Disclosure of Invention
Technical problem to be solved by the invention
In friction stir welding, when a rotary tool is pushed into a start position of a metal member to be welded, which is set in a butt portion, or when the rotary tool is separated from an end position set in the butt portion, the rotary tool is moved in the vertical direction, and therefore friction heat at the start position or the end position becomes excessive. As a result, a poor joint may occur. Further, in friction stir welding, it is desirable to reduce the generation of burrs.
Accordingly, an object of the present invention is to provide a method for manufacturing a heat transfer plate, which can reduce the generation of burrs and can suppress frictional heat generated when a rotary tool is pushed in or pulled out to be desirably joined.
In order to solve the technical problems, the invention is characterized by comprising: a cover plate insertion step of inserting a cover plate into a cover groove formed around a recess opening in a front surface of a base member, providing a gap between a side wall of the cover groove and a side surface of the cover plate, and forming a butt portion; and a main joining step of relatively moving a rotary tool including a base end side pin and a tip end side pin along the abutting portion to friction stir the abutting portion, wherein a taper angle of the base end side pin is larger than a taper angle of the tip end side pin, a stepped portion is formed on an outer peripheral surface of the base end side pin, and in the main joining step, after the rotating tip end side pin is inserted into a start position set on a front surface of the base member, the rotary tool is moved to a position where a rotation center axis of the rotary tool overlaps the abutting portion, and the tip end side pin is gradually pressed into the gap until a predetermined depth, and when the rotary tool is relatively moved along the abutting portion, the outer peripheral surface of the base end side pin is brought into contact with the front surface of the base member and the front surface of the cover plate, and a plastic fluidizing material generated by friction stirring is pressed into the gap by the outer peripheral surface of the base end side pin.
The present invention is characterized by comprising: a cover plate insertion step of inserting a cover plate into a cover groove formed around a recess opening in a front surface of a base member, providing a gap between a side wall of the cover groove and a side surface of the cover plate, and forming a butt portion; and a main joining step of relatively moving a rotary tool including a base end side pin and a tip end side pin along the butt joint portion to friction stir the butt joint portion, wherein a taper angle of the base end side pin is larger than a taper angle of the tip end side pin, and a stepped portion is formed on an outer peripheral surface of the base end side pin, and in the main joining step, the tip end side pin is inserted from a start position set on the butt joint portion, moved in a traveling direction, and the tip end side pin is gradually pressed to a predetermined depth, and when relatively moving the rotary tool along the butt joint portion, an outer peripheral surface of the base end side pin is brought into contact with a front surface of the base member and a front surface of the cover plate, and a plastic fluidizing material generated by friction stirring is pressed into and filled into the gap by the outer peripheral surface of the base end side pin.
The present invention is characterized by comprising: a cover plate insertion step of inserting a cover plate into a cover groove formed around a recess opening in a front surface of a base member, providing a gap between a side wall of the cover groove and a side surface of the cover plate, and forming a butt portion; and a main joining step of relatively moving a rotary tool including a base end side pin and a tip end side pin along the butt joint portion to friction stir the butt joint portion, wherein a taper angle of the base end side pin is larger than a taper angle of the tip end side pin, a stepped portion is formed on an outer peripheral surface of the base end side pin, and in the main joining step, when relatively moving the rotary tool along the butt joint portion, the outer peripheral surface of the base end side pin is brought into contact with a front surface of the base member and a front surface of the cover plate, and plastic flow material generated by friction stirring is pressed into and filled into the gap through the outer peripheral surface of the base end side pin, an end position is set to the front surface of the base member, and after friction stirring joining of the butt joint portion, the rotary tool is moved to the end position, and the tip end side pin is gradually pulled out from the base member to disengage the rotary tool from the base member at the end position.
