JPS6117936A - Forming method of tensile test piece of metallic material - Google Patents

Abstract

PURPOSE:To enable makihg a tensile test piece one by one from a thin steel sheet material by cutting the protruding part after clamping the raw material piece which was stamped out of a thin steel sheet material while giving a pretension between a pair of guide plates. CONSTITUTION:A tensile test piece automatic making line 1 is composed of the 1st cutting work station 4 and the 2nd cutting work station 5 providing the raw material piece feeding station 3 having a turner 7, fixed carrier 2, a clamp device 10 consisting of a pair of guide plates 12 and pusher device 9 and NC miller 11, and burr removing station 6, etc. The raw material piece W is then made larger than a tensile test piece P by stamping work from a thin steel sheet material, fed to No.1 work station 4 from the feeding station 3, clamped while giving a pretension between guide plates 12 and the protruding part is cut by the miller 11. Further performing the burr removal after the complete cutting at No.2 work station 5 the test piece P is made.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for making a tensile test piece of a metal material, particularly a steel plate material, and more particularly to a method of making a tensile test piece of a comparatively thin steel plate material.

BACKGROUND OF THE INVENTION At present, automatic tensile test systems that can automatically perform tensile tests on steel sheet materials are being researched.

If the tensile test is automatically performed by simply supplying Q'4-1 tensile test pieces, and the data processing is also performed automatically, the tensile test can be performed labor-savingly and can be connected to the production line. production management can be carried out efficiently.

Needless to say, in order to operate such an automatic tensile test system smoothly, it is also necessary to automate the preparation of tensile test pieces of such steel sheet materials. In order to easily automate the creation of such tensile test specimens, the method for creating tensile test specimens is to create tensile test specimens one by one from each rectangular steel plate base material. It is better to adopt a format that

The reason is that the test pieces are tested one by one.
If the test pieces can be made one by one, the test piece preparation and the tensile test can be performed in one process, making it possible to process them more efficiently in terms of time.

Therefore, it can be said that such a preparation method is most suitable for automating the preparation of tensile test pieces.

By the way, when creating a tensile test piece of a steel plate material to be subjected to a tensile test using such an automatic tensile test system, it goes without saying that the tensile test piece must comply with JIS standards (for example,
It must be manufactured in an efficient manner so as to satisfy the following requirements (dimensional accuracy, surface roughness, maintenance of mechanical properties of the steel sheet material base material, etc.). In addition, a tensile test piece of steel plate material consists of both wide ends and a narrow central band extending between the two ends, and in this case, the processing of the central band is one of the particularly important control points. Therefore, processing in that area must be done carefully.

In short, the preparation of such tensile test specimens needs to be carried out under predetermined processing conditions.

As is clear from the following description, in order to automate the preparation of tensile test specimens for steel plate materials so that the automatic tensile test system can operate smoothly, the above-mentioned preparation method must be followed under the predetermined processing conditions. This means that they must be hired.

Problems to be Solved by the Invention When a tensile test piece is prepared from a comparatively thick steel plate material base material, the double series does not pose a problem. This is because, in the case of a relatively thick steel plate base material, even if each piece is milled to create a tensile test piece one by one, the steel plate base material itself is solid, so the steel plate This is because there is less influence on the base material during processing.

On the other hand, in the case of a comparatively thin steel sheet material base material, it is not possible to create a tensile test piece in the same manner as in the case of a comparatively thick steel sheet material base material. This is because when tensile test specimens are created one by one by milling each relatively thin base steel sheet, large burrs are generated and negative effects such as residual distortion remain after processing. It is from, and also,
Particularly thin steel sheet material base material (e.g. 0.5 mm or less)
This is because when a sheet is milled, the base material of the steel sheet itself is damaged.

Therefore, conventionally, when creating a tensile test piece from a relatively thin steel sheet material base material, lot processing has been performed. That is, by stacking a plurality of thin steel plate material base materials and milling this stack, a plurality of tensile test specimens were created at one time.

However, such conventional preparation methods cannot automate the tensile test.

When performing lot processing as described above, it is necessary to stack a plurality of sheets of steel sheet material base material to form a stack, and to separate each sheet of the stack after processing. Needless to say, it is extremely difficult to automate this kind of work, and even if such automation were possible, it would require automatic identification marks for management on each specimen. The equipment cost would be very high since it would require additional equipment such as a computer and a reading device.

In addition, during lot processing, milling of the steel sheet material base material cannot be performed until a predetermined number of steel sheet material base materials have been collected, and during this time, the automatic tensile test system is forced to be in a suspended state, and the test Due to the delay in results, the number of finished products increases at the time of the results. This hinders the smooth operation of the automated tensile testing system.

For the above reasons, it is virtually impossible to automate a tensile test as long as a tensile test piece is created from a thin steel sheet material base material by loft processing.

