Description of flux for stainless steel surfacing. In this chapter, we provide customers with stainless steel, copper and alloy flux, nickel and its alloy flux, alloy surfacing flux, etc. The simple precautions are for reference. Our company can also provide Requires development of flux for special steel grades.
The stainless steel flux is not very targeted to the wire and the base material. A type of flux (such as ZT-SJ601, ZT-SJ260, etc.) can be used with a variety of stainless steel wires to weld the base material with the corresponding chemical composition and mechanical performance conditions; Fluxes for metals are highly targeted and should be fully verified before selecting a welding wire for welding. As a welding method for modifying the surface of materials, surfacing welding will naturally be applied to a variety of materials. Due to the diversity and complexity of the base material to be welded, the user should determine the flux on the basis of sufficient experiments.
Chromium-nickel stainless steel is liable to precipitate carbides after repeated heating during welding, thereby reducing corrosion resistance and mechanical properties. In order to prevent intergranular corrosion caused by overheating, welding should be performed with small current, small line energy input, and short arc thin track. Note that the electrical resistivity of stainless steel is large, and the possibility of welding penetration is also large, and it is easy to cause deformation.
Nickel and its alloys have poor thermal conductivity and are liable to cause coarse grains. Welding should be performed with a small current and small wire energy. Nickel is easily embrittled by sulfur and lead to form thermal cracks. Therefore, impurities such as oil, rust, paint, dust, and moisture on the surface of the base metal should be cleaned before welding. Nickel and its alloys have strong pore susceptibility during welding. Pay attention to operation .
Copper and its alloys have high thermal conductivity, large thermal expansion coefficient, low melting point, easy to produce cracks, pores and slag inclusions. When welding copper and its alloys, there should be a large heat input to meet the heat dissipation caused by the ultra-fast cooling rate. ; And special processes such as increasing the number of tack welds, increasing preheating and hammering between lanes.
Deq = C + 1 / 6Mn + 1 / 24Si + 1 / 5Cr + 1 / 4Mo + 1 / 15Ni
(This estimation method is suitable for low, medium and high carbon steel and low alloy steel materials)
Carbon equivalent(%) | Pre-heat temperature | Carbon equivalent(%) | Pre-heat temperature |
0.40 | 100℃以上 | 0.70 | 250℃以上 |
0.50 | 150℃以上 | 0.80 | 300℃以上 |
0.60 | 200℃以上 |
The surfacing effect, such as the hardness, wear resistance and heat resistance of the surfacing layer, is related to the operation of the welding current and the length of the arc; if the current is large and the arc is long, the alloy elements are easy to burn; Alloying element transition is favorable.
Some surfacing metals can be obtained with different hardnesses by different heat treatment methods. The hardness and chemical composition of the surfacing metal generally refers to the surfacing metal of more than three layers.
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