The present invention is characterized by comprising: a cover plate insertion step of inserting a cover plate into a cover groove formed around a recess opening in a front surface of a base member, providing a gap between a side wall of the cover groove and a side surface of the cover plate, and forming a butt portion; and a main joining step of relatively moving a rotary tool including a base end side pin and a tip end side pin along the butt joint portion to friction stir the butt joint portion, wherein a taper angle of the base end side pin is larger than a taper angle of the tip end side pin, a stepped portion is formed on an outer peripheral surface of the base end side pin, and in the main joining step, when relatively moving the rotary tool along the butt joint portion, the outer peripheral surface of the base end side pin is brought into contact with a front surface of the base member and a front surface of the cover plate, and plastic flow material generated by friction stirring is pressed into and filled into the gap through the outer peripheral surface of the base end side pin, an end position is set on the butt joint portion, and after friction stirring joining of the butt joint portion, the rotary tool is moved to the end position, and the tip end side pin is gradually pulled out from the base member and the cover plate to separate the rotary tool from the base member and the cover plate at the end position.
According to the above manufacturing method, the friction heat at the abutting portion can be prevented from becoming excessive by moving the rotary tool to a position overlapping the abutting portion and gradually pushing the tip-side pin to a predetermined depth. Further, by moving the rotary tool over the abutting portion and gradually pushing the tip-side pin up to a prescribed depth, it is possible to prevent the frictional heat from becoming excessive at a point on the abutting portion. Further, by moving the rotary tool to the end position and gradually pulling out the tip end side pin from the predetermined depth, the frictional heat at the abutting portion can be prevented from becoming excessively large. Further, by moving the rotary tool over the abutting portion and gradually pulling out the tip-side pin from the predetermined depth, it is possible to prevent the frictional heat from becoming excessive at a point on the abutting portion. Further, since the plastic fluidizing material can be pressed by the outer peripheral surface of the base end side pin, the occurrence of burrs can be suppressed.
In addition, it is preferable that the cover plate insertion step be preceded by a heat medium pipe insertion step in which a heat medium pipe is inserted into the groove. According to the above manufacturing method, the heat transfer plate including the heat medium pipe can be easily manufactured.
In the main joining step, it is preferable that the flat surface of the tip-side pin is in contact with the bottom surface of the cover groove when the rotary tool is relatively moved along the abutting portion. According to the above manufacturing method, the bonding strength between the base member and the cover plate can be improved.
Further, it is preferable that the main joining step be preceded by a temporary joining step in which the butt joint is temporarily joined. According to the above manufacturing method, positional displacement of the base member and the cover plate and cracking between the base member and the cover plate in the main joining process can be prevented,
in the temporary joining step, it is preferable that the rotary tool used for friction stir welding includes a base end side pin and a tip end side pin, the taper angle of the base end side pin is larger than the taper angle of the tip end side pin, a stepped portion is formed on an outer peripheral surface of the base end side pin, and friction stir welding is performed in a state in which the outer peripheral surface of the base end side pin is brought into contact with a front surface of the base member and a front surface of the cover plate.
According to the above manufacturing method, the base member and the cover plate can be pressed by the outer peripheral surface of the base-end-side pin having a large taper angle, and therefore, the generation of burrs can be reduced, and the base-end-side pin can be bonded desirably.
Effects of the invention
According to the method for manufacturing a heat transfer plate of the present invention, generation of burrs can be reduced, and frictional heat generated at the time of press-in or release of a rotary tool can be suppressed to be desirably joined.
Detailed Description
Embodiments of the present invention will be described with reference to the accompanying drawings as appropriate. First, a joining rotary tool (rotary tool) F used in the joining method according to the embodiment of the present invention will be described. The main joining rotation tool F is a tool for friction stir joining. As shown in fig. 1, the main joint rotary tool F is made of, for example, tool steel, and is mainly composed of a base shaft portion F1, a base end side pin F2, and a tip end side pin F3. The base shaft portion F1 is cylindrical and is a portion connected to the main shaft of the friction stir device.
