JP5236158B2 - Ferritic stainless steel welding wire and manufacturing method thereof - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a ferritic stainless steel welding wire used for gas shielded arc welding and the like and a method for manufacturing the same, and more particularly to a ferritic stainless steel welding wire used for welding an automobile exhaust system and a method for manufacturing the same. It is.

  As a wire used for gas shielded arc welding or the like, a wire using ferritic stainless steel is known. Such a ferritic stainless steel is less expensive than an austenitic stainless steel and has a low thermal expansion coefficient, so that it does not easily cause thermal fatigue. Moreover, the crack resistance in a chloride environment is also high. However, if ferritic stainless steel is welded, the base material heat-affected zone may contain a small amount of martensite due to components such as Cr, but the majority remains in the ferrite structure. Thus, since ferritic stainless steel hardly transforms, when the heat input becomes large, the crystal of the weld metal becomes coarse and brittle.

  The same applies to weld metal welded with the same or similar welding wire (metal alloy welding material) as the base material of ferritic stainless steel. The tensile strength is low, the toughness by the Charpy impact test is low, and the bendability is also low. Further, the crack resistance is also lowered. Tensile strength can be improved by heat treatment after welding, but even after heat treatment, the toughness and bendability by the Charpy impact test remain low.

  Therefore, Japanese Patent Application Laid-Open No. 2004-42116 (Patent Document 1), Japanese Patent Application Laid-Open No. 2004-141934 (Patent Document 2), Japanese Patent No. 2500008 (Patent Document 3), and Japanese Patent Application Laid-Open No. 2005-971 (Patent Document). As shown in 4), a ferritic stainless steel welding wire has been proposed in which a small amount of Al, Ti, or the like is added to prevent the weld metal crystals from coarsening and crack resistance is improved.

In this specification, “high crack resistance” means that the bead (weld metal) is difficult to crack after welding, and “low crack resistance” means that the weld metal is cracked after welding. Means easy. In addition, “high bendability” means that the weld metal is difficult to crack even if the weld metal is bent, and low bendability means that the weld metal is easily cracked when the weld metal is bent. . Further, “high corrosion resistance” means that the weld metal is hardly corroded, and “low corrosion resistance” means that the weld metal is easily corroded. Furthermore, “high oxidation resistance” means that the weld metal is hardly oxidized, and “low oxidation resistance” means that the weld metal is easily oxidized.
JP 2004-42116 A JP 2004-141934 A Japanese Patent No. 2500008 JP 2005-971 A

  The following points are required for ferritic stainless steel welding wires used for automobile exhaust system welding.

  (1) The wire can be prevented from being disconnected and can be manufactured relatively easily.

  (2) The weld metal has high crack resistance.

  (3) The crystal grain size of the weld metal (the metal in the welded portion where the base material and the weld material after welding are mixed) is large and fine.

  (4) The bendability of the weld metal is high.

  (5) The tensile strength of the weld metal up to a high temperature is not less than the standard (base material).

  (6) The weld metal has high corrosion resistance.

  (7) The oxidation resistance of the weld metal is high.

  However, the conventional ferritic stainless steel welding wire has a limit to satisfy all these conditions.

  The welding of an automobile exhaust system is usually performed efficiently by an automatic device such as a robot. Therefore, it is required to perform stable welding with a smooth supply using a wire having an appropriate hardness and a uniform and smooth surface.

  An object of the present invention is to provide a ferritic stainless steel welding wire capable of improving crack resistance, bendability, tensile strength up to high temperature, corrosion resistance, and oxidation resistance by reducing crystal grains.

  Another object of the present invention is to provide a ferritic stainless steel welding wire that can prevent wire breakage and can be manufactured relatively easily in addition to the above object, and a method for manufacturing the same.

