JP2013158796A - Build-up welded steel sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a build-up welding structure capable of forming a metal layer having physical property resistance on a base steel sheet accurately at a low cost.SOLUTION: A planar coating material 2 is provided, which is disposed on the surface of a base steel sheet 1, has a plurality of through-holes 3, and has a physical property resistance. The base steel sheet and the coating material are laser-welded via the through-holes. The through-holes of the coating material are sparsely arranged when its thickness is small, and densely arranged when its thickness is large.

Description

  The present invention relates to a build-up welded steel sheet for forming a metal layer of a member having physical resistance on the surface of a base steel sheet.

Conventionally, wear and corrosion due to powder and gas often occur in a portion where the powder or gas that is a fluid contacts. Although metal materials having properties corresponding to the respective materials may be used, the metal material having such properties is expensive.
As a countermeasure, it is known that a material having wear-resistant or corrosion-resistant physical characteristics is formed on the surface of the base steel plate by overlay welding.

  In the case of overlay welding, in the case of the welding method by MIG welding (Metal Inert Gas Welding), since it is a consumable electrode, a welding material having physical resistance characteristics on the surface of the base steel plate is automatically used by the feeding device. Since it is fed, it is difficult to adjust the thickness of the metal layer having physical characteristics.

As a first conventional example, a method of forming a metal layer welded by laser beam welding by disposing a thin plate-like coating material having physical resistance on the surface of a base steel plate (material to be welded) is disclosed. ing.
As an example, as shown in FIG. 8, a 30 μm SUS material covering material is disposed on a SUS material base steel plate having a thickness of 3 mm, and a semiconductor laser welding machine (output: 500 W, welding speed: 35 m / min) In the case where welding is performed at a point, there is a problem of cutting in the middle of the covering member.
This is probably because the covering member sufficiently receives heat and melts, but the covering member hinders the laser beam to the base steel plate, and the base steel plate has not sufficiently melted.

  As a second conventional example, as shown in FIG. 9, a 1.2 mm aluminum coating material is disposed on a 1.2 mm aluminum base material (material to be welded), and a semiconductor laser When welding is performed with a welding machine (output: 4 kW, welding speed: 0.8 m / min), there is a problem in that the coating material is thermally deformed and lifted.

  Further, as another third conventional example, as shown in FIG. 10, a Ni-based ultra-thickness of 1.5 mm is formed on the surface of a base steel plate of a precipitation-strengthened Ni-based precision cast alloy having a thickness of 5.5 mm. It was found that cracks occurred in the root portion where stirring with the base material was small when an alloy coating was placed and welding was performed with a semiconductor laser welder (output: 3 kW, welding speed: 65 mm / sec). .

Japanese Patent Laying-Open No. 2002-137059 (Patent Document 1) is disclosed as a method for forming a metal layer having physical resistance characteristics on a base steel plate.
According to Patent Document 1, a punched steel plate having a large number of through holes on the surface of a base steel plate is welded. A wear-resistant metal is welded to each through hole of the punched steel plate, and a large number of overlays are formed on the surface of the base steel plate.
A large number of the overlaid portions are melted and united with the rib portions of the punched steel plate to form an abrasion-resistant hardened metal layer on the surface of the base steel plate.

JP 2002-137059 A

However, in the first, second, and third conventional examples, the laser beam is a structure that melts the base steel plate by the heat from the covering material. Ex.) When there is too much heat in the coating material with the same plate thickness than the base material steel plate and deforms (2nd conventional example), and the base material steel plate does not sufficiently transfer heat, causing cracks in the molten part There is.
In addition, since the disclosed technique of Patent Document 1 is a method in which a welding material having wear resistance is fed by an automatic feeding device such as MIG welding, it is difficult to adjust the necessary overlay thickness of the overlay material. High accuracy and material cost.
Furthermore, the punched steel plate is welded to the base steel plate, the wear-resistant metal (welding material) is melt-filled in the punched hole, and the rib portion of the punched steel plate is melted and welded. This is a problem that increases the man-hours associated with the movement of equipment.