The base end side pin F2 is continuous with the base shaft portion F1, and tapers toward the front end. The base end side pin F2 has a truncated cone shape. The taper angle a of the base end side pin F2 may be appropriately set, for example, 135 ° to 160 °. If the taper angle a is less than 135 ° or greater than 160 °, the joint surface roughness after friction stirring becomes large. The taper angle a is larger than a taper angle B of a tip end side pin F3 described later. As shown in fig. 2, a stepped pin stepped portion F21 is formed over the entire height direction on the outer peripheral surface of the base end side pin F2. The pin stepped portion F21 is formed in a spiral shape so as to be wound right or left. That is, the pin stepped portion F21 is spiral in a plan view and stepped in a side view. In the present embodiment, since the main joint rotary tool F is rotated rightward, the pin stepped portion F21 is set to surround leftward from the base end side toward the tip end side.
In addition, when the main joint rotary tool F is rotated leftward, the pin stepped portion F21 is desirably set so as to surround from the base end side toward the tip end side. Accordingly, the plastic fluidizing material is guided toward the front end side by the pin stepped portion F21, and therefore, the metal overflowing to the outside of the joined metal members can be reduced. The pin step portion F21 is composed of a step bottom surface F21a and a step side surface F21 b. The distance X1 (horizontal distance) between the vertexes F21C, F21C of the adjacent pin level difference portions F21 is appropriately set according to the level difference angle C and the height Y1 of the level difference side surface F21b described later.
The height Y1 of the stepped side surface F21b may be appropriately set, for example, to 0.1 to 0.4mm. If the height Y1 is less than 0.1mm, the bonding front roughness becomes large. On the other hand, if the height Y1 is greater than 0.4mm, the bonding surface roughness tends to become large, and the number of effective level difference portions (the number of pin level difference portions F21 in contact with the metal member to be bonded) also decreases.
The difference angle C between the bottom surface F21a and the side surface F21b may be set appropriately, but is set to 85 ° to 120 °, for example. The level difference bottom surface F21a is parallel to the horizontal plane in the present embodiment. The level difference bottom surface F21a may be inclined in a range of-5 ° to 15 ° with respect to the horizontal plane from the rotation axis of the tool to the outer circumferential direction (negative below the horizontal plane and positive above the horizontal plane). The distance X1, the height Y1 of the stepped side surface F21b, the stepped angle C, and the angle of the stepped bottom surface F21a with respect to the horizontal plane are appropriately set so that the plastic fluidizing material does not stagnate and adhere to the inside of the pin stepped portion F21 but is discharged to the outside when friction stirring is performed, and the plastic fluidizing material can be pressed with the stepped bottom surface F21a to reduce the joint surface roughness.
As shown in fig. 1, the tip end side pin F3 is formed continuously with the base end side pin F2. The tip end side pin F3 has a truncated cone shape. The tip of the tip-side pin F3 is a flat surface F4. The flat surface F4 is perpendicular to the axis of rotation of the tool. The taper angle B of the tip end side pin F3 is smaller than the taper angle a of the base end side pin F2. As shown in fig. 2, a spiral groove F31 is engraved in the outer peripheral surface of the tip end side pin F3. The spiral groove F31 may be formed around the base end side or the tip end side of the main joint rotary tool F in the present embodiment.
In addition, when the main joint rotary tool F is rotated leftward, the spiral groove F31 is desirably set so as to surround rightward from the base end side toward the tip end side. Accordingly, the plastic fluidizing material is guided toward the front end side by the spiral groove F31, and therefore, the metal overflowing to the outside of the joined metal members can be reduced. The spiral groove F31 is formed of a spiral bottom surface F31a and a spiral side surface F31 b. The distance (horizontal distance) between the vertexes F31c, F31c of the adjacent spiral grooves F31 is set to the length X2. The height of the spiral side surface F31b is set to be a height Y2. The spiral angle D formed by the spiral bottom surface F31a and the spiral side surface F31b is formed, for example, at 45 ° to 90 °. The spiral groove F31 increases frictional heat by contact with the joined metal member, and includes an action of guiding the plastic fluidizing material toward the front end side.
The main joint rotary tool F can be appropriately changed in design.
