JPS5948712B2 - Dimension control method in diffusion welding - Google Patents

Description

[Detailed description of the invention] The present invention relates to a dimensional control method in diffusion welding.

Diffusion welding involves heating the welding material above the recrystallization temperature,
Welding is performed by diffusion of atoms under pressure in an atmosphere such as an inert gas, which may result in slight deformation.

As methods for controlling this dimension, so far, there have been "deformation amount control method in diffusion welding" (see Japanese Patent Application Laid-Open No. 51-20745) and "blade height dimension control method for diffusion welded impeller".
(Refer to Japanese Unexamined Patent Publication No. 125394/1983) has been proposed.

FIG. 1 is a schematic diagram for explaining the former control method, and FIGS. 2 and 3 are schematic diagrams for explaining the latter control method.

In Fig. 1, an electric equipment jig 1 is attached to a welded body 4 (4' is a welded part) or an intermediate member 3 such as ceramic (intermediate member 3 in the figure).
01 and 102 are installed and the electric circuit 10 is connected to them.
From the open circuit before welding in step 3, the welding of the welded body 4 progresses due to the pressurization of the pressure rod 1, and when the amount of deformation of the welded body 4 reaches a predetermined value, the transition point becomes a closed circuit. The signal at the time of this conversion is actuated to the pressurizing mechanism section 104, and the pressurizing rod 1
The amount of welding deformation of the welded body 4 is controlled by releasing the pressure applied to the welded body 4.

In addition, 2 in FIG. 1 is a pressure receiving stand. However, with this method, there is no problem when the welded body is small and the applied force is uniform and the welded body deforms uniformly, but when the welded body is large, the applied force becomes uneven and the welded body deforms unevenly. hand,
There is a drawback that accurate dimensional control of the entire welded body is difficult to perform.

(1) In Fig. 2, a stopper 105 is provided in the extra wall at the outer peripheral end of the impeller, having an area equal to or larger than the blade welding area, and having a height equal to the required blade height. The height of the blade is controlled by applying pressure while sandwiching it between ceramic or graphite intermediate members 3, and releasing the pressure by capturing the displacement point of the pushing displacement of the pressurizing rod 1 at the welding position. 2) In Figure 3, 1 part of the welding area of each blade is attached to the outer periphery of the impeller and the part where the rotor shaft is inserted.
Ceramic or graphite having an area of /2 or more and whose height is set to the required blade height considering the thermal expansion difference with the impeller material during heating is set as the stopper 105A, and the top and bottom are made of ceramic or graphite. The height of the blade is controlled by applying pressure while being sandwiched between the intermediate members 3 and releasing the pressure based on the displacement point of the pushing displacement of the pressurizing rod 1 at the welding position. In addition,
In Figures 2 and 3, the same reference numerals as in Figure 1 indicate the same functional parts as in Figure 1, 41 is the lower plate of the impeller, 42 is the same upper plate, 4
In this case, 3 is a blade cut out from the same plate 42, and 4'' is a welded part.However, in the method shown in FIG.
Since the stopper 105 must be machined for each welded body, there is a disadvantage that material costs, processing costs, and man-hours increase.Furthermore, in both methods shown in Figs. 2 and 3, the welded body is large and the pressing force is high. If it is not uniform, the amount of deformation will be uneven and the point of displacement of the pressurizing rod will not clearly appear, and there will be disadvantages such as the inability to detect parts that have reached a predetermined dimension and parts that have not. be.

Therefore, currently, when the deformation of the welded body progresses unevenly,
The parts that have reached a predetermined amount of deformation and the parts that have not reached a predetermined amount of deformation are detected, and the portions that have reached a predetermined amount of deformation are prevented from further deformation, and only the portions that have not reached the predetermined amount of deformation are allowed to deform. There is a need for uniform dimensional control throughout.

The present invention was made to meet this need.
A plurality of limit plates are installed to prevent the welded body from deforming by more than a predetermined amount of deformation, and an electric circuit for detecting the amount of deformation provided between the limit plates and the intermediate member determines when a fellow member comes into contact with the limit plate. The welded body is pressurized and released after the welded body comes into contact with all the limit plates, thereby controlling the dimensions of the entire welded body uniformly.The gist of the present invention is as follows: be.

