The reasons for welding stainless steel with argon arc welding:
1, argon protection can be isolated from the air oxygen, nitrogen, hydrogen and other undesirable effects on the arc and the molten pool, reduce the alloying elements of the burned, in order to get dense, no spatter, high quality welded joints.
2, argon arc welding arc combustion stability, heat concentration, high arc column temperature, high welding productivity, narrow heat-affected zone, welded weldments stress, deformation, crack tendency is small.
3, argon arc welding for open arc welding, operation, observation and convenient.
4, electrode loss is small, the arc length is easy to maintain, welding without flux, coating layer, so it is easy to realize mechanization and automation.
5, argon arc welding can weld almost all metals, especially some refractory metals, easy to oxidize metals, such as magnesium, titanium, molybdenum, zirconium, aluminum and its alloys.
6, not subject to the position of the weldment, can be all-position welding.
Expanded Information:
Argon arc welding is suitable for welding easily oxidized non-ferrous metals and alloy steels (mainly with Al, Mg, Ti and its alloys and stainless steel welding).
Stainless steel can not be welded with carbon steel electrodes for the following reasons:
1, stainless steel welding with carbon steel electrodes is prone to intergranular corrosion.
2, carbon steel electrodes in the oxides make it more oxidizing, while the weld metal contains more oxygen, so that the alloying elements of the greater burn.
3, carbon steel electrode flux skin contains more silica, a part of silicon in the form of silicon oxide inclusions in the weld, resulting in poorer mechanical properties of the weld, especially plasticity and impact toughness than alkaline electrodes low.
4, carbon steel welding rod flux skin does not contain fluorite (CaF2), low dehydrogenation capacity; weld metal with high hydrogen content, poor resistance to cold cracking, and desulfurization of the weld in the element of manganese content is low, the effect of desulfurization is poor.
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