Introduction of hard-faced wear-resistant welding materials—FLUX CORED WIRE
1.Suggestions for welding material selection：
AWS has relevant specifications for hard-faced welding materials, such as A5.13 hard-faced covered metal arc welding, A5.21 hard-faced bare welding wire and welding rod, to define materials. However, in general practical application, welding materials rarely define corresponding international specification class numbers. Therefore, in the selection of welding materials, the content of dissolved gold composition, hardness value and application occasions recommended by manufacturers are used as materials.
This kind of material attaches great importance to the design of welding procedure, that is, what kind of welding material to use, preheating temperature, inter-track temperature, number of welding layers, whether to do post-heating, whether to do post-heat treatment, whether there is a transition layer and other important factors will determine the success or failure and service life of a hard-surface welding workpiece.
①For various environments with different working attributes, the recommended hard surface welding materials are as follows:
Hard-faced welding material category
Reference wear rate
Reference hardness value (HRC)
High carbon-high chromium, high special alloys (W, Nb, V, Co, etc.)
0.05 ~ 0.2
50 ~ 75
Medium friction + medium impact
Semi-Austenite, Austenite + Martensite, Martensite, Pearlite.
0.2 ~ 8.0
20 ~ 60
Austenite, high manganese steel, medium carbon low alloy steel.
6.0 ~ 20.0
5 ~ 55
②According to the classification of each hard surface welding material according to the organization type, the recommended application occasions are as follows：
Reference hardness (HRC)
Submerged arc welding material
Pearlite iron system
Couplers for gears, shafts, rolls, rolling mills, automatic coupling machines for vehicles, foot peripheral fittings of bulldozers and track head surfaces, etc.
Artensite iron series
Rollers or sprockets of bulldozers, idlers or track shoes, digging edges, rollers, bucket end edges, mixing blades, cutting tools and shells of dredgers, etc.
High manganese Austenite series
Blade or roller of crusher, hammer of crusher, claw of excavator and track frog
High carbon-high chromium system
Coal pulverizer, coal pulverizer rotor, sand pump shell and pump blade, ghost tooth, receiving tooth, blast furnace cover, grinder, etc.
Tungsten carbide system
Blades of bulldozers, lining tools, relieving teeth, cutting tools, concrete cutters and earth drills, etc.
Cobalt-chromium-tungsten alloy system
Bushing of high-pressure pump, moving wheel sleeve, sliding surface of high-pressure valve, turbine blade and various cutters, cutting edge for paper industry, valve seat ring of internal combustion engine, high-temperature and high-pressure valve, injection eye mold, etc.
2.Key points of welding operation：
(1)Welding wire storage management：
Recommendations for the same type of carbon steel coated welding wire.
(2)Precautions for welding：
①The hard breaded welding wire can be divided into welding slag type and metal type welding wire according to whether there is welding slag. If there is no shielding gas, it can be divided into gas shielded or self-shielded welding wire.
②Metal type flux-coated welding wires are mostly hard-surfaced materials with higher alloy content. This product has lower smoke and dust, higher slag spray, and poorer handling than slag-type flux-coated welding wires.
③The wire diameter of the gas shielded hard bread welding wire is mostly designed to be 1.2~1.6mm, and the wire diameter of the self-shielding coated welding wire is mostly designed to be 1.6~2.8mm; the self-shielding hard surface welding wire is for special applications The welding consumables developed by the demand for large fillers are worse than gas shielded welding wires in terms of slag spray volume, smoke volume and controllability.
④Pay attention to the matching of current and voltage to avoid excessive penetration of the bottom channel and cause excessive dilution rate.