  The ferritic stainless steel welding wire of the present invention has C: 0.03 mass% or less, Si: 3 mass% or less, Mn: 3 mass% or less, Ni: 2 mass% or less, Cr: 11-20 mass%, Mo : 3 mass% or less, Co: 1 mass% or less, Cu: 2 mass% or less, Al: 0.02-2.0 mass%, Ti: 0.2-1.0 mass%, O: 0.02 mass % Or less, N: 0.04 mass% or less, at least one of Nb and Ta: (8 times the mass% of the total of C and N) to 1.0 mass%, with the balance being Fe and inevitable impurities .

In the ferritic stainless steel welding wire of the present invention, the crystal size of the weld metal can be increased to refine the crystal, thereby improving crack resistance, bendability, tensile strength up to high temperature, corrosion resistance, and oxidation resistance. The grain size is a grain size number (G) obtained in accordance with the comparison method of ferrite grain size test method 6.1 of steel of JIS-G-0552. This particle size number (G) is an index represented by m = 8 × 2 ^G, where m is the number of crystals per 1 mm ² cross-sectional area. In general, a weld metal is a so-called cast structure in which a part of a welding wire and a base material (material to be welded) is melted and solidified in a short time by a heat source such as an arc, and the crystal grain size is adjusted by the composition of the wire. The

  In particular, in the present invention, by adding appropriate amounts of Al and Ti, crystals can be effectively made finer than conventional wires. Moreover, corrosion resistance can be improved by adding an appropriate amount of at least one of Nb and Ta.

  Below, the effect | action of each composition and the reason for limitation of content are demonstrated.

  C is an austenite generating element and can increase the strength of the weld metal. However, if the content exceeds 0.03% by mass, the corrosion resistance of the weld metal is lowered, martensite is formed in the cooling process after welding, and weld cracks are likely to occur.

  Si and Mn have a deoxidizing action. However, when the Si content is increased, the toughness of the weld metal is lowered and the ductility is deteriorated. Moreover, when content of Mn is raised, workability will fall and the oxidation resistance of a weld metal will fall. Accordingly, the content is 3% by mass or less.

  Ni is an austenite generating element and improves the ductility, toughness and bendability of the weld metal. However, when the content is increased, the crack resistance of the weld metal decreases. Therefore, the content is set to 2% by mass or less.

  Cr is a ferrite-forming element and improves high-temperature strength, corrosion resistance, and oxidation resistance. However, if it is less than 11% by mass, a sufficient effect cannot be obtained. Moreover, when it exceeds 20 mass%, it will become hard to manufacture.

  Mo is a ferrite-forming element and enhances high temperature strength and corrosion resistance. However, if the content exceeds 3% by mass, the toughness and bendability of the weld metal deteriorate.

  Co enhances high-temperature characteristics such as tensile strength and oxidation resistance at high temperatures, but considering the cost, the content is set to 1% by mass or less.

  Cu improves the hot metal flow of the weld metal and forms a good bead. Moreover, although addition with a small amount improves crack resistance, toughness, and bendability, when the content exceeds 2% by mass, the content decreases.

  Al and Ti are deoxidizers, Al forms N, O and nitrides and oxides in the welding process, Ti forms N, C and nitrides and oxides, which serve as nuclei, etc. A fine-grained structure of axial crystals is obtained. Further, since Ti carbide is more easily formed than Cr carbide, it is possible to prevent the corrosion resistance from being lowered due to the decrease in Cr. If the content of Al and Ti is less than 0.02% by mass and 0.2% by mass, these effects cannot be obtained. Moreover, when it exceeds 2.0 mass% and 1.0 mass%, it will become easy to produce a disconnection at the time of manufacture of a wire. Further, these nitrides and oxides are slagted after welding, and the appearance of the beads is deteriorated. Therefore, the Al content is set to 0.02 to 2.0 mass%, and the Ti content is set to 0.2 to 1.0 mass%.

  O is included in a certain amount in the wire manufacturing process. However, when the content is increased, excessive oxide is formed, and toughness and bendability are lowered. Therefore, the content of O needs to be suppressed to 0.02% by mass or less.

