JPS5857482B2 - sintering equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for sintering a sintered body formed by press-molding powder or the like, and in particular, a device for sintering a sintered body formed into a long shape continuously or intermittently. Conventionally, sintering is carried out by sequentially feeding and heating and pressurizing at the same time.For example, there is a method for continuously sintering a long material using a hot press that simultaneously heats and pressurizes. As disclosed in Japanese Patent No. 45-7406, a sintered body made of powder formed into a thin plate is guided between a pair of sintering rollers, and the sintered body is energized through the rollers. It is known that it can be sintered.

However, in this method of sintering with electricity while passing between rollers, heating and pressure are applied locally, so long sheets with large thickness (relatively large cross-sectional area) It is difficult to efficiently sinter the powder to be sintered, and in the case of electric sintering, if the powder is compacted too densely, the electrical resistance between the powders decreases and the sintering material becomes difficult to sinter. Heating means using electrical heating is not suitable for high-density sintering because the heat generation in the body part is reduced and the proportion of heat generation in other parts of the circuit increases, resulting in a deterioration of energy efficiency.

In view of these points, the present invention is proposed for the purpose of efficiently sintering long members having a relatively large cross-sectional area and high-density objects to be sintered with low energy loss.

pressurizing heads disposed opposite to each other with a gap sandwiching the object to be sintered, and at least one of the opposing pressurizing heads being movable in the opposing direction; A driving device for moving the pressurizing head in opposing directions; a moving device for relatively moving the sintered body and the pressurizing head positioned between the pressurizing heads in a direction orthogonal to the opposing direction; The device is characterized in that it comprises a coil that can be rotated, and a high frequency power source connected to the coil.

The present invention will be explained below with reference to an embodiment of the drawings.

In FIG. 1, reference numeral 1 denotes a pressure head, which is vertically symmetrically provided with the object to be sintered in between.

Inside the head, the high frequency coil 2 is made of heat-resistant material MtOtA.
It is placed in heat-resistant oxide powder 3 such as T20A, solidified and loaded, and a heat-resistant member 4 such as graphite or SiC is fixed at the tip to cover this, and a consumable material is provided at the contact part with the object to be sintered. A sheet 5 of the product is interposed.

Reference numeral 6 denotes a lead wire connected to a driving device for a pressure head consisting of a pressure cylinder or the like, and 1 a lead wire connected to a high frequency power source.

Reference numeral 8 denotes a rod-shaped or band-shaped elongated material to be sintered, which is, for example, a bonded compact of powder in the case of powder sintering, a bonding material for a powder compact and a cast body, a mixed material, etc.

9 is a moving device (not shown) that supports both ends of the object to be sintered 8;
With the chuck, the object 8 to be sintered is firmly supported and moved in the direction of the horizontal arrow to provide relative movement between it and the pressure head 1.

For example, a moving device using a cylinder, a rack and pinion, or a crank mechanism may be arbitrarily provided.

The device for moving the object 8 to be sintered in order to move it relative to the pressure head 1 can be of various configurations as described above, but the movement is continuous or intermittently. It can be moved intermittently or intermittently, and any method can be adopted depending on the purpose of sintering.

If the movement is carried out continuously, the entire object 8 to be sintered, which is a long member, can be sintered one part at a time, and if it is moved intermittently, it can be sintered partially, and the sintered part and the unsintered part can be separated. When a certain sintered body is obtained and sinter welding is performed, this intermittent movement has the effect of efficiently sintering only the sinter welded part.

Sintering is performed by pressurizing a part of the body 8 to be sintered using the pressure head 1.

As shown in the figure, the pressurizing heads may press both vertically opposed heads with the object 8 to be sintered in between, or press one side, for example, the lower head, while the upper head is fixed. You can also pressurize it by itself.

Of course, the fixed lower head can also be constructed of something like a processing table.

Further, the pressurizing heads can be provided laterally in the left and right directions, sandwiching the object 8 to be sintered, and furthermore, any number of pressure heads can be provided facing each other in any direction around the object 8 to be sintered.

By supplying a high frequency current from a high frequency power supply to the coil 2 to the pressurized portion of the body 8 to be sintered by the pressure head 1,
Eddy currents are generated by electromagnetic induction, and the object to be sintered is heated by so-called high-frequency heating due to this eddy current.
Sintering is performed by pressing in a heated hot state.