  The present invention has been made to solve such problems, and an object of the present invention is to accurately and inexpensively form a metal layer having physical resistance characteristics on the surface of a base steel plate.

In order to solve this problem, the present invention provides a base steel plate that is a member to be welded,
A flat plate-shaped covering material having physical resistance, which is disposed on the surface of the base steel plate and has a plurality of through holes, and laser welding the base steel plate and the covering material through the through holes. It is characterized by that.

According to this invention, since the laser beam is irradiated along the through hole of the covering material, both the base material steel plate and the covering material are surely melted, the mutual welding is ensured, and the periphery of the through hole is assured. The through hole is closed by welding dripping, and a physical resistance metal layer is formed on the entire surface.
Further, since the flat coating material is used, it is easy to manufacture the molding thickness of the physical property resistant metal layer as desired, and the cost can be reduced by reducing the material cost.

  Preferably, in the present invention, the through holes of the coated steel material have a small number of through holes when the plate thickness is thin, and the number of through holes when the plate thickness is large. It is good to be dense.

According to this invention, when the plate thickness is thin, the number of through holes arranged in the covering material is sparse, and when the plate thickness is thick, the number of through holes arranged is dense. By doing so, when the thickness is small, the welding heat is excessively input and the molten material is repelled or melted so that the formation of the metal layer having a physical property resistant property is prevented from being thinned.
On the other hand, when the plate thickness is thick, heat to the covering material becomes insufficient, the formation of the physical property metal layer due to insufficient melting becomes thin, and the welding (penetration) with the base material steel plate is prevented from being insufficient.

In the present invention, preferably, the relationship between the plate thickness Tb of the covering material, the necessary build-up thickness Ta after melting of the covering material, the through-hole diameter Dh, and the distance L between the through-holes is as follows:
1.5 × Ta ≦ Tb ≦ 5mm
0 <Dh ≦ 1/3 × Tb
Dh ≦ L ≦ 3Dh
It is good to do.

  According to this invention, by determining the relationship between the plate thickness Tb of the coating material, the necessary build-up thickness Ta after melting of the coating material, the through-hole diameter Dh, and the distance L between the through-holes, The welding of the material is ensured, and the necessary build-up thickness Ta is easily secured, and the quality is stabilized.

  In the present invention, preferably, the covering material is a mesh material knitted in a mesh shape.

  According to this invention, by making the coating material a plate material knitted in a mesh shape, the laser beam irradiation spreads over the coating material and the base material steel plate, and the welding in the entire region is ensured, and the coating material and the base material steel plate An air layer is less likely to be generated between and the quality is stabilized.

  In the present invention, it is preferable that the distance between the materials constituting the mesh is increased as the cross-sectional area of the material increases with respect to the required build-up thickness.

  According to this invention, the distance between the materials constituting the mesh is increased as the cross-sectional area of the material increases with respect to the required build-up thickness. Accumulation accuracy is improved, and material costs can be reduced.

  In the present invention, it is preferable that the covering material is configured to start irradiation with the laser beam after fixing an end of the covering material to the base steel plate.

  According to this invention, by fixing the end portion of the covering material to the base steel plate, the melted portion is solidified by the irradiation of the laser beam, so that the position of the covering material at the end portion is shifted and the necessary overlaying is performed. The thickness can be prevented from becoming thicker than the set thickness, and the effect of reducing the material cost can be obtained.

Laser welding of the periphery of the through hole of the covering material and the base material steel plate through the through hole of the covering material ensures that both the base material steel plate and the covering material are melted to ensure mutual welding and penetration. The through hole is closed by welding dripping from the periphery of the hole, and a metal layer having physical property resistance is formed on the entire surface.
Further, since the flat coating material is used, the molding thickness of the metal layer having physical property resistance can be easily manufactured as desired, and the cost can be reduced by reducing the material cost.