  N is an austenite generating element. As described above, Al, Ti and nitride are produced, and these become nuclei in the cooling process after the weld metal is solidified, and an equiaxed crystal structure is obtained. However, if the content exceeds 0.04% by mass, the crack resistance, toughness, and bendability of the weld metal deteriorate.

Nb and Ta are group V elements of the periodic table and have similar properties. These are all carbonitride-forming elements and have the effect of suppressing the precipitation of Cr carbides that reduce the corrosion resistance. This effect cannot be obtained if at least one of Nb and Ta is less than 8 times the total mass% of C and N. For example, when C is 0.01% by mass and N is 0.005% by mass, the effect cannot be obtained if it is less than (0.01% by mass + 0.005) × 8 = 0.12% by mass. On the other hand, if the content of at least one of Nb and Ta exceeds 1.0% by mass, the crack resistance, toughness and bendability of the weld metal are lowered, and breakage is likely to occur during the production of the wire.

  In the wire of the present invention, P: 0.04 mass% or less, S: 0.02 mass% or less, V: 0.5 mass% or less, W: 0.5 mass% or less, Zr: 0.02 mass% or less B: 0.02% by mass or less, Ca: 0.005% by mass or less, Mg: 0.005% by mass or less can further be contained.

  When the content of P and S is high, the crack resistance and toughness of the weld metal are lowered, and the bendability is lowered. When P and S are contained as impurities, it is necessary that the P content is 0.04 mass% or less and the S content is 0.02 mass% or less. V is a carbide-forming element and has the effect of suppressing the precipitation of Cr carbide that lowers the corrosion resistance. However, if it exceeds 0.5 mass%, the welding arc becomes unstable. W increases the high-temperature strength and corrosion resistance, but if it exceeds 0.5% by mass, the toughness and bendability of the weld metal decrease. Zr, B, Ca, and Mg improve the deoxidation action and metal workability, but if they exceed 0.02 mass%, 0.02 mass%, 0.005 mass%, and 0.005 mass%, the welding arc It becomes unstable.

  As described above, the wire of the present invention satisfies the points required for welding of an automobile exhaust system, and therefore, when used as a welding wire for an automobile exhaust system, a high effect can be obtained.

  Usually, a ferritic stainless steel welding wire is manufactured by subjecting a wire to a heat treatment and then drawing to a predetermined wire diameter with a main die or the like. In this manufacturing method, it is preferable to use the wire having the above-described components and to perform heat treatment so that the crystal grain size of the wire is 3 to 10. In such a range, disconnection in the wire drawing process can be prevented. When the crystal grain size of the wire is less than 3 and the crystal becomes large, the crystal grains are coarsened, and thus disconnection occurs in the subsequent wire drawing step. Since ferritic stainless steel cannot be refined by any means other than mechanical methods such as cold rolling, it is substantially impossible to produce wires. Moreover, even if the crystal size is smaller than 10, wire breakage is likely to occur in the wire drawing process. In this case, the wire can be drawn by performing the heat treatment again, but the number of man-hours increases and the manufacture of the wire becomes complicated. The crystal grain size of the wire referred to here is the grain size number (G) obtained in accordance with the comparison method described in Section 6.1 of the ferrite grain size test method for steel of JIS-G-0552 described above. Further, the crystal grain size of the wire is not related to the crystal grain size of the weld metal described above. The crystal grain size of the wire is greatly affected by the heat treatment applied to the wire, and the crystal grain size of the weld metal is greatly influenced by the wire composition as described above.

  In order to make the crystal grain size of the wire from 3 to 10, in the case of the composition of the present invention, for example, a heat treatment may be performed by heating at 1000 ° C. ± 100 ° C. and then rapidly cooling.

