penetration, microstructe, hardness and corrosion resistance measurement for welding carbon steel by gas metal arc welding and shielded metal arc welding are investigated. The variables were chosen in this study are welding process, arc voltage, welding current and corrosion environment .The base metal seamless pipe carbon steel is ASME A106 grade B that having the 7.1mm wall thickness of base metal (ASME A106) was used. In SMAW process, the arc voltage ranges from 27 to 38 V. However, the current ranges from 50 to 100. The speed was constant (100 mm/min). In GMAW process, the arc voltage ranges from 28 to 34 V. However, the current ranges from 130 to 180. The speed was constant (200 mm/min). The penetration, microstructure and micro-hardness were determined with the aid of Vickers micro-hardness tester for each specimen after the welding process and the effect of it was studied. Then studied the effect of two corrosion environment on carbon steel. The corrosion of the samples in atmospheric corrosion and soil were investigated using mass loss. The results showed the weld bead shape varied directly with the welding process. The microstructure of the weld joints consists of ferrite and pearlite phases. The heat input affects the weld joint hardness negatively. The corrosion performance of the weld joints is decreased with the increase in the heat energy input. Atmospheric medium more aggressive than soil medium.