Therefore, the present invention aims to provide a method for creating a tensile test piece that can be made one by one even from a thin steel plate material base material so that the tensile test can be automated.

Akane scolding ItanUit! Means for Determining In the method for preparing a tensile test piece according to the present invention,
A relatively thin piece of steel sheet material, which is somewhat larger than the dimensions and shape of the tensile test piece, is formed from the material by shearing, such as punching, and then the piece of material is shaped to have the dimensions and shape of the finished tensile test piece. It is sandwiched and clamped between a pair of guide plates having substantially the same dimensions and shape as the guide plate, while being pretensioned. At this time, since the size of the material piece is somewhat larger than the size and shape of the final tensile test piece, the peripheral portion of the material piece protrudes from between the pair of guide plates. These protruding portions are then removed by cutting, and after this cutting, the burrs are removed from the edges of the blank.

According to the present invention, by using a pair of guide plates in a double-connected manner, tensile test pieces can be prepared one by one from each piece of material obtained from a relatively thin steel sheet material base material. Therefore, the method for producing a tensile test piece according to the present invention can be easily automated.

Generally, when thin sheet steel material is stamped, the peripheral edges of the stamped product become hardened due to the stresses experienced during stamping. Therefore, in the present invention as well, when punching out a piece of material from a relatively thin base steel plate material, the peripheral edge of the piece of material is work hardened. Needless to say, such a phenomenon adversely affects the tensile test piece. In the present invention, such a hardened portion is cut off as a protruding portion, so it does not pose any problem.

In the present invention, when a piece of material is sandwiched between a pair of guide plates and clamped, pretension is applied to the piece of material, so that the protruding portion can be removed relatively easily and reliably during cutting. become. A preferable example of the cutting process at this time is end milling, and the pretension is within the elastic range.
It is preferably about 20% or less of the tensile strength.

In the present invention, when removing burrs from the edge of a piece of material after cutting, it is preferable to perform wire brushing while the piece of material is placed on a magnetic chuck stand.

EXAMPLE Next, an example of the method for preparing a tensile test piece according to the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, there is shown generally by the reference numeral 1 an automatic tensile test strip preparation line for carrying out the tensile test strip preparation method according to the present invention. In this automatic production line 1, each material piece W obtained from a relatively thin strip-shaped steel plate material 1 is processed one by one, and tensile test pieces are produced one by one. ing. Incidentally, such a piece of material W is made from a steel plate material by, for example, punching, and in this case, the size and shape of the piece of material W are made somewhat larger than the specimen P for tensile test.

The automatic production line 1 includes a fixed conveyance table 2 for conveying the material pieces, and along the fixed conveyance table 2, various processing stations for processing the material pieces W are sequentially arranged. In other words, with respect to the fixed transport platform 2, q
AAA material supply station 3
, a first cutting station 4, a second cutting station 5, and a burr removal station 6 are provided along the flow of the production line.

A so-called turner 7 is arranged in the blank feed station 3, and this turner 7 consists of a disc member with a cross-shaped groove 8, which is rotatably driven at the left end of the fixed conveyor table 2. There is. The turner 7 accommodates material pieces W obtained from a relatively thin strip-shaped steel sheet material base material in its cross-shaped groove 8, and also supplies these material pieces W one by one to the automated production line 1. Work to provide that direction.

That is, by rotating the turner 7 by 90 degrees, the material pieces W arranged radially within the cross-shaped groove 8 are
They are successively oriented to the supply position, ie, to a position aligned with respect to the fixed conveyor table 2. In FIG. 1, a piece of material so oriented is illustrated as I'll.

Such a piece of material W1 is conveyed by a transfer machine (part of which is designated by reference numeral T in FIG. 1) to the area of a first cutting station 4 and placed on a fixed conveyor 2. placed in second place. Note that the transfer device may be of any suitable type; for example, a type equipped with a vacuum puller is preferable.

The first cutting station 4 includes a pusher device 9.
, a clamping device 10 and a cutting device such as an NC milling machine 11 are arranged.

The pusher device 9 receives the material piece Wl sent from the material piece supply station 3 and sends it to the clamp device 10. It will be clear to those skilled in the art that such a pusher device 9 can be constructed as appropriate.

As shown in an enlarged view in FIG. 2, the clamp device 10 consists of a pair of guide plates 12, and these guide plates 12 have substantially the same dimensions and shape as the finishing tensile test piece P. One of the guide plates 12 has pins at both ends thereof, and openings for accommodating the pins of one guide plate 12 are provided at both ends of the other guide plate. Therefore, the pins of the pair of guide plates enter the openings, so that the two guide plates are perfectly aligned.

The material piece Wl sent out from the pusher device 9 is sandwiched and clamped between a pair of guide plates 12 while being given pretension. Pre-tensioning is performed by applying tension to the material piece 1I11 in advance and then placing the material piece 1!1 between the pair of guide plates 12.
This may be realized by sandwiching the material piece w1 between the pair of guide plates 12, or by placing a piece of material w1 between the pair of guide plates 12 and applying tension to the material piece w1 when cribbing.

