JPS61172692A - Production of different metallic joint materials - Google Patents

Abstract

PURPOSE:To permit easy joining of a combination of different materials by joining preliminarily two members consisting of different materials to an explosive cladding method then joining a member to be bound to the joint body thereof by friction welding. CONSTITUTION:The different metallic joint body 3 constituted of the members to be bound by the explosive cladding method is prepd. beforehand. More specifically, a round plate or square plate, etc. are cut out of a broad plate-shaped explosively clad material and are subjected to perforating, etc. The bonding members 1, 2 consisting of the same metal are then successively joined to both ends of the body 3 by the friction welding method to form friction welded surfaces 4, 5. The flash of the frictional welding and the excess length part of the different metallic joint body are finally removed to finish the joint body to a prescribed size. The joining of the different metals which are heretofore difficult to be directly joined is thus made easy by such method.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing rod-shaped or tubular dissimilar metal joint materials, more specifically, by an explosive crimping method and a friction welding method.
0 Concerning a manufacturing method for joint materials that can easily achieve strong joining of dissimilar metals that are originally difficult to join or cannot be joined by friction welding method Conventional technology Due to the development of new industrial technology, performance may vary. The demand for rod-shaped or tubular materials made of two or more types of materials is increasing year by year. When joining rod-shaped or tubular objects, the friction welding method uses the frictional heat of the two members to connect them together, and is used in many mechanical and electrical industries. ing. This friction welding method can easily perform high-precision welding, has short welding time and high work efficiency, does not require a welding rod or solvent, and does not require special bevel processing. Due to the advantages of saving materials and reducing man-hours, the field of application tends to expand more and more. However, the combinations of materials that can be joined by friction welding are still limited, especially combinations of metals that easily oxidize at high temperatures, such as titanium, niobium, tantalum, zirconium, and hafnium, and ferrous materials such as steel and stainless steel. Currently, it is not possible to obtain a bond with satisfactory toughness and strength for combinations of materials with low eutectic temperatures, such as combinations of aluminum and copper or carbon steel. Regarding manufacturing technology, JP-A-51-11047, JP-A-59-
There are publications such as No. 61584.

JP-A No. 51-11047 describes the combination of similar metal materials such as titanium, tantalum, zirconium, and hafnium, which are easily oxidized at high temperatures, and the friction welding of dissimilar materials in which these metals are combined with each other, or There is a friction welding method between metals such as carbon steel or other non-ferrous metals other than those mentioned above, but in this method, after reaching a predetermined temperature by friction pressurization, a predetermined pressure is applied to reach a predetermined pressure. The disadvantage is that the selected friction welding conditions are narrow and strict, such as stopping the rotation immediately after the welding process, and that productivity is significantly impaired.

In addition, JP-A No. 59-61584 describes α + β angle 2 times, especially the upset pressure (P2) and friction pressure (P8) during friction welding, the diameter (d) of the welded materials, and the rotation speed difference (n ), Phiro≧660 (ndPl)−
Although this method is effective for friction welding between α+β type titanium alloys, it does not mention joining dissimilar metals, for example, joining titanium and steel. do not have.

There have been many research reports on joints made from a combination of aluminum and copper, but the melting point of aluminum is 86.
0°C, that of copper is 1083°C, and it is known that when the two are brought together and heated to 548°C, a melt having a eutectic point composition is produced from the interface.

This solidified layer of eutectic composition and the 0 phase (
Since CuA4 intermetallic compound) is hard and brittle, its presence at the joint surface deteriorates the performance of the joint.

In the case of a combination of aluminum and carbon steel, when the temperature reaches SOO°C or higher, an alloy layer is formed on the joint surface, and the performance of the joint similarly deteriorates. All of these problems arise because dissimilar metals are attempted to be joined by direct friction welding.

