JP2003191081A - Friction stirring and joining device, and method for setting joining condition of friction stirring and joining device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the convenience of a friction stirring and joining device. <P>SOLUTION: An arithmetic unit 71 is connected to a control device 72 to control a friction stirring and joining device body 73. The arithmetic unit 71 receives the input of a joining factor by a user, and the joining condition is transmitted to the control device 72 if the corresponding joining condition is included in the joining database. If the joining condition is not included in the joining database, the joining condition is automatically generated based on the joining factors and the information of a work corresponding to the information included in the joining factors. The joining condition is formed in the joining database according to the joining result received by the user. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a technique for joining materials to be joined by a friction stir welding method.

[0002]

2. Description of the Related Art In WO 93/10935, a tool (hereinafter referred to as a rotary tool) provided with a pin-shaped probe protruding from an end surface of a cylindrical member made of a material harder than a material to be bonded is rotated while being rotated. A friction stir welding method is described in which the material to be welded is joined by frictional heat generated between the rotary tool and the material to be welded by being inserted into the joint of the material to be welded and moved. This friction stir welding method uses the plastic flow phenomenon caused by the rotation and movement of the rotary tool by softening the welded material due to the frictional heat between the rotary tool and the welded material. How to do, for example,
It is based on a principle different from arc welding.

As described above, the friction stir welding method utilizes the phenomenon that the material to be welded is softened by the frictional heat between the rotary tool and the material to be welded. The degree of this softening has a great influence on the quality of the joint. If the material to be joined is not sufficiently softened, plastic flow of the material is unlikely to occur. Therefore, the flow of the material cannot catch up with the rotation / movement of the rotary tool, and an unfilled portion of the material is generated, and this portion becomes a bonding defect. On the contrary, when the material to be welded is excessively softened, slippage occurs between the rotary tool and the material to be welded, and the shearing force does not act. For this reason, the flow of the materials to be joined becomes insufficient, which also leads to the generation of unfilled portions.

From the above, in the friction stir welding method, it is important to control the welding conditions so that the materials to be welded have an appropriate degree of softening. WO 00/0270
4 describes a method of controlling the joining condition by controlling the operation of the head unit including the rotary tool based on two pieces of information, the load applied to the rotary tool and the position of the rotary tool.

[0005]

As described above, in the friction stir welding method, it is important to control the softening degree of the materials to be welded to an appropriate state in order not to deteriorate the quality of the welded portion. By the way, the relationship between the degree of softening, the plastic flow and the temperature usually differs depending on the material of the material to be joined. In addition, even with the same material, the amount of heat input to the materials to be welded varies depending on the dimensions of the rotary tool, the number of revolutions, the welding (moving) speed, etc., so the above relationships differ. further,
Even if the materials to be welded, the dimensions of the rotary tool, the number of revolutions, the welding speed, etc. are the same, if the shapes and dimensions of the materials to be welded differ, the diffusion state of heat will also differ, so the relationship will also differ .

Therefore, in order to properly determine the joining conditions, it is necessary to consider the above various joining factors. Here, it is also possible to derive the joining condition from various joining factors by numerical calculation or the like. However, establishing such a physical model is not easy. Therefore, for example, when joining data (relationship between joining factors and joining conditions) used at the time of joining is accumulated and new joining is performed, from the joining data accumulated so far,
It is considered that the method of estimating the proper joining conditions for the joining factor in this joining is a realistic and reliable method.

However, it takes a lot of time and labor to accumulate the joining data. For this reason, even if the joining devices having the same performance are used, there is a difference in the performance actually exhibited between the user who has accumulated a lot of joining data and the user who has accumulated little joining data.

In general, the operation of the joining apparatus is generally controlled by a dedicated control program incorporated in this apparatus. Even with the same welding device, by updating to a control program that employs a higher-performance algorithm, it becomes possible to join workpieces with a more complicated three-dimensional shape, which was not possible until now.