Fig. 3 is a side view showing a first modification of the main joint rotary tool of the present invention. As shown in fig. 3, in the main joint rotary tool FA according to the first modification, the step angle C formed by the step bottom surface F21a and the step side surface F21b of the pin step portion F21 is 85 °. The level difference bottom surface F21a is parallel to the horizontal plane. In this way, the stepped bottom surface F21a may be parallel to the horizontal plane, and the stepped angle C may be set at an acute angle in a range where the plastic fluidizing material does not remain in the pin stepped portion F21 and adhere to the pin stepped portion F during friction stir welding, but is discharged to the outside.
Fig. 4 is a side view showing a second modification of the main joint rotary tool of the present invention. As shown in fig. 4, in the main joint rotary tool FB of the second modification, the step angle C of the pin step portion F21 is 115 °. The level difference bottom surface F21a is parallel to the horizontal plane. In this way, the level difference bottom surface F21a may be parallel to the horizontal plane, and the level difference angle C may be an obtuse angle within a range functioning as the pin level difference portion F21.
Fig. 5 is a side view showing a third modification of the main joint rotary tool of the present invention. As shown in fig. 5, in the main joint rotary tool FC of the third modification, the stepped bottom surface F21a is inclined upward from the horizontal plane by 10 ° from the rotational axis of the tool to the outer circumferential direction. The level difference side F21b is parallel to the plumb face. In this way, the stepped bottom surface F21a may be formed so as to be inclined upward from the horizontal plane toward the outer circumferential direction from the rotation axis of the tool within a range in which the plastic fluidizing material can be pressed during friction stir. The first to third modifications of the main joint rotary tool can also provide the same effects as those of the following embodiments.
First embodiment
Next, the heat transfer plate 1 of the first embodiment will be described. The "front" in the following description refers to the surface opposite to the "back". As shown in fig. 6, the heat transfer plate 1 of the present embodiment mainly includes a base member 2 and a cover plate 5. The base member 2 has a substantially rectangular parallelepiped shape. A recess 3 and a cover groove 4 are formed in the base member 2. The material of the base member 2 and the cover plate 5 is not particularly limited as long as friction stir is possible, but in the present embodiment, an aluminum alloy is used.
The recess 3 communicates from one side face to the other side face at the center of the base member 2. The groove 3 is concavely arranged on the bottom surface of the cover groove 4. The bottom of the groove 3 is arc-shaped. The opening of the recess 3 is open to the front face 2a side of the base member 2.
The cover groove 4 has a width larger than that of the groove 3, and is formed continuously with the groove 3 on the front face 2a side of the groove 3. The lid groove 4 is rectangular in cross section and is open toward the front face 2a side.
The cover plate 5 is a plate-like member inserted into the cover groove 4. The base member 2 and the cover plate 5 are integrated by friction stir joining. The space surrounded by the groove 3 of the heat transfer plate 1 and the lower surface of the cover plate 5 is a flow path through which fluid flows.
Next, a method of manufacturing the heat transfer plate according to the first embodiment will be described. In the method of manufacturing the heat transfer plate, a preparation process, a cover plate insertion process, a temporary joining process, and a main joining process are performed.
As shown in fig. 7A and 7B, the preparation step is a step of preparing the base member 2 and the cover 5. The base member 2 may be formed with the recess 3 and the lid groove 4 by cutting using an end mill or the like, or the base member 2 may be formed with the recess 3 and the lid groove 4 in advance by casting, extrusion, or the like. The cover plate 5 can be molded by extrusion molding, for example.
As shown in fig. 7B, the lid plate insertion step is a step of inserting the lid plate 5 into the lid groove 4. The pair of side walls of the cover groove 4 are abutted against the pair of side surfaces of the cover plate 5 to form abutting portions J1, J2. A fine gap is formed in the abutting portions J1, J2. After that, even when a minute gap is formed between the two surfaces to be butted like the butted portions J1 and J2, it is also called a "butted portion". The width of the gap may be appropriately set, for example, about 0.1mm to 1.0 mm. The front face 5a of the cover plate 5 is coplanar with the front face 2a of the base member 2. The front surface 2a of the base member 2 is referred to as "front surface 2a1" on one side in the width direction and as "front surface 2a2" on the other side, as required.
