JP2012200736A - Friction agitation processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction agitation processing method for hardly generating the defect of a joining part by reducing load to a friction agitation tool.SOLUTION: A filler 5 is filled in a beveling 4 provided between a first joining material 1 and a second joining material 2, and a pin 6 of the friction agitation processing tool 8 is inserted in the filler. In the friction agitation processing method for agitating parts of the filler, the first joining material and the second joining material, the filler pushes a sintered material sintered so that voids exist in powder to crush the voids.

Description

  Embodiments described herein relate generally to a friction stir processing method.

  In the conventional friction stir processing method, the portion to be repaired by the friction stir processing is filled with a filler, and the friction stir processing is performed with a friction stir tool.

  In order to reduce the load on the friction stir tool, the filler is a powder or a filler material by thermal spraying. The surface layer of the filler is melted with a laser or the like so that the powder or the like is not scattered.

  The shoulder part of the friction stirrer tool needs to be in close contact with the surface of the treatment material, and for the purpose of preventing the occurrence of defects due to the joint gap in the friction stirrer process, pressing the filler filled in the gap from above raises the swell. Eliminate and increase packing density.

  In addition, in order to prevent the friction stir processing part from becoming thinner than the original material, a solid material (multiple pieces and pellet-shaped filler) is filled on and around the seam of the work piece for friction. There is also a method of performing a stirring process.

JP 2007-185683 A JP 2007-29955 A JP 2007-144519 A

  In the friction stir processing method described above, there is a problem that when the powder is filled, the portion to be processed is limited because the powder cannot be held in a posture other than downward.

  In addition, since the powder is pressed, the packing density of the powder is increased to some extent, but the filled powder is only mechanically compressed, and when it is stirred with a friction stir tool, it is very likely to be scattered. For this reason, there is a problem that the effect of powder filling cannot be obtained sufficiently and defects such as cavities occur in the friction stir processing section.

  When filling the solid material, the powder-like scattering does not occur, but the solid material swells and the shoulder portion of the friction stir tool cannot be brought into close contact with the surface of the treatment material. Moreover, when it fills so that a filling material may not rise, there exists a subject that a packing density becomes inadequate.

  The problem to be solved by the present invention is to provide a friction stir processing method that reduces the load on the friction stir tool and makes it difficult to cause defects in the joint.

  In the friction stir processing method of the embodiment, the filler is filled in the groove provided between the first bonding material and the second bonding material, and the pin of the friction stirring processing tool is inserted into the filler. In the friction stir processing method of stirring a part of the filler, the first bonding material, and the second bonding material, the filler is a sintered material obtained by sintering powder so that a cavity exists. The cavity is crushed by pressing.

  In the friction stir processing method of the embodiment, the filler is a sintered material obtained by sintering powder so that cavities exist, and the filler is supplied while being moved in a direction opposite to the friction stir processing direction. Friction stirring is performed.

  In addition, the friction stir processing method of the embodiment is characterized in that the filler is a laminated foil pressed in the laminating direction.

  In the friction stir processing method of the embodiment, the laminated foil is sandwiched and pressed between the first bonding material and the second bonding material to form a bonding portion, and the pin of the friction stirring processing tool is placed in the bonding portion. The laminated foil, the first bonding material, and a part of the second bonding material are agitated.

  Further, the friction stir processing method of the embodiment is characterized in that the filler is a compressed metal foam.

The figure which shows the friction stirring processing method of 1st Embodiment. The figure which shows the friction stirring processing method of 2nd Embodiment. The figure which shows the friction stirring processing method of 3rd Embodiment. The figure which shows the friction stirring processing method of 4th Embodiment.

  Hereinafter, the friction stir processing method of the embodiment will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating a friction stir processing method according to the first embodiment.