Here, when the control program is updated via a recording medium such as an FD, for example, the recording medium is obtained from the manufacturer of the bonding apparatus, transported, and the update recorded on this is carried out. It is necessary to incorporate such a control program into the control system of the joining device. Therefore, interposing the recording medium is inefficient in terms of physical distribution and time.

The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the usability of the friction stir welding apparatus. Specifically, in order to eliminate the difference in actual performance between users, when the user inputs the joining factor, the joining condition is automatically obtained. Further, the control program can be updated without interposing a recording medium.

[0011]

In order to solve the above problems, a friction stir welding apparatus according to the present invention comprises a friction stir welding apparatus main body, and a controller for controlling the friction friction stir welding apparatus main body according to welding conditions. An arithmetic unit for transmitting the joining condition to the control unit.

[0012] Then, the arithmetic unit, a joining database in which joining conditions are registered in association with joining factors,
The information about the material to be joined has a material database registered in association with the joining factor relating to the material to be joined, and means for accepting the joining factor from the user, and the joining factor accepted from the user is registered in the joining database. If this is the case, it is sent to the control device. On the other hand, if it is not registered in the joining database, the joining factor received from the user and the material to be joined included in this joining factor in the material database. The welding condition is calculated based on the information of the materials to be welded, which is associated with the welding factor related to, and is transmitted to the control device.

Here, the arithmetic unit connects to a predetermined server via a network, obtains a control program from the server, and updates the control program of the control unit with the control program obtained from the server. But it is okay.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 is a schematic view of a friction stir welding apparatus to which an embodiment of the present invention is applied.

As shown in the figure, the friction stir welding apparatus of this embodiment has a computing unit 71, a control unit 72, and a friction stir welding apparatus main body 73. Here, the arithmetic unit 71
A signal cable 74 is connected between the control device 72 and the control device 72. In addition, the control device 72 and the friction stir welding device main body 7
A signal cable 75 is connected between the signal lines 3 and 3.

In the above structure, the arithmetic unit 71 accepts various joining factors (material, shape and size of the material to be joined, dimensions of the rotary tool, number of revolutions and joining speed, etc.) from the user, and the accepted joining factors are used. Calculate suitable joining conditions. Then, the calculated joining condition is transmitted to the control device 72 via the signal cable 74. The control device 72 transmits control information to the friction stir welding device main body 73 via the signal cable 75. As a result, the friction stir welding apparatus main body 7
The operation of No. 3 is controlled according to the joining condition received from the arithmetic unit 71 via the signal cable 74.

Next, the arithmetic unit 71 will be described in more detail. As the control device 72 and the friction stir welding apparatus main body 73, those of the existing friction stir welding apparatus can be used as they are, and therefore detailed description thereof will be omitted here.

The arithmetic unit 71 includes a CPU, a memory functioning as a work area of the CPU, an external storage device such as an HD, an input device such as a keyboard and a mouse, an output device such as a display and a printer, and a CD-ROM. A reading device for reading information from a storage medium such as a control device IF for communicating with the control device 72 via a signal cable 74.
And a bus for interconnecting these devices, a general computer system is realized by the CPU executing a predetermined program loaded in the memory.

Here, the predetermined program is read from a storage medium such as a CD-ROM by a reading device or downloaded from a network via a network IF (not shown) and temporarily stored in an external storage device. And then loaded into memory. Alternatively, it is loaded directly into memory.

FIG. 2 is a diagram for explaining the operation flow of the arithmetic unit 71 shown in FIG.

First, when various welding factors (information including material, shape and size of material to be welded, size of rotating tool, rotation speed and welding speed) are input by the user via the input device (S201). ), The arithmetic unit 71 predetermines the input joining factor from the joining data (data indicating the relation between the joining factor and the joining condition) registered in advance in the joining database formed in the external storage device or the like. Bonding data that matches the specified criteria or more is searched (S202). For example, the joining data in which the materials and shapes of the materials to be joined are the same and the difference from other joining factors is within several percent is searched.