  Usually, a ferritic stainless steel welding wire is often subjected to heat treatment on a wire having a wire diameter of 2 to 10 mm and then drawn to a wire diameter of 0.6 to 2 mm. In this case, as wire rods, C: 0.03% by mass or less, Si: 3% by mass or less, Mn: 3% by mass or less, Ni: 2% by mass or less, Cr: 11 to 20% by mass, Mo: 3% by mass or less Co: 1 mass% or less, Cu: 2 mass% or less, Al: 0.02 to 2.0 mass%, Ti: 0.2 to 1.0 mass%, O: 0.02 mass% or less, N: 0.04% by mass or less, at least one of Nb and Ta: (8 times the total mass% of C and N) to 1.0% by mass, and the remainder is made of Fe and inevitable impurities, and heat treatment And the crystal grain size of the wire may be 3-10. In this way, it is possible to obtain a ferritic stainless steel welding wire that can prevent disconnection in the wire drawing process and can improve crack resistance and the like.

  According to the present invention, it is possible to obtain a ferritic stainless steel welding wire capable of improving crack resistance, bendability, tensile strength up to high temperature, corrosion resistance, and oxidation resistance. In particular, since the point required for welding of an automobile exhaust system is satisfied, a high effect can be obtained when used as a welding wire for an automobile exhaust system.

In order to confirm the effect of the present invention, solid wires made of ferritic stainless steel welding wires of various compositions were made and tested. First, wire materials having a wire diameter of 5.1 to 5.5 mm were prepared using the compositions of Examples 1 to 10 and Comparative Examples 1 to 25 of the present invention as shown in Table 1. In addition, in at least one column (Nb, Ta) of Nb and Ta, a lower limit value (8 times the total mass% of C and N) is also described for reference.

Next, two heat treatments 1 and 2 having different conditions were applied to each wire. Heat treatment 1 is a heat treatment that is rapidly cooled after heating at 1000 ° C. ± 100 ° C., and heat treatment 2 is a heat treatment that is heated at 800 ° C. ± 100 ° C. and then slowly cooled. And the crystal grain size after these heat processing and the disconnection condition at the time of manufacturing each wire rod to a wire diameter of 1.2 mm with 10-12 dies after heat processing were investigated. Table 2 shows the results. In JIS-G-0552, the particle size number is defined in the range of -3 to 10, but in this example, it is described beyond the range of -3 to 10.

  In the determination of the disconnection state in Table 2, when the crystal grain size of the wire exceeds 3, A: No disconnection, ○: Disconnection once, Δ: Disconnection twice or more, ×: It was assumed that the disconnection occurred frequently. In addition, when the crystal grain size of the wire is 3 or less, ◎: one that is not broken, ○: one that is broken, ×: a wire that is broken due to coarse crystal grains, and cannot be drawn thereafter did.

  From Table 2, when the wire materials of Examples 1 to 10 of the present invention are heated at 1000 ° C. ± 100 ° C. and then rapidly cooled to make the crystal grain size 3 to 10, wire breakage in the wire drawing process can be prevented. I know you can.

Next, using the wires having the compositions of Examples 1 to 10 and Comparative Examples 1 to 25 subjected to heat treatment 2, crack resistance test, measurement of crystal size of weld metal, bending test, tensile test, corrosion resistance test, oxidation resistance A sex test was performed. Table 3 shows the measurement results.

The crack resistance test was conducted in accordance with the T-type weld crack test method of JIS-Z-3153. Specifically, as shown in FIG. 1, two stainless steel plates 1 of SUS430 having a thickness of 19 mm, a length of 150 mm, and a width of 80 mm are arranged in a T shape with a gap G of 1 mm, and a test bead B1. Gas shield arc welding was performed with each wire across the two stainless steel plates 1 so as to form the constraining bead B2. Specifically, first, a confining bead B2 was formed at a welding speed of 30 cm / min by flowing a shielding gas of Ar + 20% CO ₂ at a flow rate of 20 l / min with a current of 230 A and a voltage of 25 V. Next, a test bead B1 was formed at two welding speeds of 60 cm / min and 80 cm / min by flowing a shielding gas of Ar + 20% CO ₂ at a flow rate of 20 l / min with a current of 230 A and a voltage of 25 V. And it determined by calculating | requiring the crack rate [(crack length / bead length) x100] of the surface of test bead B1 except a crater part. Judgment was made as follows: ◯: cracking rate 0%, Δ: cracking rate 0% above and below 30%, x: cracking rate 30% or more.