As shown in fig. 8 and 9, the temporary joining step is a step of performing friction stir welding on the butt portions J1 and J2 in advance using the temporary joining rotation tool FD. The temporary joining rotation tool FD has the same structure as the main joining rotation tool F, and includes a base shaft portion F1D, a base end side pin F2D, and a tip end side pin F3D. The temporary bonding rotary tool FD is smaller than the main bonding rotary tool F.
In the temporary joining step, the friction stir welding of the butt joint J1 is performed with the start position set on one side in the extending direction of the butt joint J1 and the end position set on the other side in the extending direction. In the temporary joining step, friction stir welding is performed in a state in which the outer peripheral surface of the base end side pin F2D is brought into contact with the front surface 2a of the base member 2 and the front surface 5a of the lid plate 5. A plasticized region W1 is formed on the movement locus of the temporary joining rotation tool FD. The abutting portion J2 is also temporarily joined in the same manner.
The temporary joining may be performed continuously or intermittently to the butt joint portions J1 and J2. Further, the temporary joining rotation tool FD may be moved at the start position and gradually pushed in. Further, the temporary joining rotation tool FD may be moved and gradually pulled out at the end position. The start position and the end position of the temporary bonding step may be set on the front surface 2a of the base member 2.
The main joining step is a step of friction stir welding the butt portions J1 and J2 using the main joining rotary tool F. As shown in fig. 9, in the main joining step, friction stir welding is continuously performed in three sections, that is, a press-in section from the start position SP1 to the intermediate point S1 on the abutting portion J1, a main section from the intermediate point S1 to the intermediate point S2, and a disengagement section from the intermediate point S2 to the end position EP 1. The start position SP1 is set at a position distant from the abutting portion J1 in the front face 2a1 of the base member 2. In the present embodiment, the angle formed by the line segment connecting the start position SP1 and the intermediate point S1 and the abutting portion J1 is set to be an obtuse angle.
In the press-in section of the main joining step, friction stir welding is performed from the start position SP1 to the intermediate point S1 as shown in fig. 10. In the press-in section, the tip end side pin F3 rotating rightward is inserted into the start position SP1, and the tip end side pin F3 is moved to the intermediate point S1. At this time, as shown in fig. 10, the tip end side pin F3 is gradually pushed in so as to reach a predetermined "predetermined depth" at least before reaching the intermediate point S1. That is, the main joining rotation tool F is not caused to stay at one place, but is caused to move and gradually descend on the abutting portion J1.
After reaching the intermediate point S1, the friction stir welding is directly transferred to the main section. As shown in fig. 10 and 11, in the main section, the main joining rotary tool F is moved so that the rotation center axis of the tip end side pin F3 overlaps the abutting portion J1. The "predetermined depth" refers to the insertion depth of the tip end side pin F3 in the main section of the abutting section J1. In the main section, the "predetermined depth" of the tip end side pin F3 is set so that the flat surface F4 of the tip end side pin F3 reaches the bottom surface 4a of the lid groove 4. The "predetermined depth" of the distal pin F3 may be set appropriately, for example, so that the distal pin F3 does not reach the level difference bottom surface 4a.
As shown in fig. 9 and 12, after the main joint rotary tool F reaches the intermediate point S2, the main joint rotary tool F is directly shifted to the disengagement section. In the disengagement section, as shown in fig. 12, the tip end side pin F3 is gradually moved upward between the intermediate point S2 and the end position EP1, and the tip end side pin F3 is disengaged from the base member 2 at the end position EP 1. That is, the main joint rotary tool F is not caused to stay at one position, but is moved to the end position EP1 and gradually pulled out (lifted). The end position EP1 of the present embodiment is set at a position where an angle formed by a line segment connecting the end position EP1 and the intermediate point S2 and the abutting portion J1 is an obtuse angle. A plasticized region W1 is formed on the movement locus of the main joining rotary tool F.
In the main joining step, the start position SP2, the end position SP2, and the intermediate points S1 and S2 are set for the butt joint portion J2, and friction stir welding is performed in the same manner as in the butt joint portion J1.