When such joining data can be detected (Yes in S202a), the joining conditions included in the joining data are output to the output device, and the joining condition is corrected by the user via the input device. An instruction as to whether or not to add is received (S206). On the other hand, if such joining data cannot be detected (No in S202a), based on the input joining factor and various information registered in advance in the material database formed in the external storage device or the like, The joining condition for the joining factor is calculated (S203), and this is output from the output device (S204).

Next, the arithmetic unit 71 determines whether or not the calculated welding conditions are appropriate for the control unit 72 and the friction stir welding apparatus main body 73 which constitute the friction stir welding apparatus together with the present arithmetic unit 71, that is, It is determined whether or not the operation that the calculated welding condition complies with exceeds the capabilities of the control device 72 and the friction stir welding device main body 73 (S205).

When it is determined in S205 that the calculated joining condition is proper, the arithmetic unit 71 outputs a message to that effect from the output device, and the user corrects the joining condition through the input device. An instruction of whether or not is accepted (S206).

When the instruction not to modify the joining condition is received, the joining condition calculated in S203 is transmitted to the control device 72 via the signal cable 74 (S210). On the other hand, when the instruction to modify the joining condition is received, the input of the corrected joining condition is received from the user via the input device (S207), and the corrected joining condition is sent via the signal cable 74. And transmits it to the control device 72 (S210).

If it is not determined in S205 that the calculated joining condition is proper, the arithmetic unit 7
No. 1 outputs a message to that effect from the output device, and accepts an instruction from the user via the input device as to whether or not to manually set the joining conditions (S208). As a result, when the user gives an instruction to manually set the joining condition, the input of the joining condition is accepted from the user via the input device (S
209), the input joining conditions are changed to the signal cable 7
4 to the control device 72 (S210). In S208, if the user does not instruct to manually set the joining condition, the arithmetic device 71 ends the process without transmitting the joining condition to the control device 72.

Now, the control device 72 has a signal cable 74.
When the welding condition is received from the arithmetic unit 71 via the, the control information is transmitted to the friction stir welding apparatus main body 73 via the signal cable 75. As a result, the friction stir welding apparatus main body 7
The operation of No. 3 is controlled according to the received joining condition (S2
11). Then, when the operation of the friction stir welding apparatus main body 73 according to the welding conditions is completed, the fact is notified to the arithmetic unit 71 via the signal cable 74.

When the arithmetic unit 71 receives the operation completion notice of the friction stir welding apparatus main body 73 from the control unit 72 via the signal cable 74, the arithmetic unit 71 outputs a message to that effect from the output unit and the user from the input unit. The evaluation of the joining result is accepted (S212). Specifically, the user receives a determination as to whether the joining condition transmitted in S210 is worth registering in the joining database as joining data together with the joining factor accepted by the user in S201.

As a result, if the evaluation result that is worth registering is received from the user (Yes in S213).
s), the joining data including the joining condition transmitted in S210 and the joining factor accepted by the user in S201 is registered in the joining database (S214), and then the process ends. On the other hand, if the evaluation result indicating that it is not worth registering is received from the user (No in S213), the process is ended as it is.

Next, the processing in S203 of the flow shown in FIG. 2 (processing for calculating the joining condition from the inputted joining factor)
Will be described in more detail. FIG. 3 shows S20 of FIG.
It is a figure for demonstrating the operation | movement flow of FIG.

First, the arithmetic unit 71 collects information such as the material, shape and size of the material to be joined, which is input as a joining factor by the user, and the information registered in the material database in association with these pieces of information. An appropriate value ko of the deformation resistance is calculated using the predetermined rule (S301).

Next, the arithmetic unit 71 sets the rotational speed N of the rotary tool to a temporary value (S302), and uses this rotational speed N and the information input as the welding factor by the user to determine the joint portion. The temperature and the strain rate (welding rate) of the joint are calculated (S303).

Here, the temperature of the joint can be calculated by the following equation 1.

[0035]

[Equation 1]

The strain rate of the joint can be calculated by the following equation 2.