  As shown to Fig.1 (a), the 1st joining material 1 and the 2nd joining material 2 of a 3 mm-thick carbon steel material are closely_contact | adhered in the butt | matching part 3, and the groove | channel 4 is processed beforehand. The filler 5 for filling the groove 4 is a carbon steel material similar to the first bonding material 1, but is not a solid material but a sintered material obtained by sintering carbon steel powder. This sintered material is sintered at a lower temperature or in a shorter time than the sintering conditions usually used in powder metallurgy, and the sintered material is insufficiently squeezed, and then pressed to crush the unsintered cavities It is. Such a filler 5 has a density close to 100%, but the cavities are crushed and are simply in contact with each other, and are easily deformed as compared with the solid material. A filler 5 obtained by processing such a sintered pressed material into a shape similar to that of the groove 4 is filled in the groove 4.

  Next, a friction stir processing tool 8 having a pin 6 and a shoulder 7 shown in FIG. 1B is inserted into the filler 5 while rotating.

  As shown in FIG. 1 (c), the pin 6 is inserted into the filler 5, and the filler 5, the first bonding material 1, a part of the second bonding material 2, and the butting portion 3 are stirred, The shoulder 7 rubs the surfaces of the first bonding material 1 and the second bonding material 2. In this state, the friction stir processing is performed by moving the friction stir tool 8 in the friction stir processing direction.

  FIG.1 (d) shows the state after a friction stirring process. In this state, the butted portion 3 before joining disappears and the joined portion 9 is formed.

  Friction stirring conditions may be the same conditions as those for normal carbon steel enriched materials, the rotation speed of the tool is 300 to 500 rpm, the moving speed of the tool is 200 to 500 mm / min, and the tool is PCBN (polycrystalline cubic boron nitride) Was used. The shape of the tool was a pin diameter of 3 mm, a pin length of 2.8 mm, and a shoulder diameter of 10 mm.

  According to the first embodiment, since most of the portion where the pin of the friction stir tool is inserted is replaced with a solid material having a high stirring resistance, a pressed sintered material having a low stirring resistance is used. Can reduce pin consumption. Further, since the stirring resistance is small and the tool rotation torque and the tool pushing load are reduced, it is possible to join steel materials with a friction stirrer that is smaller than conventional ones. In addition, although it is a sintered material with a low deformation resistance, it is pressed to bring the density close to 100%, so that the amount of material supplied into the groove is sufficient, and defects such as cavities in the joints are less likely to occur. Can do. Further, since the filler is a sintered material, the filler can be held even when the filler is supplied in a posture other than downward.

  The filler 5 can be the same effect even if it is a compressed foam metal in which a low density foam metal is compressed to crush the cavity and increase the density.

(Second Embodiment)
FIG. 2 is a diagram illustrating a friction stir processing method according to the second embodiment.

  As shown in FIG. 2A, a first joining material 21 and a second joining material 22 made of carbon steel having a thickness of 4 mm are brought into close contact with each other at a butt portion 23, and a groove 24 is processed in advance.

  Next, as shown in FIG. 2B, the pin 26 of the friction stir tool 28 is rotationally inserted into the groove 24, and the shoulder 27 is rotationally rubbed against the surface of the bonding material. Further, the filler 25 having the same shape as the groove 24 is pressed against the pin 26 from the friction stir processing direction side (right side of the drawing) of the pin 26 from the friction stirring processing direction side (right side of the drawing) in the groove 24. To do.

  In this state, the friction stir tool 28 is moved in the friction stir processing direction (right side in the figure), and the filler 25 is supplied while being moved in the direction opposite to the friction stir processing direction (left side in the figure). The state of forming 29 is shown in FIG.

  FIG. 2D shows a state after joining. The unjoined portion at the left end and the remaining supply material at the right end are processed and removed after joining.

  A friction stir tool made of a PCBN / W-Re alloy composite and having a pin diameter of 4 mm, a pin length of 3.8 mm, and a shoulder diameter of 15 mm was used. The tool rotation speed was 400 rpm and the tool moving speed was 300 mm / min.