(1) In diffusion welding, a limit plate made of an insulator material and a conductor material that is smaller in height than the welded body and has high strength at high temperatures is used, and the limit plate is placed on the lower intermediate member as an insulator. Two or more limit plates are installed so that the material side is in contact with the lower intermediate member, and an electric circuit is provided on the upper intermediate member and the conductive material side of each limit plate to detect the amount of deformation of the welded body. When the deformation progresses and the upper intermediate member and the conductive material side of the limit plate come into close contact, the welded body deformation amount detection circuit becomes a closed circuit,
A dimensional control method in diffusion welding (this is referred to as the first invention), characterized in that pressure is released after all of the welded body deformation detection circuits of each limit plate become closed circuits.

(2) In diffusion welding, a limit plate made of a conductive material that is smaller in height than the welded body and has high strength at high temperatures is used, and a conductive material that has high strength at high temperatures is used as the upper intermediate member. An insulating material having high temperature and high strength is used as the side intermediate members, two or more limit plates are installed on the lower intermediate member, and the amount of deformation of the welded body is detected on the upper intermediate member and each limit plate. When the deformation of the welded body progresses during diffusion welding and the upper intermediate member and limit plate come into close contact, the welded body deformation detection circuit becomes a closed circuit, and the welding of each limit plate is completed. A dimensional control method in diffusion welding characterized in that pressure is released after all body deformation amount detection circuits become closed circuits (this is referred to as a second invention).

Hereinafter, the first and second inventions will be explained in detail using the accompanying drawings.

4 to 6 are explanatory diagrams showing an example of an embodiment of the first invention,
Figure 4 shows the state before diffusion welding, Figure 5 shows the state when the deformation of the welded body progresses unevenly during diffusion welding, and Figure 6 shows the state after diffusion welding, where the entire welded body is uniformly deformed. It is a figure which shows the state where size control was carried out.

In Figures 4 to 6, the same symbols as in Figures 1 to 3 refer to 1 to 3.
The same functional product as shown in the figure is shown, and the upper intermediate member 3 may be made of a conductor having high strength at high temperature such as graphite, and the lower intermediate member 3'' may be made of either a conductor or an insulator as long as it has high strength at high temperature.

5-1 and 5-2 are conductive materials having high temperature and high strength such as graphite, 6-1 and 6-2 are insulating materials having high temperature and high strength such as ceramic, and the limit plate in the first invention is It consists of the conductor material 5-1 (or 5-2) and the insulator material 6-1 (or 6-2) (hereinafter, the conductor material will be referred to as a conductor limit plate,
The insulator material is called an insulator limit plate).

7-1, 7-2 are electrical cable fittings, 8-1, 8-2
is an electrical cable, and 9-1 and 9-2 are resistance meters.

First, each of these members is arranged as shown in FIG.
At this time, a gap having a dimension A is formed between the upper intermediate member 3 and the conductor limit plate.

This gap A becomes the amount by which the size of the welded body 4 is reduced by diffusion welding until it reaches a predetermined size. This gap dimension A is calculated based on the design deformation rate of the welded body 4 and the coefficient of thermal expansion of the welded body 4 and each limit plate, and the total height dimension of the insulator limit plate and the conductive limit plate is calculated from the welded body 4. This is achieved by making the height dimension A smaller than the height dimension of 4. Note that in the state shown in FIG. 4, the welded body deformation amount detection circuit provided in the upper intermediate member 3 and each conductor limit plate 5-1, 5-2 is an open circuit, so the detection circuit Each of the resistance meters 9-1 and 9-2 provided therein indicates 1Ω. When the deformation of the welded body 4 progresses unevenly during diffusion welding and only the conductor limit plate 5-1 comes into close contact with the upper intermediate member 3, as shown in FIG. 5-1 and the welded body deformation detection circuit of the upper intermediate member 3 become a closed circuit, and the resistance meter 9-1 shows OΩ, but the conductor limit plate 5-2 side which is not in close contact with the upper intermediate member 3 The welded body deformation detection circuit remains open circuit, and the resistance meter 9-2 remains at 1Ω.

When diffusion welding is further progressed from this state, the conductor limit plate 5-1 side of the welded body 4 is completely prevented from being deformed by the conductor limit plate 5-1, and the welded body 4 is
The deformation progresses only on the conductor limit plate 5-2 side,
Eventually, as shown in Fig. 6, the conductor limit plate 5-2 also comes into close contact with the upper intermediate member 3, and the welded body deformation detection circuit on this side becomes a closed circuit, and the resistance meter 9-2 is also connected. Indicates OΩ.