[0037]

[Equation 2]

In these equations, A is the size and shape of the rotary tool, B is the size and shape of the joining material, and λ
Is the thermal conductivity of the bonding material, Cp is the specific heat of the bonding material, and ρ
Is the density of the bonding material. These are information input as joining factors by the user.

Next, the arithmetic unit 71 responds to the temperature and strain rate of the joint portion calculated as described above and the information such as the material, shape and size of the material to be joined which is input by the user as the joining factor. The deformation resistance value kc at the bonded portion of the bonding material is calculated using the information attached and registered in the material database (S304).

Here, the deformation resistance value k at the joining portion of the joining material
c can be calculated by the following Expression 3.

[0041]

[Equation 3]

In equation 3, Q is the apparent activation energy, C is the material coefficient determined by the material,
This is the information registered in the material database. R is a gas constant.

Next, the arithmetic unit 71 compares the appropriate value ko of the deformation resistance calculated as described above with the deformation resistance value kc at the joining portion of the joining material (S305).

As a result, if the deformation resistance value kc is equal to or less than the appropriate value ko, various conditions (rotational speed of the rotary tool, strain rate of the joint, etc.) used for calculating the deformation resistance value kc are The joining condition is set for the joining factor input by the user (S306). On the other hand, the deformation resistance value kc
If is larger than the appropriate value ko, various conditions are changed and an attempt is made to recalculate the deformation resistance value kc.

That is, first, the number of rotations N of the rotary tool is corrected to increase (S307). If the corrected rotation speed N is within the capability range of the friction stir welding apparatus main body 73 (No in S308), the deformation resistance value kc is calculated using the corrected rotation speed N (S303, S30).
4). On the other hand, if the corrected rotational speed N exceeds the capability range of the friction stir welding apparatus main body 73 (Yes in S308).
s), the number of rotations N is returned to before correction. Then, for example, it is checked whether or not a predetermined rule permits a change in the strain rate of the joint, and if it permits (Yes in S309).
s), the strain rate of the joint is corrected to decrease (S)
310). If the corrected strain rate of the joint is within the capability range of the friction stir welding apparatus main body 73 (S3
No. 11), the deformation resistance value kc is calculated using the corrected strain rate of the joint (S303, S304).

If the predetermined rule does not permit the change in the strain rate of the joint (N in S309).
o) or when the corrected strain rate of the joint exceeds the capability range of the friction stir welding main body 73 (S3)
No in 11), the arithmetic unit 71 ends the process without calculating the joining condition (S312). In this case, in S204 of FIG. 2, the arithmetic unit 71 outputs a message that the joining condition could not be calculated, and the process ends the flow shown in FIG.

Next, the material database used by the arithmetic unit 71 will be described. FIG. 4 is a diagram showing a data configuration example of the material database. In FIG. 4, the material, the form of the joint, the shape factor, and the dimensional factor correspond to the joining factor 401. 5 to 8 conceptually show four joining modes, that is, butt joining, lap joining, different thickness material joining, and L-shaped joining.

Here, reference numeral 101 is a material to be joined, and reference numeral 100 is a joining portion. The shape factor is a factor determined according to the joining form. The dimensional coefficient is a coefficient determined according to the size of the joint. The material coefficient, the deformation resistance reference value, and the activation energy registered in association with these joining factors 401 are the appropriate value ko of the deformation resistance and the deformation of the joining material at the joining portion in the flow shown in FIG. Resistance value k
It is used to calculate c and. For example, the appropriate value ko of the deformation resistance corresponds to the deformation resistance reference value under the selected specific condition. In this case, since the deformation resistance reference value differs depending on the bonding material, the appropriate value ko of the deformation resistance also has a different value for each material. Further, as shown in Expression 3, the deformation resistance value kc is a function of temperature and strain rate, and the value at the joint changes depending on the rotation speed and shape of the rotary tool. In the flow shown in FIG. 3, the deformation resistance value kc is predicted by calculation, and the joining condition is optimized so that the value is close to the appropriate value ko of the deformation resistance.