  The moving speed of the filler 25 was set as follows. The filler 25 is a carbon steel material similar to the first bonding material 21 and the second bonding material 22, but is not a solid material and is a sintered material in which cavities remain and has a density of 80%. The friction stir tool 28 advances the groove 24 of 300 mm per minute, but when the filler 25 is stopped, only 80% of this volume can be supplied. In order to make this supply amount 100%, the filler 25 is moved in the direction opposite to the friction stir processing direction (the left side in the figure) at a speed of 300 mm / min × (100−80) / 80 = 75 mm / min. Just do it. When the density differs depending on the sintered material, the moving speed of the filler 25 may be set by the above-described calculation method so that the supply amount becomes 100%.

  The moving speed of the filler 25 is not limited to this calculation result, and can be increased or decreased based on the joining result. If there are many burrs discharged out of the joint 29, the supply amount is decreased. If the dent of the joint 29 is large or a cavity defect occurs inside, the supply amount is increased. Further, when the filling material 25 flutters or buckles and cannot be supplied satisfactorily, although not shown, a fixing tool for pressing the filling material 25 into the groove 24 and fixing it may be used as appropriate. .

  According to the second embodiment, since a low-density supply material is used, the load on the pin of the friction stir tool is reduced, and the pin consumption can be reduced. Further, since the stirring resistance is small and the tool rotation torque and the tool pushing load are reduced, it is possible to join steel materials with a friction stirrer that is smaller than conventional ones. In addition, the filler is moved and supplied to compensate for the low density of the filler so that the supply amount to the groove volume is sufficient. Defects such as dents and internal cavities can be made difficult to occur. Further, since the filler is a sintered material, the filler can be held even when the filler is supplied in a posture other than downward.

(Third embodiment)
FIG. 3 is a diagram illustrating a friction stir processing method according to the third embodiment.

  In the friction stir processing method of the second embodiment, as shown in FIG. 3, a high frequency induction heating coil 34 for heating the filler 33 and a pressing roller 35 are provided.

  The filler 33 is supplied into the groove 31 of the material to be joined. The filler 33 is a sintered material having a low density. The filler 33 is heated and softened by the high frequency induction heating coil 34 before being supplied into the groove 31 of the material to be joined. The heated filler 33 is supplied by the pressing roller 35 into the groove 31 of the material to be joined. The friction stir tool 38 having the pin 36 and the shoulder 37, the high-frequency induction heating coil 34, and the pressing roller 36 move in the friction stir processing direction (right side in the drawing) to form a joint 39. The supply amount of the filler 33 may be controlled by the calculation method of the second embodiment so that the supply amount becomes 100%.

  According to the present embodiment, since the low-density sintered material is heated and softened, the load on the pin of the friction stir tool is reduced and pin wear can be reduced. Further, since the filler is pressed by the pressing roller, the supply material is not fluttered or deformed, the supply amount can be stabilized, and defects such as cavities can be made difficult to occur at the joint. Further, since the filler is a sintered material, the filler can be held even when the filler is supplied in a posture other than downward.

(Fourth embodiment)
FIG. 4 is a diagram illustrating a friction stir processing method according to the fourth embodiment.

  FIG. 4A shows a case where the filler is a horizontal laminated foil 44 in the friction stir processing method of the first embodiment.

  FIG. 4 (b) shows a joining portion formed by pressing a vertical laminated foil 45 between the first joining material 41 and the second joining material 42 of a carbon steel material having a plate thickness of 3 mm and pressing them from both sides. . In this case, groove processing is not necessary.

  FIG. 4C shows a case where the upper and lower portions of the vertical laminated foil 45 of FIG. In this case, scattering of the laminated foil due to the friction stirring process can be prevented.

  The horizontal laminated foil 44 and the vertical laminated foil 45 are carbon steel materials similar to the first bonding material 41 and the second bonding material 42, but are pressed in the stacking direction. The horizontal laminated foil 4 and the vertical laminated foil 45 have a density close to 100%, but the laminated foils are merely in contact with each other and are easily deformed as compared with the solid material. The laminating direction of the horizontal laminated foil 44 may be either vertical or horizontal with respect to the butt portion 43.

