JPS6336995A - Flux cored wire for welding 'inconel(r)' alloy - Google Patents

Abstract

PURPOSE:To improve welding quality and welding workability by incorporating respectively specific weight % of titanium oxide, carbonate, fluoride, etc. into a flux component and limiting the flux to a prescribed % range of the total weight of a wire. CONSTITUTION:2.5-15% 1 Or >=2 kinds of titanium oxide and titanate, by the total weight of the wire, 0.2-7% carbonate, 0.5-5% SiO2, Al2O3, etc., 0.05-2% fluoride, 0.1-2% Ti, Al, and 1-7% metallic powder are incorporated into the flux component and the amt. of the flux is limited to 10-30% of the total weight of the wire. The titanium oxide component improves the removability of slag and both the carbonate and fluoride prevent the generation of blowholes. The Ti and Al acts as deoxidizing and denitrifying agents. Both the welding quality and workability of welding are, therefore, improved by the above-mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a 7-lux cored wire for automatic and semi-automatic welding of Inconel alloys with excellent welding properties.

[Conventional technology]

Conventionally, in automatic or semi-automatic welding of Inconel alloy, MIG welding using solid wire has been common. In addition, high nickel alloy flux-cored wire is
JP-A-58-6795 and JP-A-58-132
Although it is shown in Publication No. 393, in both cases pure Ni is used in the outer skin.
There are no known ones that use Inconel alloy for the outer skin.

[Problem that the invention seeks to solve]

MIG welding with solid wire produces a hard oxide film on the surface of the bead, and when welding in piles, the oxide film gets rolled up, causing blowholes, poor fusion, weld cracks, etc. For this purpose, it is necessary to remove the oxide film, which requires a great deal of effort.

Furthermore, since Inconel alloy has poor thermal conductivity compared to mild steel, it is used only for downward welding and is not suitable for vertical or horizontal welding. TIG welding and shielded arc welding, which are suitable for vertical and horizontal welding, are inefficient, and especially in the case of shielded arc welding, the quality of the weld varies widely depending on the skill level of the welder. The flux-cored wire disclosed in JP-A-58-6795 is for submerged arc welding, requires an additional 7 lux for submerged arc welding, and is designed for downward welding only. Also, JP-A-58
The 7-lux-cored wire of Publication No. 132393 is also for downward welding, and since the outer sheath is Ni, for example, the welding start part melts first from the outer sheath, so the alloying elements in the flux solidify before they are sufficiently melted. The object of the present invention is to provide a flux-cored wire for Inconel alloy welding that allows for efficient welding in both horizontal and vertical positions and provides a uniform and sound weld. shall be.

[Failure to solve the problem]

The present invention is a 7-lux cored wire having an outer sheath made of an Inconel alloy, and the flux is 10 to 30% of the total weight of the wire. The flux component is the weight ratio of the entire wire, dispersible tita/.

and one or more selected from titanates z5
~15%, one type of carbonate or 2t1 or more 0°2~7%
, 5t (h + 0.5-5% of one or more selected from Altos and their compounds, 1% of fluoride
Species or two or more types 0.05 to 2%% Ti and one or two types selected from Ti and 0.1 to 2%, T%, At, one or more metal powders 1 to 7 This is a 75x wire for welding Inconel alloys, which is characterized by its strength.

What is Inconel alloy? %Nt 50% by weight or more, C[10~
Nt-C containing 25% by weight, Mo 0-18% by weight
r-based alloy, Ni-Cr-Fa-based alloy and Ni
-Cr-Mo alloy.

Inconel alloy was used for the outer sheath of the flux-cored wire in order not to impair the uniformity of the weld metal.

The 7 lux contained in the wire is 10 to 30% of the total weight of the wire, and if it is less than 10%, the slag will not be able to sufficiently cover the molten metal during welding, resulting in oxidation of the weld metal and protrusion. , causing defects such as poor fusion and weld cracks. Moreover, if it exceeds 30 inches, there will be too much slag, causing problems such as covering the molten pool, and causing defects such as poor fusion and slag entrainment.

Titanium Turmeric Oxide and Titanium #! One or more types of ρ are used in a weight ratio of 25 to 15% of the wire, but if it is less than 25 inches, the peeling of the slag after solidification will be poor, and if it exceeds 15%, the amount of slag will increase, and it will not work in the 4IK groove. Deteriorates welding workability. Examples of titanate include 1, e.g. CaTiOs.
+ BaTiOs e Na*Tiσ1LizTiO
There is also KgTiO Hatake et al.

The weight ratio of one or more carbonates to the wire is 0.2.
~7% is used, but these improve the fluidity of the slag and improve the compatibility between the weld metal and the base metal, resulting in a good bead shape. In addition, during welding within a groove, it prevents slag from covering the molten pool and makes the slag brittle so that it can be easily removed. Furthermore, the carbon tR gas decomposed by the welding heat blocks the atmosphere, prevents oxidation of the weld metal and the generation of blowholes, and also protects the weld metal as a slag forming agent. 0,
If it is less than 2%, no effect can be expected, and if it exceeds 7%, not only will spatter occur frequently, but also carbon in the weld metal will increase, deteriorating corrosion resistance and toughness. As the carbonate, for example, LizCOs + Bacon + CaC0m
*Na5CO@r 5rCO1e MnC0a r
There are MgCO5 etc.

And preferably Li 2 Cow and Na! cO
061 to 3% by weight of wire of one or two types of s,
Use 0.1-4% of other carbonates.

5i (h h A1.*Om or one or more selected from these compounds at a wire weight ratio of 0.5
~5% is used, and they not only stabilize the arc together with assimilated titanium and titanate, adjust the viscosity of the slag and improve the flow of the metal, but also give gloss to the surface of the weld metal.