Next, the joining database used by the arithmetic unit 71 will be described. FIG. 9 is a diagram showing a data configuration example of the joining database. In the flow shown in FIG. 2, when an evaluation result indicating that it is worth registering is received from the user (Yes in S213), the bonding including the bonding factor 901 received from the user in S201 and the bonding condition 902 transmitted in S210. A new record 903 composed of data is added to the joining database (S21).
4).

The present inventors conducted an experiment of butt-joining 5 mm thick A5052 material using the friction stir welding apparatus of this embodiment. As a result of inputting this condition to the arithmetic unit 71, as a welding condition, a welding speed of 300 (mm /
Min) and a rotation speed of 800 (rev / min) was obtained. As a result of joining without modifying the joining conditions, it was possible to obtain a joined portion having no defects on the surface and inside. Therefore, the present invention decides to register the joining data including the joining factor and the joining condition at this time in the joining database. Furthermore, the present inventors have shown that the welding speed is 30% for comparison.
0 (mm / min) is left unchanged, and the rotation speed is 400 (rotation /
Min) and tried joining. As a result, surface defects occurred. Therefore, the joining data consisting of the joining factors and joining conditions at this time was discarded without being registered in the joining database.

The embodiment of the present invention has been described above.

In the present embodiment, when the joining condition corresponding to the joining factor input by the user is stored in the joining database as a database, the user can join the materials to be joined under this joining condition. That is, by using the database provided in the arithmetic device 71, it is possible to eliminate the performance difference that is actually exhibited among the individual users who use the friction stir welding apparatus of the present embodiment.

Further, according to the present embodiment, when the joining condition corresponding to the joining factor inputted by itself is not stored in the database, this joining factor and the information contained in this joining factor in the material database are dealt with. It is possible to automatically generate a joining condition based on the attached information of the joined members and to join the joined members by using the joining conditions.
Then, according to the joining result, the joining condition can be stored in the joining database. By doing so, the welding results performed by the individual users who use the friction stir welding apparatus of the present embodiment can be reflected in the welding database, and thus the friction stir welding apparatus can have learning ability. , The performance actually exhibited can be further improved.

As described above, according to the present embodiment, the usability of the friction stir welding apparatus can be improved.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the gist thereof.

For example, although not described in detail in the above embodiment, the shape and dimensions of the rotary tool are also included as items to be added as joining conditions. Further, the rotation speed determined by the arithmetic unit 71 also takes into consideration the rotation direction. That is, the rotational speed is a numerical value with a sign, and if the absolute values are the same but the signs are different, it means that the rotational directions are opposite.

Further, as shown in FIG. 10, the arithmetic unit 71 which constitutes the friction stir welding apparatus of the above-mentioned embodiment uses a network 80 such as a public line network or a dedicated line network,
The control program update server 81 may be connectable. Then, a function of downloading the latest control program stored in the control program update server 81 and updating the control program of the control device 72 connected to itself may be added to the arithmetic device 71. By doing so, the arithmetic device 71 can update the control program of the control device 72 to the latest control program without interposing a recording medium.

Note that, in FIG. 10, the control program update server 81 may be configured to function as a relay device that relays communication between the arithmetic devices 71. By doing so, the arithmetic device 71 can also exchange information with another arithmetic device 71 and incorporate the contents of the junction database of the other arithmetic device 71 into its own junction database. . This provides advantages such as reduced risk for unknown joining conditions.

[0059]

As described above, according to the present invention,
The usability of the friction stir welding apparatus can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view of a friction stir welding apparatus to which an embodiment of the present invention is applied.

FIG. 2 is a diagram for explaining an operation flow of the arithmetic unit 71 shown in FIG.

FIG. 3 is a diagram for explaining an operation flow of the arithmetic unit 71 shown in FIG.

FIG. 4 is a diagram showing a data configuration example of a material database used in the present embodiment.

FIG. 5 is a conceptual diagram of butt joining.

FIG. 6 is a conceptual diagram of lap joining.

FIG. 7 is a conceptual diagram when joining materials having different thicknesses.