According to the method of manufacturing the heat transfer plate of the present embodiment described above, in the insertion section of the main joining step, the main joining rotary tool F is moved from the start positions SP1 and SP2 to the positions overlapping the butting portions J1 and J2, and the tip end side pins F3 are gradually pushed in to the predetermined depth, whereby the frictional heat at the butting portions J1 and J2 can be prevented from becoming excessively large.
Similarly, in the disengagement section of the main joining step, the main joining rotary tool F is moved from the position overlapping the abutting portions J1 and J2 to the end positions EP1 and EP2, and the tip end side pin F3 is gradually lifted from the predetermined depth to disengage, whereby the frictional heat at the abutting portions J1 and J2 can be prevented from becoming excessively large. In this way, by preventing the frictional heat at the butt joint portions J1, J2 from becoming excessive, poor joining of the butt joint portions J1, J2 can be prevented.
In the conventional method for manufacturing the heat transfer plate, a separate joint is provided at the end of the base member, and the start position and the end position of the rotary tool are set at the joint. However, according to the present embodiment, since a joint is not required, the number of parts can be reduced, and the number of man-hours can be reduced.
In the main joining step of the present embodiment, friction stir is performed in a state where the outer peripheral surface of the base end side pin F2 is in contact with the front surface 2a of the base member 2 and the front surface 5a of the cover plate 5, so that burrs can be reduced. Further, the plastic flow material can be pressed by the outer peripheral surface of the base end side pin F2, and therefore, the level difference groove formed on the joining surface (the front face 2a of the base member 2 and the front face 5a of the cover plate 5) can be reduced, and the bulge formed in the vicinity of the level difference groove can be eliminated or reduced. Further, since the stepped pin stepped portion F21 of the base end side pin F2 is shallow and the outlet is large, it is easy to discharge the plastic fluidizing material to the outside of the pin stepped portion F21 while pressing the plastic fluidizing material with the stepped bottom surface F21 a. Therefore, even if the plastic fluidizing material is pressed by the base end side pin F2, the plastic fluidizing material is not easily adhered to the outer peripheral surface of the base end side pin F2. Thus, the bonding surface roughness can be reduced, and the bonding quality can be desirably stabilized.
In the main joining step, the front surface 2a of the base member 2 and the front surface 5a of the cover 5 are pressed by the outer peripheral surface of the base end pin F2 and friction stir is performed, so that the joining portion can be prevented from becoming insufficient in metal, and the plastic fluidizing material can be pressed into and filled in the gap between the abutting portions J1 and J2. In other words, even when the gap is provided in the butt joint portions J1, J2 like in the main joining step, the plastic fluidizing material can be reliably filled into the butt joint portions J1, J2. Thus, even if the molding accuracy of the lid groove 4 and the lid plate 5 of the base member 2 is not high, the joining can be desirably performed.
In the main joining step, the flat surface F4 of the tip end side pin F3 is set to reach the bottom surface 4a of the lid groove 4, so that the joining strength between the base member 2 and the lid plate 5 can be improved.
Further, by performing the temporary joining process, positional displacement of the base member 2 and the cover 5 and cracking of the butting portions J1, J2 in the main joining process can be prevented. The temporary joining step may be performed by welding or by using another rotary tool, and by friction stirring while bringing the outer peripheral surface of the base end side pin FD2 of the temporary joining rotary tool FD into contact with the front surface 2a of the base member 2 and the front surface 5a of the cover plate 5, the occurrence of burrs can be suppressed.
In the temporary bonding step, the temporary bonding rotary tool FD may be moved at the start position and gradually pushed in.
In the temporary joining step, the temporary joining rotary tool FD may be moved at the end position and gradually separated.