If it is less than 0.5%, no effect can be expected, and if it exceeds 5%, the slag will harden and it will be difficult to remove the slag, especially within the groove. Examples of compounds of 5i02 or AtzOs include mica, talc, bentonite, potassium feldspar, and the like.

TMT or 2 or more types of fluoride at wire weight ratio of 0.0
These fluorides are used at a rate of 5 to 2%, but during welding, these fluorides decompose due to welding heat during the process of wire droplets transferring to the molten pool, generating fluorine-based gas, and shielding the area near the transferring droplets and molten pool. This prevents blowholes and cracks in the weld metal. If the ratio is less than 0.05, the effect cannot be expected;
If the temperature exceeds the limit, spatter and fluorine-based gas will increase, worsening welding workability. Examples of fluorides include CaF2+
Na5klFe r KzSiFs + K2TiFg
+ BaF21 CeF2 + 2ZrF6. M
gF2r A1. There are Fa etc.

One or two selected from Tj and Al are used in an amount of 0.1 to 2% by weight of the wire. These are powerful denitrifying, denitrifying, and denitrifying agents that prevent blowholes and weld cracks. 0
．． If it is less than 1%, no effect can be expected, and if it exceeds 2%, the viscosity of the slag becomes too high, making it difficult to weld in vertical and horizontal positions, and causing bits, blowholes, etc.

The metal powder, including the aforementioned Ti and AIZ, is used in an amount of 1 to 7% by weight of the wire. Metal powders other than Ti and At are generally used to supplement oxidation consumption during welding or to add alloying elements from flux. If the total amount of metal powder is less than 1%, there will be insufficient replenishment for the oxidative consumption of alloying elements, and if it exceeds 7%, the balance with flux raw materials other than metal powder will be poor, resulting in poor welding workability. T
Examples of metal powders other than i and g include Cr + Ni
, Mo+Nb+ Mn+ Co, V, etc.

〔Effect of the invention〕

The effects of the flux shear wire for welding Inconel alloys of the present invention are as follows.

(1) By using Inconel alloy for the outer skin, there is no need to add large amounts of alloying elements from flux.
Since uniform weld metal can be obtained from the welding start part to the welding end part, a stable welded part can be obtained without defects.

(2) Excellent workability and bead shape can be obtained not only in the downward position but also in the vertical and horizontal positions.

(3) The mechanical properties of the deposited metal and weld metal are equivalent to or better than those of conventional coated arc welding rods and MIG welding.

〔Example〕

The present invention will be explained by examples. The Inconel alloy strip used as the skin had the chemical composition shown in Table 1 and had dimensions of 0.25 x 8 mm. Hl is Ni-C
It is an r -Fe-based Inconel alloy, and I (2 is Ni
-Cr-Mo based Inconel alloy. The fluxes used were four types, F1 to F4 shown in Table 2, and the blending ratio was expressed in weight t% with respect to the entire wire.

The combinations of flux and strips were as shown in Table 3, and wires W1 to W4 were manufactured to wire diameters of 1.2 mm and wires W5 to W8 were manufactured to wire diameters of 1.6 mm by cold roll forming.

Each wire was tested under the welding conditions shown in Table 4 in a downward position for the weld metal analysis test piece and the mechanical test piece, and under the welding conditions shown in Table 5 for the vertical welding test by moving a V-shaped dissimilar metal joint upward. In the horizontal overlay welding test, the base material was 5S41 (dimensions 50 mm t
Each welding was carried out under the welding conditions shown in Table 6 using 300 mm x 400 mm. The base materials for the vertical welding test were SUS 304 and Cr No steel plate with a thickness of 25 m.
m butt joint is used, the groove shape is V-shaped, the internal angle of fJ tip is 1i60', the distance between root faces is 2, and the root spacing is 2wn.
, without backing.

(1) Evaluation of the chemical composition of the weld metal is A.
WS ERNiCr-3 and AWSERNicrM
When compared with O-3 wire standards, results satisfying these standards were obtained. The chemical component analysis results are shown in Table 7, and the mechanical properties are shown in Table 8.

(2) The vertical welding test was conducted by advancing vertically.

The results are shown in Table 9, and no welding defects such as slag entrainment, poor fusion, or blowholes were observed, and the bead appearance was smooth and good. No cracks were observed in the joint bending test, showing excellent strength and elongation, and all joint tensile tests were conducted using Cr.
- Mother of Mo steel side (O fractured).

(3) The results of the lateral overlay welding test are shown in Table 10, and no welding defects such as slag entrainment, poor fusion, or blowholes were observed, the bead appearance was good, and the bending test was also satisfactory. It showed ductility.

Table 2 Mixing ratio of flux (weight 1t%) Table 3 Combination of strip and flux Table 4 Welding conditions for weld metal analysis test piece and mechanical test piece (downward position) Table 5 Welding conditions for vertical welding test

Claims (1)

[Claims] A flux-cored wire with an outer sheath of Inconel, in which the flux is 10 to 30% of the weight of the entire wire.
The components of the flux are 2.5 to 15% of one or more selected from titanium oxide and titanates, and 0.2 to 15% of one or more selected from carbonates, based on the weight ratio of the entire wire.
2 to 7%, 0.5 to 5% of one or more selected from SiO_2, Al_2O_3 and their compounds;
0.05-2% of one or more fluorides, 0.1-2% of one or two selected from Ti and Al, Ti
and one or more metal powders including Al
A flux-cored wire for welding Inconel alloy, characterized by having a flux-cored wire of 7%.