FIG. 8 is a conceptual diagram of L-shaped joint joining.

FIG. 9 is a diagram showing a data configuration example of a joining database used in this embodiment.

10 is a conceptual diagram of a network system when the arithmetic unit 71 shown in FIG. 1 is provided with a control program updating function.

[Explanation of symbols]

71 ... Arithmetic device, 72 ... Control device, 73 ... Friction stir welding device, 74, 75 ... Communication cable, 80 ... Network, 81 ... Update program providing server, 101 ... Joined material

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenji Araki             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Hisanobu Okamura             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. F-term (reference) 4E067 BG00 CA01 CA05

Claims (6)

[Claims] 1. A friction stir welding apparatus for joining a material to be welded by inserting and moving the rotating tool into a welding portion of the material to be welded, the friction stir welding apparatus main body, and a friction stir welding apparatus according to a welding condition. A controller for controlling the main body of the friction-friction stir welding apparatus, and an arithmetic unit for transmitting a welding condition to the controller, wherein the arithmetic unit is a welding unit in which welding conditions are registered in association with welding factors. A database, information about the material to be joined, a material database registered in association with the joining factor related to the material to be joined, and means for receiving the joining factor from the user, the joining factor received from the user is the If it is registered in the bonding database, it is sent to the control device, while if it is not registered in the bonding database, it is accepted by the user. The joining condition is calculated based on the joining factor and the information of the joining material associated with the joining factor related to the joining material included in the joining factor in the material database, and the joining condition is calculated by the controller. The friction stir welding device is characterized in that it is transmitted to. 2. The friction stir welding apparatus according to claim 1, wherein the computing device, in accordance with an instruction from a user, associates the welding condition transmitted to the control device with a welding factor received from the user,
A friction stir welding device characterized by being registered in the welding database. 3. The friction stir welding apparatus according to claim 1, wherein the arithmetic unit is connected to a predetermined server via a network, obtains a control program from the server, and operates the control unit. A friction stir welding apparatus, wherein the control program is updated to the control program obtained from the server. 4. The friction stir welding apparatus according to claim 1, 2 or 3, wherein the welding factor includes a material, a shape, a dimension and a welding mode of the materials to be welded, and the welding condition is the rotation speed of the rotary tool. And a friction stir welding apparatus including a welding (moving) speed. 5. A welding condition setting method for a friction stir welding apparatus, in which a rotary tool is inserted into a joint portion of a material to be welded while rotating and is moved to weld the material to be welded. A friction stir welding apparatus main body, a controller that controls the friction friction stir welding apparatus main body in accordance with the welding conditions, and an arithmetic unit that transmits the welding conditions to the control unit. A step of accepting a factor, and if the accepted joining factor is registered in a joining database in which the joining conditions are associated with the joining factor, the step of transmitting the corresponding joining condition to the control device. And if the accepted joining factor is not registered in the joining database, the accepted joining factor and information about the material to be joined are joined. In the material database registered in association with the joining factor related to the welding condition, based on the information about the joined material associated with the joining factor related to the joined material included in the accepted joining factor, And a step of transmitting the calculated value to the control device, the welding condition setting method for the friction stir welding device. 6. A program for setting a welding condition of a friction stir welding apparatus for welding a welding material by inserting the welding tool into a welding portion of a welding material while rotating the rotating tool and moving the friction tool. The stir welding apparatus includes a friction stir welding apparatus main body, a control device that controls the friction friction stir welding apparatus main body according to welding conditions, and an arithmetic device that transmits welding conditions to the control device, and the program is, The step of accepting a joining factor from the user to the computing device, and if the accepted joining factor is registered in a joining database in which joining conditions are associated with joining factors, the corresponding joining conditions To the control device, and if the accepted joining factor is not registered in the joining database, the accepted joining In the material database in which the child and the information about the material to be joined are associated with the joining factors related to the material to be joined, and are associated with the joining factors relating to the material to be joined included in the accepted joining factors. A program for executing a joining condition based on information about the materials to be joined and transmitting the joining condition to the control device.