In the main joining step, the positions of the start positions SP1 and SP2 may be appropriately set, and the angles formed between the start positions SP1 and SP2 and the abutting portions J1 and J2 may be set to be obtuse, so that the movement speed of the main joining rotary tool F may be smoothly shifted to the main section at the intermediate points S1 and S2 without being lowered. This prevents the friction heat from becoming excessively large due to the main joint rotating tool F stopping at the abutting portions J1, J2 or the moving speed decreasing. Further, by setting the end positions EP1 and EP2 in the same manner as the start positions SP1 and SP2, the main joint rotary tool F can be smoothly moved from the normal section to the disengagement section.
In the main joining step, the rotational speed of the main joining rotational tool F may be constant or may be variable. In the press-in section of the main joining step, V1 > V2 may be set when V1 is the rotational speed of the main joining rotational tool F at the start position SP1 and V2 is the rotational speed of the main joining rotational tool F between the intermediate points S1 to S2. The rotation speed V2 is a constant rotation speed set in advance in the abutting portions J1, J2. That is, the rotational speed may be set to be high in advance at the start positions SP1 and SP2, gradually reduced in the press-in section, and shifted to the main section.
In the disengagement section of the main engagement process, V3 > V2 may be set when V2 is the rotational speed of the main engagement rotary tool F between the intermediate points S1 to S2 and V3 is the rotational speed of the main engagement rotary tool F at the time of disengagement at the end position EP 1. That is, after the transition to the disengagement section, the rotational speed may be gradually increased toward the end positions EP1 and EP2, and the main engagement rotary tool F may be disengaged. When the main joining rotary tool F is pressed into or separated from the joined metal members, the small pressing force in the press-in section or the separation section can be compensated for by the rotation speed by setting as described above, and therefore, friction stir welding can be desirably performed.
Modification of the first embodiment
Next, a method of manufacturing a heat transfer plate according to a modification of the first embodiment of the present invention will be described. As shown in fig. 13, the method of manufacturing a heat transfer plate according to a modification of the first embodiment differs from the first embodiment in that the positions of the start position SP2 and the end position EP2 are set on the butted portion J2 during friction stir welding of the butted portion J2 in the main joining step. In the modification of the first embodiment, a description will be given centering on a portion different from the first embodiment.
In the method of manufacturing the heat transfer plate according to the modification of the first embodiment, the preparation step, the placement step, and the main joining step are performed. The preparation step and the placement step are the same as those of the first embodiment.
Friction stir at the butt joint portion J1 in the main joining step is performed in the same manner as in the first embodiment. In the modification of the first embodiment, in friction stir welding of the abutting portion J2, as shown in fig. 13, the start position SP2 and the end position EP2 are set on the abutting portion J2. In the main joining step, friction stir is continuously performed in three sections, that is, an insertion section from the start position SP2 to the intermediate point S1, a main section from the intermediate point S1 to the intermediate point S2 on the abutting portion J2, and a disengagement section from the intermediate point S2 to the end position EP2, so that the rotation center axis of the tip end side pin F3 overlaps the abutting portion J2.
As shown in fig. 13, friction stir is performed in the press-in section from the start position SP2 to the intermediate point S1. In the press-in section, the tip end side pin F3 rotating rightward is inserted into the start position SP2 on the abutting portion J2, and the tip end side pin F3 is moved to the intermediate point S1. At this time, the distal pin F3 is gradually pushed in so as to reach a predetermined "predetermined depth" at least before reaching the intermediate point S1. That is, the main joining rotation tool F is not caused to stay at one place, but is caused to move on the abutting portion J2 and gradually descend. After reaching the intermediate point S1, the friction stir welding is directly performed in the main section, and the main welding rotary tool F is moved over the butt joint J2. The predetermined depth is the same as that of the first embodiment.
As shown in fig. 13, after the main joint rotary tool F reaches the intermediate point S2, the main joint rotary tool F is directly shifted to the disengagement section. In the disengagement section, the tip end side pin F3 is gradually moved upward from a predetermined depth between the intermediate point S2 and the end position EP2 on the abutting portion J2, and the tip end side pin F3 is disengaged from the base member 2 at the end position EP 2. That is, the main joining rotation tool F is not caused to stay at one place, but is caused to move on the abutting portion J2 and gradually pulled out.