1 shows a schematic plan view of a configuration of a first embodiment according to the present invention. The AA arrow line view of FIG. 1 is shown. The B section enlarged view after the welding of FIG. 2 is shown. The construction implementation conditions of 1st Embodiment which concern on this invention are shown. The schematic plan view of the structure of 2nd Embodiment which concerns on this invention is shown. The table shows the relationship between the mesh wire diameter and the mesh wire diameter in the case where the required overlay thickness Ta = 1 in the second embodiment according to the present invention. FIG. 7 shows a relationship diagram between the mesh wire cross-sectional area in FIG. A first conventional example is shown. A second conventional example is shown. A third conventional example will be described.

Embodiments of the present invention will be described below with reference to the drawings.
However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to specific examples unless otherwise specifically described. Only.

(First embodiment)
FIG. 1 is a schematic plan view of the configuration of the first embodiment according to the present invention.
Reference numeral 1 denotes a base steel plate which is a member to be welded, and a flat coating material 2 having physical resistance is fixed to the surface of the base steel plate 1.
As shown in FIG. 2, the laser welding head 6 is set so as to be movable in the right direction (in FIG. 2) above the covering 2 fixed on the surface of the base steel plate 1.
The covering material 2 is a material built up on the surface of the base steel plate 1.
Physical resistance is a metal member with excellent physical properties such as corrosion resistance, wear resistance, heat resistance, etc., and as a member with excellent corrosion resistance, SUS, a member with excellent toughness Indicates titanium, a corrosion resistance, wear resistance, heat resistance, oxidation resistance and creep resistance as a Ni-based superalloy.
The covering material 2 is provided with a large number of circular through holes 3 throughout.

The shape of the coating | covering material 2 is demonstrated based on FIG.
The required build-up thickness Ta of the physical property resistant metal layer formed on the surface of the base steel plate 1 is determined by the required specifications. In this embodiment, the necessary build-up thickness Ta = 1 mm.
The covering material 2 was made of stainless steel (SUS) having corrosion resistance, and the relationship among the thickness Tb, the through hole diameter Dh, and the distance L between the through holes was as follows.
Overlay thickness; Ta = 1mm
Coating material thickness Tb; Tb = 1.5 × Ta = 1.5 mm
Through-hole diameter Dh; Dh = 1/3 × Tb = 0.5 mm
Distance between through holes L; L ≧ Dh = 0.5 mm
It was.
The coating material thickness Tb needs to allow for the amount of the coating material 2 melted by laser welding to flow into the through holes 3 and the amount of shrinkage that occurs when the molten metal resolidifies.
The through hole diameter Dh and the distance L between the through holes vary depending on the coating material thickness Tb. It is necessary to set so that reliable welding can be performed and the necessary build-up thickness Ta can be secured.

That is, by providing the through hole 3 in the covering material 2 having physical resistance, the periphery of the through hole 3 is melted, and the laser beam 61 is directly irradiated to the base steel plate 1 through the through hole 3. It is designed to ensure reliable melting.
Accordingly, since the base steel plate 1 and the covering material 2 are directly welded, the reliability as the covering material is increased.

Further, a plurality of semicircular fixing cutouts 5 are arranged at substantially equal intervals on the entire outer peripheral edge of the covering material 2.
The fixing notch 5 is for fixing the end portion of the covering material 2 to the base material steel plate 1 before laser welding the covering material 2 to the base material steel plate 1 through the through hole 3.
By fixing the end of the covering material 2 to the base material steel plate, it is necessary to prevent shrinkage when the melted portion of the covering material 2 is solidified by laser welding and to shift the covering material covering position of the end portion. It is possible to prevent the build-up thickness Ta from becoming thicker than the set thickness, and to obtain the effect of reducing the material cost and to easily ensure the quality stability.