  From Table 3, when the wires of Examples 1 to 10 were used, the weld metal was compared with the case of using the wires of Comparative Examples 4, 5, 7, 9 to 11, 17, 18, 20, 21, 23, 25. It can be seen that the cracking rate can be lowered.

  The crystal size of the weld metal was determined in accordance with the JIS-G-0552 steel ferrite grain size measurement test method. A grain size of 3 or more is recognized as a fine grain. In addition, the crystal grain size of the weld metal here is not related to the crystal grain size of the wire shown in Table 2. The crystal grain size of the weld metal is greatly influenced by the composition of the wire and its value is determined, and the crystal grain size of the wire is largely influenced by the heat treatment applied to the wire and its value is determined.

  From Table 3, when the wires of Examples 1 to 10 were used, the crystal grains were all fine grains of 3 or more, whereas the wires of Comparative Examples 1 to 5, 7 to 11, and 14 to 25 were used. When used, it can be seen that the grain size is below 3.

The bending test was performed using two SUS429 Mod., 1.5 mm thick, 150 mm long, and 50 mm wide. As shown in FIG. 2, the two stainless steel plates 2 are arranged such that the end portions in the width direction are overlapped as shown in FIG. 2, and the bead B3 is formed with a torch angle θ of 10 ° as shown in FIG. Gas shield arc welding was performed with each wire across the wire. Specifically, Ar + 20% CO ₂ shielding gas was flowed at a flow rate of 20 l / min with a current of 150 A and a voltage of 24 V, and the welding speed was 80 cm / min. Then, as shown in FIG. 4, the two beads B3 are positioned on the two cylinder C sides with a diameter of 32 mm arranged at a pitch of 100 mm, and both ends in the length direction are in contact with the two cylinders C. A stainless steel plate 2 was arranged. Then, two welded stainless steel plates 2 are pushed in with three push-in amounts of 20 mm, 40 mm, and 60 mm using a press P whose tip is curved with a diameter of 13.5 mm from a direction perpendicular to the longitudinal direction of the bead B3. Bent in. And the surface crack of bead B3 was investigated and judged by the dye penetration test. Judgment: ○: no crack, Δ: 2 or less cracks having a length of 1 mm or less, and x: 3 or more cracks having a length of 1 mm or more.

  From Table 3, when the wire of Examples 1-10 is used, the crack generation by bending can be made low compared with the case where the wire of Comparative Examples 1, 4, 5, 7, 8, 11, 14-25 is used (bending) Can be improved).

As shown in FIG. 5, the tensile test, the corrosion resistance test, and the oxidation resistance test were performed using two SUS429 Mod. The stainless steel plates 3 were arranged so that the end portions in the width direction were different by 10 mm, and gas shield arc welding was performed across the two stainless steel plates 3 so as to form the beads B4. Specifically, similarly to the above-described bending test, Ar + 20% CO ₂ shielding gas was flowed at a flow rate of 20 l / min with a current of 150 A and a voltage of 24 V, and the welding speed was 80 cm / min. And the two stainless steel plates 3 were equally divided into 5 so as to form the cut pieces 4 to 8, and the three cut pieces 5 to 7 at the center were used for a tensile test, a corrosion resistance test, and an oxidation resistance test. The cut pieces 4 and 8 at both ends were discarded.