According to the modification of the first embodiment described above, the substantially same effects as those of the first embodiment can be obtained. Further, by moving the main joining rotary tool F on the abutting portion J2 and gradually pushing the tip end side pin F3 up to a predetermined depth, it is possible to prevent the frictional heat from becoming excessively large at a point on the abutting portion J2. Further, by moving the main joining rotary tool F on the abutting portion J2 and gradually pulling out the tip end side pin F3 from the predetermined depth, it is possible to prevent the frictional heat from becoming excessively large at a point on the abutting portion J2. Further, since the plastic fluidizing material can be pressed by the outer peripheral surface of the base end side pin F2, the occurrence of burrs can be suppressed.
Further, if the start position SP2 and the end position EP2 are set at the abutting portion J2 as in the modification of the first embodiment, the plasticized region W remaining in the front surface 2a2 can be made smaller. In the modification of the first embodiment, the start position SP1 and the end position EP1 may be set in the abutting portion J1 even during friction stir at the abutting portion J1.
Second embodiment
Next, a method of manufacturing a heat transfer plate according to a second embodiment of the present invention will be described. The heat transfer plate 1B of the present embodiment is different from the heat transfer plate 1 of the first embodiment in that it includes heat medium tubes 6. The heat medium pipe 6 is a member through which a fluid flows.
In the method of manufacturing the heat transfer plate according to the present embodiment, the preparation step, the heat medium pipe insertion step, the cover plate insertion step, the temporary joining step, and the main joining step are performed. The preparation step, the lid insertion step, the temporary bonding step, and the main bonding step of the present embodiment are the same as those of the first embodiment. The manufacturing method of the present embodiment is different from the first embodiment in that a heat medium pipe insertion process is performed. In this embodiment, a description will be given mainly of a part different from the first embodiment.
As shown in fig. 14B, the heat medium pipe insertion step is a step of inserting the heat medium pipe 6 into the groove 3 of the base member 2 (see fig. 14A) prepared in the preparation step. The dimensions of the grooves 3 and the heat medium tubes 6 may be appropriately set, but in the present embodiment, the outer diameter of the heat medium tubes 6 is substantially the same as the width and depth of the grooves 3.
In the lid plate insertion step of the present embodiment, when the lid plate 5 is inserted into the lid groove 4, the recess 3, the lower surface of the lid plate 5, and the heat medium pipe 6 form a void Q as shown in fig. 14B. In the case of forming the void Q in the above manner, the void Q may be filled in through the main bonding step as shown in fig. 15. By narrowing the widths of the cover groove 4 and the cover plate 5, the positions of the abutting portions J1, J2 are made to be close to the heat medium pipe 6 and the void Q, and in the main joining step, the plastic fluidizing material formed by the main joining rotary tool F can be caused to flow into the void Q. At this time, the outer peripheral surfaces of the base end side pins F2 press the front surfaces 2a1, 2a2 of the base member 2 and the front surface 5a of the cover plate 5 and perform friction stir, so that the plastic fluidizing material can be reliably pressed into and filled into the void Q. By flowing the plastic fluidizing material into the void Q to fill the periphery of the heat medium tube 6 with metal, the water tightness and air tightness of the heat transfer plate 1B can be further improved.
According to the method of manufacturing the heat transfer plate of the present embodiment, substantially the same effects as those of the first embodiment can be obtained. Further, the heat transfer plate 1B including the heat medium pipe 6 can be easily manufactured.
Further, for example, the shapes of the groove 3, the lid groove 4, the lid plate 5, and the heat medium pipe 6 of the first and second embodiments are only examples, and other shapes are also possible.
(symbol description)
1. 1A, 1B heat transfer plates;
2. a base member;
3. a groove;
4. a cover groove;
5. a cover plate;
6. a tube for a heat medium;
f main joining rotary tool (rotary tool);
f2 A base end side pin;
f3 A front end side pin;
FD temporary bonding rotation tool;
a J1 and J2 butt joint part;
w, W1 plasticized regions;
SP1, SP2 start position;
EP1, EP2 end positions;
s1, S2 middle points.