As mentioned above, the dimensions and shape of the material piece are larger than the final tensile test piece P, so when the material piece W1 is clamped between the pair of guide plates 12, the peripheral part of the material piece W1 is attached to the guide plate. It will appear from 12 onwards. One side of this protruding portion is removed by cutting using an NC milling machine.

In this case, an end mill is preferably used as the cutting tool. As mentioned earlier, when the material piece 1111 is sandwiched between the pair of guide plates 12 and clamped, the material piece Wl is pretensioned and placed in a tensioned state, so that the protruding portion can be removed relatively easily and reliably during cutting.

The material piece W1, which has been machined on only one side in the first cutting station 4, is then sent to the second cutting station 5 by the above-mentioned transfer machine, where the material piece Wl The other side is machined. The second cutting station 5 is also provided with a pusher device 9'', a clamp device 10' and a cutting device 11'' similar to those in the first cutting station 4.

The second cutting station 5 will therefore not be described further.

The workpiece W1 completely cut in the second cutting station 5 is then sent to the burr removal station 6 by a transfer machine as described above. As shown in an enlarged view in FIG. 3, the burr removal station 6 includes a magnetic chuck stand 13 installed on the fixed conveyance table 2 and a rotating brush 14. In addition to thin metal wires, synthetic resin wires and the like can be used as the brush material.

The magnetic chuck table 13 is equipped with an electromagnetic means (not shown), and when the material piece v11 after cutting is placed on the magnetic chuck table 13, the electromagnetic means is excited and the material piece W1 is transferred to the magnetic chuck table. 13
fixed on top. A rotating brush 14 is applied to the material piece Ml fixed on the magnetic chuck table 13, and then the rotating brush 14 is moved along the material piece Ml, thereby removing burrs from one side of the material piece Wl. be done. After the removal of burrs from one side of the piece of material W1 is completed, the piece of material W1 is turned over, and the removal of burrs from the other side of the piece of material is performed in the same manner. When such burr removal is performed, 1llll of the material pieces will be obtained as a finished tensile test piece P.

Such a finished tensile specimen P is then sent to a measuring device 15 for measuring its thickness and width. Needless to say, this measuring device 15 is used to determine whether the increased tensile test piece P conforms to a predetermined standard, and is itself well-known.

Finished tensile test pieces P that do not meet the predetermined standards are removed from the fixed conveyance table 2 as rejected products. For such removal, a reject pusher device 16 and a reject storage box 17 are provided adjacent to the measuring device 14. It will be apparent to those skilled in the art that such reject pusher devices and reject bins may be constructed as appropriate.

The finished tensile test piece P determined to be an acceptable product by the measuring device 15 is then sent to an automated tensile test line, where a predetermined tensile test is performed and its data is processed.

Effects of the Invention As is clear from the explanation in Section L, according to the tensile test piece preparation method of the present invention, even if the steel sheet material base material is relatively thin, a tensile test can be performed from each steel sheet material base material. This results in an automatic tensile test piece production system that can produce one piece at a time.

Therefore, according to the present invention, the automatic tensile test system can be smoothly operated without having to suspend the automatic tensile test system unlike in the conventional case where tensile test specimens were created from a thin steel sheet material base material in lot processing. can be operated.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an automatic tensile test piece production line for carrying out the tensile test piece production method according to the present invention, and FIG. 2 is a clamp used in the automatic tensile test piece production line shown in FIG. FIG. 3 is an enlarged perspective view showing a pair of guide plates of the apparatus; FIG. 3 is an enlarged perspective view showing a magnetic chuck stand and rotating brush used in the automatic tensile test piece production line of FIG. 1; [Main reference numbers] 1 Tensile test piece automatic preparation line 2 Fixed conveyance table, 3 Material piece supply station 4 1st
Cutting station 5 Second cutting station 6 Harness removal station 9 Pusher device, 10 Clamp device 11 Cutting device (NC milling machine) 12 Guide plate, 13
Magnetic chuck stand 14 Rotating brush

Claims (2)

[Claims] (1) A method for preparing a tensile test piece of a relatively thin steel plate material, comprising: forming a material piece somewhat larger in size and shape than the final tensile test piece from the steel plate material base material; and a final tensile test piece. sandwiching and clamping the piece of material while applying pretension to the piece of material between a pair of guide plates having substantially the same dimensions and shape as those of the piece of material protruding from between the guide plates; A method for preparing a tensile test specimen, comprising: cutting a protruding portion; and removing burrs from the cut edge of the material piece. (2) The method for producing a tensile test piece according to claim 1, wherein the step of cutting the protruding portion of the material piece protruding from between the guide plates is performed by end milling.