In this way, when all the welded body deformation detection circuits attached to the upper intermediate member 3 and the conductor limit plates 5-1 and 5-2 become closed circuits, the entire welded body 4 can be uniformly controlled in size. It is something that

In addition, in the first invention, each limit plate is used to detect the amount of deformation of the welded body as well as to prevent the deformation of the welded body as described above, so at least the welded body joint area is It is desirable to have an area of 1/2 or more. Further, in the first invention, the gap size A described above is calculated using the following formula.

However, L1; Height of the welded body Coefficient of thermal expansion γ of plate; Coefficient of thermal expansion of insulator limit plate The first invention described above has the following superior features compared to the method of the previously applied application.

(1) During diffusion welding, it is possible to detect areas where the conductive limit plate and the upper intermediate member are in close contact and areas where they are not in close contact, and the deformation of the welded body does not progress any further on the side where the conductive limit plate and the upper intermediate member are in close contact.
The deformation of the welded body progresses only on the side that is not in close contact, and diffusion welding is completed with all conductor limit plates and upper intermediate members in close contact, so the entire welded body can be welded uniformly and with high precision. Dimensions can be controlled.

(2) In the case of the same product, each limit plate can be used repeatedly, which is economical. (3) Since the amount of deformation of the welded body can be made constant, the properties and strength of the joint are guaranteed.

FIG. 7 is an explanatory diagram showing an embodiment of the second invention, and is a diagram showing the state of the diffusion welding agent.

In FIG. 7, the same reference numerals as in FIGS. 1 to 6 indicate the same functional parts as in FIGS. 1 to 6, the upper intermediate member 3 is made of the same conductor as the first invention, and the lower intermediate member 3'' is made of ceramic, etc. It is an insulator with high strength at high temperatures.

That is, in the second invention, the insulator limit plate in the first invention is omitted, and the lower intermediate member 3'' also has an insulating function.

The mode of action and effects of the second invention are completely the same as those of the first invention. In addition, in the second invention as well, it is desirable that the area of the limit plate is 1/2 or more of the welded body joining area as in the first invention.

Moreover, the gap dimension A in the second invention is calculated by the following formula.

However, the code in the formula is the gap dimension A in the first invention.
It has exactly the same meaning as the calculation formula.

[Brief explanation of drawings]

1 to 3 are explanatory diagrams showing a conventional dimensional control method in diffusion welding, FIGS. 4 to 6 are explanatory diagrams showing an example of an embodiment of the first invention, and FIG. 7 is an explanatory diagram showing an example of the embodiment of the first invention. FIG. 1 is an explanatory diagram showing an example of an embodiment of the invention.

Claims (1)

[Claims] 1. In diffusion welding, a limit plate made of an insulating material and a conductive material that is smaller than the welded body by a predetermined height and has high strength at high temperatures is used, and the limit plate is placed on the lower intermediate member. Two or more are installed so that the insulator material side is in contact with the lower intermediate member, and an electric circuit is installed on the upper intermediate member and the conductor material side of each limit plate to detect the amount of deformation of the welded body, and the welding is performed during diffusion welding. When the deformation of the body progresses and the upper intermediate member and the conductive material side of the limit plate come into close contact, the welded body deformation detection circuit becomes a closed circuit, and all of the welded body deformation detection circuits of each limit plate become closed circuits. A dimensional control method in diffusion welding that is characterized by releasing pressure after it has become . 2. In diffusion welding, a limit plate made of a conductive material that is smaller than the welded body by a predetermined height dimension and has high strength at high temperature is used as the upper intermediate member, and a conductive material that has high strength at high temperature is used as the lower intermediate member. Two or more limit plates are installed on the lower intermediate member, and an electric circuit for detecting the amount of deformation of the welded body is installed on the upper intermediate member and each limit plate. is provided, and when the deformation of the welded body progresses during diffusion welding and the upper intermediate member and the limit plate come into close contact, the welded body deformation amount detection circuit becomes a closed circuit, and the welded body deformation amount detection circuit of each limit plate is completely closed. A dimensional control method in diffusion welding characterized by releasing pressure after forming a closed circuit.