  In the tensile test, as shown in FIGS. 6A and 6B, the test piece 9 was formed by forming a constriction so that the dimension of the central portion of the cut piece 5 was 40 mm in length and 40 mm in width. The test piece 9 was pulled from both ends at room temperature (RT), 700 ° C., and 900 ° C., and the force per unit area (Mpa) when the test piece 9 was cut was measured. In the test pieces using the wires of Comparative Examples 6, 14, 15 and 23 marked with an asterisk in Table 3, the weld metal (bead B4) portion was cut from the weld heat affected zone, and in the other test pieces, the base metal was used. 3a was cut. Note that the cross-sectional area of the cut portion was determined from the cross-sectional area of the base material 3a, whether the weld metal portion was cut or the base material 3a was cut.

  From Table 3, when the wires of Examples 1 to 10 were used, all were cut with the base material 3a, whereas when the wires of Comparative Examples 6, 14, 15, and 23 were used, the weld metal (beads) It can be seen that it is cut at B4).

  The corrosion resistance test was conducted according to the oxalic acid etching test method for stainless steel of JIS-G-0571. Specifically, the cut piece 6 was masked on a portion (base material) other than the weld metal (bead B4), immersed in a 10% oxalic acid solution, and energized at a constant current density for determination. The judgment was made as follows: ◯: no groove-like structure was observed, Δ: groove-like structure was partially recognized, and x: groove-like structure was recognized at all crystal grain boundaries.

  From Table 3, when the wires of Examples 1 to 10 are used, the corrosion resistance can be increased as compared with the case of using the wires of Comparative Examples 1, 2, 6 to 8, 11 to 16, 18, 19, 22, and 24. I understand.

In the oxidation resistance test, as shown in FIGS. 7A and 7B, the central portion of the cut piece 7 was cut into a length of 40 mm and a width of 30 mm to form a test piece 11. And the test piece 11 was heated at 900 degreeC for 48 hours in air | atmosphere, and the increase (g / cm < ² >) by the oxidation per unit area was measured. An oxidation increase of 1 g / cm ² or less is good.

From Table 3, when the wires of Examples 1 to 10 are used, all are good and the oxidation resistance is high, whereas when the wires of Comparative Examples 6, 14, 15, and 23 are used, the amount of increase in oxidation is increased. It can be seen that the oxidation resistance is reduced by exceeding 1 g / cm ² .

  As described above, from Table 3 as a whole, when the wires of Examples 1 to 10 of the present invention were used, the crystal grain size of the weld metal was increased to make the crystal finer, crack resistance, bendability, and high temperature. It can be seen that the tensile strength, corrosion resistance, and oxidation resistance can be improved.

Table 4 shows the results of the crack resistance test, the measurement of the grain size of the weld metal, the bending test, the tensile test, the corrosion resistance test, and the oxidation resistance test when the wires having the compositions of Examples 1 to 10 subjected to the heat treatment 1 were used. Is shown.

  It can be seen from Table 4 that even when heat treatment 1 is applied, the wires having the compositions of Examples 1 to 10 can obtain the same performance as in Table 3.

It is a side view of the welded state of the stainless steel plate used for a crack resistance test. It is a perspective view of the state by which the stainless steel plate used for a bending test was welded. It is a figure of the aspect which welds the stainless steel plate used for a bending test. It is a figure of the aspect which performs a bending test to the welded stainless steel plate. It is a top view of the welded state of the stainless steel plate used for a tensile test, a corrosion resistance test, and an oxidation resistance test. (A) And ( B ) is the top view and side view of a test piece used for a tension test. (A) And ( B ) is the top view and side view of a test piece used for an oxidation resistance test.