A consumable sheet 5 is interposed at the tip of the pressure head 1, and this sheet is made of, for example, a thin film formed by kneading metal powder, heat-resistant powder, lubricating powder, etc. with resin or the like. The separating action and lubricating action of this sheet prevent the head 1 and the object to be sintered 8 from welding together, and the lubricating effect makes it possible to easily move the object to be sintered, allowing for sequential and stable sintering. can be done.

Since the sheet 5 is a consumable item and is easily torn, it can be continuously supplied from a winding bobbin to the gap as the body 8 to be sintered moves.

Alternatively, the surface of the body 80 to be sintered may be covered in advance.

In other embodiments, instead of this sheet, or in addition to using the sheet, a heat-resistant powder can be used, a gas such as an inert gas can be ejected, and in some cases, a reactive gas can be used, and any combination can be used. can.

When the object to be sintered 8 is moved intermittently or intermittently, the pressure head 1 is operated in synchronization with this movement, the pressure is released during movement, and the object to be sintered is pulled upward. Continuous and stable sintering can be achieved by automatically controlling the process to press, heat, and sinter when the machine stops moving.

It is also possible to control the sequence of sintering and movement.

FIG. 2 shows an embodiment in which a large number of small objects are successively sintered as objects to be sintered, and the same reference numerals as in FIG. 1 indicate the same parts.

Reference numeral 13 denotes a molded heat-resistant material in which filled portions of powder to be sintered having a desired shape are provided at predetermined intervals, and sintered powder 14 is filled into the holes filled with the shape.

15 is a head for pressing the powder 14;

In the embodiment shown in FIG. 2, a heating means is also provided by directly applying electricity to the object 14 to be sintered, and a pulse power source, a DC + AC (high frequency) power source, an AC power source, etc. are connected to the terminal 12, and thereby, The object to be sintered 14 is preheated by electrical heating.

In this case, the molded heat-resistant material 13 also serves as a current-carrying electrode, and the filling powder 1
Step 4: Conduct electrical heating.

The filling powder 14 is preformed by this electrical heating and pressure by the press head 15, moves and flows into the pressure head 1 for sintering, and is then subjected to high frequency heating for sintering and Pressing is performed and sintering is performed by hot pressing.

Synchronize the operation of the head 1 and the movement feed by the movement device,
By performing the movement intermittently and constantly feeding the object 14 to the pressurizing head 1, sintering is performed sequentially, and a large number of sintered products can be sintered in succession. .

Note that when filling the molded heat-resistant material 13 with the powder 14, if a consumable sheet is interposed in between, the fired crystals can be easily taken out.

FIG. 3 is a top view of the objects to be sintered which are successively sintered.

Note that sintering and welding can be performed using the sintering apparatus having the configuration shown in FIG.

When performing welding, the member 13 in the figure may be replaced with a welding member to be welded together, and sintering powder may be filled between the welding members to integrally sinter-weld them.

This allows continuous sinter welding.

The sintering materials used include graphite, metals and their oxides, nitrides, carbides, and other compounds, as well as semiconductors, magnetism, and other materials that are electrically conductive or that become electrically conductive when heated. Capable of powder sintering, mixed sintering, sinter welding, and connecting and sintering of dissimilar materials.

As described above, according to the present invention, it is possible to efficiently sinter a long object to be sintered, and in particular, by equipping the pressure head driven in opposite directions with a high-frequency heating device,
Compared to the case where the object to be sintered is held under pressure between rollers and heated by electricity, it is possible to simultaneously heat and press a relatively wide area of the object to be sintered. The length member can also be sintered efficiently, and since the present invention uses high-frequency heating, high-density sintering can be easily and energy-efficiently performed.

[Brief explanation of the drawing]

FIG. 1 is a diagram of one embodiment of the present invention, FIG. 2 is a diagram of another embodiment,
FIG. 3 is a top view of the object to be sintered in the embodiment of FIG. 2. 1 is a pressure head, 2 is a high frequency coil, 4 is a heat-resistant member, 5
1 is a consumables sheet, 8 is a body to be sintered, 9 is a chuck of a moving device, 12 is an energizing power source connection terminal, 13 is a molded heat-resistant material, 14
1 is a sintered body, and 15 is a pressure head.

Claims (1)

[Claims] 1 Pressure heads disposed opposite to each other with a gap sandwiching the object to be sintered, and at least one of the opposed pressure heads being movable in the opposing direction; and the movable pressure head. a driving device that moves the pressurizing head in the opposing direction; a moving device that relatively moves the pressurizing head and the object to be sintered located between the opposing pressurizing heads in a direction perpendicular to the opposing direction; A sintering apparatus comprising: a coil provided on the pressure head; and a high frequency power source connected to the coil.