The Best Wear Solution Material_Flux Cored Welding Wires

Introduction on the influence of various alloying elements in the welding core on welding

1) Carbon (C) Carbon is the main alloying element in steel. When the carbon content increases, the strength and hardness of the steel increase significantly, while the plasticity decreases. In the welding process, carbon plays a certain role in deoxidation, and it chemically reacts with oxygen under the high temperature of the arc to generate carbon monoxide and carbon dioxide gas, which removes the air around the arc area and the molten pool to prevent oxygen and nitrogen in the air. Adverse effects on the molten pool, reducing the oxygen and nitrogen content in the weld metal. If the carbon content is too high, the reduction effect will be severe, which will cause large splashes and pores. Considering the effect of carbon on the hardenability of steel and its increased crack susceptibility, the carbon content of low carbon steel cores is generally 0.1%.

2) Manganese (Mn) Manganese is a good alloying agent in steel, and its strength and toughness will increase with the increase of manganese content. In the welding process, manganese is also a good deoxidizer, which can reduce the oxygen content in the weld. Manganese and sulfur combine to form manganese sulfide floating in the slag, thereby reducing the tendency of hot cracks in the weld. Therefore, the manganese content of the general carbon structural steel welding core is 0.30% to 0.55%, and the manganese content of some special-purpose steel wires is as high as 1.70% to 2.10%.

3) Silicon (Si) silicon is also a good alloying agent. Adding an appropriate amount of silicon to the steel can improve the yield strength, elasticity and acid resistance of the steel; if the content is too high, the plasticity and toughness will be reduced. In the welding process, silicon also has good deoxidation ability and forms silicon dioxide with oxygen, but it will increase the viscosity of the slag and easily promote the formation of non-metallic inclusions.

4) Chromium (Cr) Chromium can improve the hardness, wear resistance and corrosion resistance of steel. For mild steel, chromium is an incidental impurity. The main metallurgical feature of chromium is that it is prone to rapid oxidation to form the refractory oxide chromium trioxide (Cr2O3), which increases the possibility of weld metal inclusions. After the chromium trioxide transitions to the slag, the viscosity of the slag can be increased and the fluidity can be reduced.

5) Nickel (Ni) Nickel has a relatively significant effect on the toughness of steel. Generally, when the low temperature impact value is required to be high, some nickel is appropriately added.

6) Sulfur (S) Sulfur is a harmful impurity. With the increase of sulfur content, it will increase the hot crack tendency of the weld, so the content of sulfur in the welding core should not be greater than 0.04%. When welding important structures, the sulfur content shall not exceed 0.03%.

7) Phosphorus (P)