  Friction stirring conditions may be the same conditions as those for normal carbon steel enriched materials, the rotation speed of the tool is 300 to 500 rpm, the moving speed of the tool is 200 to 500 mm / min, and the tool is PCBN (polycrystalline cubic boron nitride) Was used. The shape of the tool was a pin diameter of 3 mm, a pin length of 2.8 mm, and a shoulder diameter of 10 mm.

  According to the fourth embodiment, since most of the portion where the pin of the friction stir tool is inserted is replaced with a solid material having a high stirring resistance, a laminated foil having a low stirring resistance is used, so the load on the pin is reduced. Pin consumption can be reduced. Further, since the stirring resistance is small and the tool rotation torque and the tool pushing load are reduced, it is possible to join steel materials with a friction stirrer that is smaller than conventional ones. In addition, although it is a sintered material with a low deformation resistance, it is pressed to bring the density close to 100%, so that the amount of material supplied into the groove is sufficient, and defects such as cavities in the joints are less likely to occur. Can do. Further, since the filler is a laminated foil, the filler can be held even when the filler is supplied in a posture other than downward.

  In addition, although the example of the butt joint was shown in the 1st-4th embodiment, the same effect is acquired even if it is a T joint and a square joint.

  Further, although common to the first to fourth embodiments, the material to be joined is not limited to carbon steel, other hard materials such as Ni-base superalloy, Ti alloy, stainless steel, or copper alloy Other metal materials may be used. Further, the friction stir processing portion is not limited to the joining of the entire plate thickness, but can be a partial plate thickness or an overlay of the surface portion. Furthermore, the present embodiment can be applied even when the first bonding material, the second bonding material, and the filler or the supply material are different.

  According to the friction stir processing method of at least one embodiment described above, it is possible to reduce the load on the friction stir tool and make it difficult to cause defects in the joint.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1, 21, 41 First bonding material 2, 22, 42 Second bonding material 3, 23, 32, 43 Butting portion 4, 24, 31 Groove 5, 25, 33 Filling material 6, 26, 36 Pin 7 27, 37 Shoulder 8, 28, 38 Friction stir tool 9, 29, 39 Joint 34 High frequency induction heating coil 35 Pressing roller 44 Horizontal laminated foil 45 Vertical laminated foil 46 Foam metal

Claims (7)

Filling a filler in a groove provided between the first bonding material and the second bonding material;
Insert the pin of the friction stir processing tool into the filler,
In the friction stir processing method of stirring a part of the filler, the first bonding material, and the second bonding material,
The friction stir processing method, wherein the filler is crushed by pressing a sintered material obtained by sintering powder so that a cavity exists. Supplying a filler into a groove provided between the first bonding material and the second bonding material;
Insert the pin of the friction stir processing tool into the groove,
In the friction stir processing method of stirring a part of the filler, the first bonding material, and the second bonding material,
The filler is a sintered material obtained by sintering powder so that cavities exist,
A friction stir processing method, wherein the filler is supplied while being moved in a direction opposite to the friction stir processing direction, and the friction stir processing is performed.   The friction stir processing method according to claim 2, wherein the filler is heated before being fed into the groove. Filling a filler in a groove provided between the first bonding material and the second bonding material;
Insert the pin of the friction stir processing tool into the filler,
In the friction stir processing method of stirring a part of the filler, the first bonding material, and the second bonding material,
The friction stir processing method, wherein the filler is a laminated foil pressed in the laminating direction.   The friction stir processing method according to claim 4, wherein the upper and lower portions of the laminated foil are made of foam metal. A laminated foil is sandwiched and pressed between the first bonding material and the second bonding material to form a bonded portion,
Insert the pin of the friction stir processing tool into the joint,
A friction stir processing method comprising stirring the laminated foil, the first bonding material, and a part of the second bonding material. Filling a filler in a groove provided between the first bonding material and the second bonding material;
Insert the pin of the friction stir processing tool into the filler,
In the friction stir processing method of stirring a part of the filler, the first bonding material, and the second bonding material,
The friction stir processing method, wherein the filler is a compressed foam metal.

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