  Accordingly, without regard to the relationship between the thickness Tb of the covering material 2, the through hole diameter Dh, and the distance L between the through holes, the through hole 3 of the covering material 2 is arranged with the through hole 3 when the plate thickness Tb is thin. When the number of installations is sparse and the plate thickness Tb is thick, the base steel plate 1 is also melted by densely arranging the three through holes, and the melting of the covering material 2 and the melting of the base steel plate 1 are fused. Thus, reliable welding is performed.

FIG. 3 is an enlarged view of part B of FIG. 2, and is a portion where the through hole 3 and the base steel plate 1 are melted by the laser welding head 6. The covering material 2 is welded at the periphery of the through hole 3 and flows into the through hole 3 to form a necessary build-up thickness Ta.
And the base material steel plate 1 is formed with a fusion part M of the base material steel plate 1 and the covering material 2, and the through hole center part is melted most deeply, and it has a conical shape from the through hole center part toward the outer periphery. You can see that it is shallow.

From the above experimental results, the relationship between the plate thickness Tb of the covering material 2, the necessary build-up thickness Ta after melting of the covering material 2, the through hole diameter Dh, and the distance L between the through holes is
1.5 × Ta ≦ Tb ≦ 5mm
0 <Dh ≦ 1/3 × Tb
Dh ≦ L ≦ 3Dh
It was.
That is, when the plate thickness Tb ≦ 5 mm is set, there is a case where there is too much buildup and the covering material and the base steel plate 1 are not sufficiently melted. On the other hand, the thickness Tb ≧ 1.5 × required buildup thickness Ta is set to ensure the necessary buildup thickness Ta when the molten coating material is filled in the through holes.
Furthermore, if the through-hole diameter Dh is too large, it becomes difficult to ensure the required build-up thickness Ta as described above, and when there is no through-hole (through-hole diameter Dh = 0), the base steel plate is not directly irradiated with a laser beam. The base material steel plate 1 and the covering material 2 are not sufficiently melt-bonded.
As for the distance L between the through holes, if the distance L between the through holes is too large due to the relationship between the plate thickness Tb and the through hole diameter Dh, the necessary build-up thickness Ta is increased, resulting in waste of material and high cost. If it is too small, it will be difficult to secure the necessary thickness Ta.
The distance L between the through holes is set to Dh ≦ distance between the through holes L ≦ 3Dh. When the distance L between the through holes is small, it is difficult to secure the necessary build-up thickness Ta.
On the other hand, when the through-hole distance L is large, the possibility of occurrence of a welding failure between the base material steel plate 1 and the covering material 2 increases.
However, in order to ensure the close contact between the base material steel plate 1 and the covering material 2, it is necessary to shorten the distance L between the through holes.
Accordingly, the distance L between the through-holes is set to a range in which Dh is a minimum of 0.5 mm or more and a maximum is 3Dh.

By welding with such a structure (method), the laser beam 61 is irradiated through the through hole 3 of the covering material 2, so that the base steel plate 1 and the covering material 2 are surely melted and welded to each other. And the through hole 3 is closed by welding from the periphery of the through hole 3, and a metal layer having physical property resistance is formed on the entire surface.
In addition, since the flat coating material 2 is used, it is easy to manufacture the molded thickness of the metal layer having physical property resistance as desired, the quality is stable, and the cost can be reduced by reducing the material cost.
Also,

(Second Embodiment)
This embodiment will be described with reference to FIG. 5 and FIG.
In addition, since the welding method of the base material steel plate 1 and the coating | covering material 7 is the same with this 1st Embodiment with respect to 1st Embodiment, it abbreviate | omits about a welding method and demonstrates the shape of the coating | covering material 7. FIG.
Moreover, the same content is attached | subjected the same code | symbol and description is abbreviate | omitted.

