Background technology
Flux-cored wire generally is divided into acidity, alkalescence, metal powder type and four kinds of fundamental types of self-shield type.Wherein solder wire with acidity core mainly is to carry out slag making with rutile, alumino-silicate, belongs to TiO
2-SiO
2Slag system. its welding technological properties excellence, the good fluidity of molten slag, solidification temperature range is very little, and the characteristic of " having short slag " is applicable to all-position welding.Owing to contain a large amount of rutile in the medicinal powder of solder wire with acidity core, alumino-silicate or other acidic oxide can make arc stability improve, make the electric arc softness, simultaneously, the interfacial tension of liquid metal and molten slag is reduced, impel the molten drop particle to diminish, easily form spray transfer.But the low-temperature impact toughness that a very big problem of its existence is exactly a weld metal is relatively poor, thereby has limited its application aspect the important structure welding.For this reason, people develop the lime-titania type flux-cored wire again, promptly add the basic anhydride of volume in medicinal powder, improve the basicity of molten slag, make the low-temperature impact toughness of weld metal obtain certain improvement like this; But the problem of Chan Shenging is because the molten slag flowability is excessive, and mode of metal transfer becomes the coarse granule transition by the fine grained transition thereupon, and welding technological properties is worsened.Thereby the range of application of lime-titania type flux-cored wire also is subjected to certain limitation.
At present, the characteristics of existing solder wire with acidity core are that welding technological properties is good, but low-temperature impact toughness is relatively poor, its ballistic work standard value Akv 〉=27J (20 ℃), and diffusible hydrogen content is generally 2~14ml/100g.
Along with industrial equipment to high strength, high tenacity and the development of ultralow hydrogen, press for that a kind of welding procedure is good, high tenacity, solder wire with acidity core that hydrogen content is low, but had not yet to see this type of product technology.
Summary of the invention
The inventor is by a large amount of research and test, prepared a kind of low hydrogen, high toughness solder wire with acidity core that welding procedure is good and have high tenacity, low hydrogen content characteristics.
The object of the invention is to provide a kind of low hydrogen, high toughness solder wire with acidity core.
Low hydrogen, high toughness solder wire with acidity core of the present invention, crust and the medicine core done by the SPCC-SD steel band constitute, and the component of medicine core comprises: 25-40%TiO
2, 2-13%SiO
2, l-4%MgO, 1-4% fluoride, 16-23% silicomangan, l-3% almag, 3-8% metallic nickel, 19-45% metal iron powder.
The component of medicine core is preferred: 25-40%TiO
2, 3-8%SiO
2, 1-2%MgO, l-3% fluoride, 16-20% silicomangan, 1-3% almag, 3-8% metallic nickel, 19-45% metal iron powder.
The component of medicine core is more preferably: 25%TiO
2, 6%SiO
2, 1.5%MgO, 1.5% fluoride, 16% silicomangan, 2% almag, 5% metallic nickel, 43% metal iron powder.
Flux-cored wire of the present invention does not have specific (special) requirements in the preparation, adopts the interior general manufacturing process of industry to realize.
The present invention has reduced the hydrogen content of deposited metal, and is improving the mechanical property of welding wire, particularly guarantees to have good welding technological properties the weld metal low-temperature impact toughness time.
Operation principle of the present invention:
As the important component that the medicine core is formed, TiO
2Main effect be stabilising arc, slag making, adjust the slag physical property, improve appearance of weld and minimizing is splashed.If content is low excessively, then be difficult for forming short slag, it is unfavorable that opposition, transverse presentation are put weldering; If content is too high, then obviously influence comprehensive mechanical property.See Table 1.
Table 1
Component | Add percentage≤20% | Add percentage 〉=43% |
TiO
2 | Slag is topped incomplete, drops down under the vertical position welding degradation, molten iron. | Cold impact value is on the low side. |
Component | Add percentage 〉=15% |
SiO
2 | Moulding is not attractive in appearance, and cold impact value is lower. |
SiO
2It is main acidic oxide, the effect that reduces slag basicity is arranged, too high when the acidic oxide addition, the content of oxygen is also often higher in the weld seam, and welding seam toughness at this moment particularly low-temperature flexibility will obviously descend, but it can reduce the fusing point of slag, increase the activity of slag, improve the flowability of slag, can also reduce the slag surface tension, reduce the adhesion between slag and liquid metal, improve deslag performance.But too high levels, the shaping variation.
MgO is the basic anhydride that add for the basicity of adjusting slag, and the effect that improves deposited metal impact flexibility is arranged, and the higher viscosity that improves slag of its fusing point.But adding excessive meeting degenerates appearance of weld.
Silicomangan uses as deoxidier and alloying constituent.
The adding of almag mainly is to carry out deoxidation and improve burn-off rate.
Metallic nickel is the alloying element, can improve low-temperature flexibility and intensity.
Characteristics of the present invention and advantage are:
1, can comprise the all-position welding of downward welding in the vertical position and in each position welding all keeps arc stability, and in use spatter is minimum, appearance of weld is attractive in appearance.
2, has good welding technological properties.Guarantee that weld seam has high strength, high tenacity, low (the glycerine method mean value 1.32ml/100g of diffusible hydrogen content; Mercury process mean value 6.7ml/100g).
3, reduced the deposited metal diffusible hydrogen content.
4, the mechanical property of welding wire has had raising, particularly weld metal low-temperature impact toughness and cracking resistance.
5, can satisfy the welding requirements of the structure that low-temperature flexibility is had relatively high expectations.