Explanation of symbols

1, 2, 3 Stainless steel plate 4-8 Cut pieces

Claims (6)

C: 0.03 mass% or less (not including 0 mass%) , Si: 3 mass% or less (not including 0 mass%) , Mn: 3 mass% or less (not including 0 mass%) , Ni: 2 % By mass (not including 0% by mass) , Cr: 11 to 20% by mass, Mo: 3% by mass or less (not including 0% by mass) , Co: 1% by mass or less (not including 0% by mass) , Cu: 2 mass% or less (excluding 0 mass%) , Al: 0.02-2.0 mass%, Ti: 0.2-1.0 mass%, O: 0.02 mass% or less (0 mass) %) , N: 0.04 mass% or less (excluding 0 mass%) , at least one of Nb and Ta: (8 times the total mass% of C and N) to 1. A ferritic stainless steel welding wire comprising 0% by mass and the balance being Fe and inevitable impurities. P: 0.04% by mass or less (not including 0% by mass) , S: 0.02% by mass or less (not including 0% by mass) , V: 0.5% by mass or less (not including 0% by mass) , W: 0.5% by mass or less (excluding 0% by mass) , Zr: 0.02% by mass or less (not including 0% by mass) , B: 0.02% by mass or less (excluding 0% by mass ) ) , Ca: 0.005 mass% or less (excluding 0 mass%) , Mg: 0.005 mass% or less (not including 0 mass%) , further containing at least one. Ferritic stainless steel welding wire. In the method of manufacturing a ferritic stainless steel welding wire that is subjected to heat treatment on the wire and then drawn,
As said wire, C: 0.03 mass% or less (not including 0 mass%) , Si: 3 mass% or less (not including 0 mass%) , Mn: 3 mass% or less (not including 0 mass%) Ni: 2% by mass or less (excluding 0% by mass) , Cr: 11-20% by mass, Mo: 3% by mass or less (not including 0% by mass) , Co: 1% by mass or less (0% by mass ) includes not), Cu: 2 mass% or less (not including 0 mass%), Al: 0.02 to 2.0 mass%, Ti: 0.2 to 1.0 wt%, O: 0.02 wt% Or less (excluding 0% by mass) , N: 0.04% by mass or less (not including 0% by mass) , at least one of Nb and Ta: (8 times the total mass% of the C and the N) ) -1.0% by mass and the balance is made of Fe and inevitable impurities,
A method for producing a ferritic stainless steel welding wire, wherein the heat treatment is performed so that the crystal grain size of the wire is 3 to 10. As said wire, P: 0.04 mass% or less (not including 0 mass%) , S: 0.02 mass% or less (not including 0 mass%) , V: 0.5 mass% or less (0 mass%) ) , W: 0.5 mass% or less (including 0 mass%) , Zr: 0.02 mass% or less (including 0 mass%) , B: 0.02 mass% or less ( including 0 mass%) ) , Ca: 0.005 mass% or less (including 0 mass%) , Mg: 0.005 mass% or less (including 0 mass%) , and using a wire further containing at least one The manufacturing method of the ferritic stainless steel welding wire of Claim 3.   5. The method for producing a ferritic stainless steel welding wire according to claim 3, wherein the heat treatment is rapid cooling after heating at 1000 ° C. ± 100 ° C. 5. In the method for producing a ferritic stainless steel welding wire, heat treatment is performed on a wire having a wire diameter of 2 to 10 mm, and then the wire is drawn to a wire diameter of 0.6 to 2 mm.
As said wire, C: 0.03 mass% or less (not including 0 mass%) , Si: 3 mass% or less (not including 0 mass%) , Mn: 3 mass% or less (not including 0 mass%) Ni: 2% by mass or less (excluding 0% by mass) , Cr: 11-20% by mass, Mo: 3% by mass or less (not including 0% by mass) , Co: 1% by mass or less (0% by mass ) includes not), Cu: 2 mass% or less (not including 0 mass%), Al: 0.02 to 2.0 mass%, Ti: 0.2 to 1.0 wt%, O: 0.02 wt% Or less (excluding 0% by mass) , N: 0.04% by mass or less (not including 0% by mass) , at least one of Nb and Ta: (8 times the total mass% of the C and the N) ) -1.0% by mass and the balance is made of Fe and inevitable impurities,
A method for producing a ferritic stainless steel welding wire, wherein the heat treatment is performed so that the crystal grain size of the wire is 3 to 10.

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