FIG. 5A shows a covering material 7 in which a metal material 71 having physical resistance (hereinafter referred to as “wire”) is knitted in a flat plate shape, and FIG. 5B shows a partially enlarged view thereof.
The covering material 7 is formed by braiding wires 71 in a lattice shape, and a distance (gap) Lm between meshes is provided between the wires 71. In FIG. 5B, the mesh space 72 surrounded by the inter-mesh distance Lm is square.
The base steel plate 1 and the wire 71 are welded by the laser beam 61 through the mesh space 72.
In this embodiment, the mesh space 72 has a square shape, but may have a rectangular shape. In short, the necessary build-up thickness Ta is determined by the cross-sectional area of the mesh space 72 into which the melted wire 71 is melted.

The relationship between the wire 71 and the mesh interval Lm when covering the necessary build-up thickness Ta = 1 mm in the present embodiment will be described with reference to FIG.
As already described in the first embodiment, the wire diameter of the wire 71 is such that the melted material of the wire 71 melted by laser welding flows into the mesh space 72 and the amount of shrinkage that occurs when the melted metal resolidifies. It is necessary to expect.
There is a relationship as shown in FIG. 6 between the mesh interval Lm (in the case of a square) and the wire diameter φD.
That is, it can be seen that the mesh distance Lm increases as the wire diameter φD increases. The laser beam 61 melts the wire 71 and also melts the base steel plate 1, and the melting of the wire 71 and the melt of the base steel plate 1 are fused to perform reliable welding.
FIG. 7 shows the relationship between the mesh distance Lm and the wire cross-sectional area mm2.
FIG. 7 shows that the wire cross-sectional area mm2 and the mesh distance Lm are in a proportional relationship.

  In the present embodiment, the mesh-shaped covering material 7 can be easily fixed to the base steel plate 1 by scanning (moving) the laser beam 61 along the outer peripheral edge of the covering material 7.

By adopting such a structure, the coating material 7 is a plate knitted in a mesh shape, so that the laser beam irradiation is closely applied to the coating material and the base steel plate, and welding is ensured in the entire region. An air layer is less likely to be generated between the steel plate and the base steel plate, and the quality is stabilized.
In addition, the distance between the materials composing the mesh is increased as the cross-sectional area of the material increases with respect to the required build-up thickness. Accuracy can be improved, and the material cost can be reduced.

  It can be provided as a build-up welded steel sheet for forming a metal layer of a member having physical resistance on the surface of the base steel sheet.

DESCRIPTION OF SYMBOLS 1 Base material steel plate 2, 7 Coating | covering material 3 Through-hole 5 Notch for fixation 6 Laser welding head 71 Metal strand 72 Mesh space Ta Required build-up thickness Tb Coating material thickness Dh Through-hole diameter L Distance between meshes Lm Between meshes Distance M Fusion part of base steel plate 1 and covering material 2

Claims (6)

A base steel plate that is a member to be welded;
A flat coating material having physical resistance with a plurality of through-holes disposed on the surface of the base steel plate;
A build-up welding structure characterized by laser welding the base steel plate and the covering material through the through hole.   The through hole of the reinforcing steel material is characterized in that when the plate thickness is thin, the number of the through holes is made sparse, and when the plate thickness is thick, the number of the through holes is made dense. The overlay welding structure according to claim 1. The relationship between the plate thickness Tb of the covering material, the necessary build-up thickness Ta after melting of the covering material, the through hole diameter Dh, and the distance L between the through holes is as follows.
1.5 × Ta ≦ Tb ≦ 5mm
0 <Dh ≦ 1/3 × Tb
Dh ≦ L ≦ 3Dh
The build-up welded structure according to any one of claims 1 to 2, wherein   The overlay welding structure according to claim 1, wherein the covering material is a mesh material knitted in a mesh shape.   The overlay welding according to claim 4, wherein the mesh material is configured such that a distance between materials constituting the mesh increases as a cross-sectional area of the material increases with respect to a necessary overlay thickness. Construction.   The overlay welding according to any one of claims 1 to 5, wherein the coating material is configured to start irradiation with the laser beam after fixing an end of the coating material to the base steel plate. Construction.

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