On the other hand, there is an explosive crimping method for joining metal materials, and it is possible to instantly join almost all metal materials in a cold state. In particular, it is difficult to obtain satisfactory joint performance using friction welding when using metals that easily oxidize at high temperatures, such as titanium, niobium, tantalum, zirconium, and ferrous materials such as steel and stainless steel. It is possible to easily and firmly join combinations of materials having low eutectic temperatures, such as combinations of aluminum and copper or carbon steel. These joined bodies fully satisfy mechanical properties such as toughness and strength, and are widely used in the chemical industry, mechanical industry, etc. However, metal materials that can be joined using the explosive crimping method are subject to limitations in the manufacturing process, so the thickness of the joined body formed by - times of explosive crimping is as large as the thickness that can be joined using the friction welding method. I can't. That is,
For example, when joining pure titanium to carbon steel, the thickness of pure titanium is approximately 20μ1, while the thickness of pure aluminum is approximately 40μ
This is the maximum plate thickness that can be explosively crimped, but if a thickness greater than that is required, a method of joining pure titanium or pure aluminum in two or more explosive crimping processes may be considered. However, although it is possible to form a bonded body with a desired plate thickness by repeating explosive crimping a plurality of times, there is a drawback that the more explosive crimping is repeated, the lower the yield of the explosive crimping material becomes. In addition, in the explosive crimping method, dissimilar metal joint materials are actually cut out from a wide plate-shaped clad plate, which requires a lot of cutting man-hours.

The longer the dissimilar metal joint material to be obtained and the thicker the clad plate, the more man-hours required. moreover,
When the dissimilar metal joint material is in the shape of a round bar or a tube, there is a drawback that it is necessary to cut the cut out square bar-shaped dissimilar metal joint material using a lathe or the like.

Problems to be Solved by the Invention The method of the present invention utilizes the characteristics of friction welding to dramatically improve the bonding performance at the interface of dissimilar metal joint materials, which is difficult to join with sufficient performance using friction welding. By combining different types of scrap metal materials joined using the explosive crimping method, and resulting in friction welding between the same electrical metals, we are able to manufacture rod-shaped or tubular joints of high quality and with excellent productivity. This is what makes it possible.

Means for Solving the Problems The present invention will be explained in detail with reference to the drawings. Both FIG. 1 and the fsz diagram are partial views of a joint material obtained by the method of the present invention. In Fig. 1, the coupling members 1 and 2 are tubular or rod-shaped joint materials friction welded to both ends of a dissimilar metal joined body 30 obtained by explosive crimping, and Fig. 2 shows dissimilar metals obtained by explosive crimping. A joining member 2 is frictionally welded to one end of a joined body 3. 4 and 5 are friction welding surfaces, and %6 is a welding boundary formed by explosive crimping of dissimilar metal materials. Connecting member! and 2 may be dissimilar metals to which the explosive crimping method can be applied, but it is preferable that the member on the friction welding side of the dissimilar metal joined body 3 and the joining member 1.2 are of the same kind of metal. It is not necessarily limited to the same type of material as long as it can be friction welded. In particular, the present invention is particularly effective when the coupling member 1.2 is made of a metal that easily oxidizes due to high temperature when friction welded together, or a metal that tends to melt the friction surface and form a brittle alloy layer. .

Examples of the former include titanium, niobium, tantalum, hafnium, etc. and other metal materials, and examples of the latter include a combination of aluminum and copper or carbon steel.

The manufacturing method will be explained below.

A dissimilar metal bonded body (3) composed of these members to be bonded is prepared by the explosive crimping method. This joint is formed by cutting out a wide plate-shaped explosive crimp clad material, and its shape is a round plate or a square plate. Further, when the members to be joined are tubular, drilling a hole in the joined body in advance, preferably having the same size as the inner diameter of the pipe, facilitates drilling after joining.

Next, members to be joined made of the same kind of metal are sequentially joined to both ends of this joined body by friction welding (4) and (5). In order to reduce the effect of frictional heat on the internal and external parts of the dissimilar metal joined body and to suppress the formation of a brittle alloy layer at the dissimilar metal interface, the welding order using the friction welding method is preferably starting from members with a low melting point. Or, start from the side of the thicker plate that makes up the explosive crimped joint. If a dissimilar metal bonded body formed by the explosive welding method can be manufactured with one end having the desired thickness, it can be made by just joining the other end by the friction welding method as shown in Figure 2. It is possible to form a joint similar to that shown in FIG.

At the end, or each time each friction welding process is completed, we can simultaneously remove the debris from the joint caused by friction welding and the excess length of the dissimilar metal joined body previously formed by explosive crimping, thereby reducing the number of cutting steps. By finishing it to a predetermined size without addition, an integrated rod-shaped or tubular dissimilar metal joint material is formed.

Example This will be explained in more detail with reference to Examples below.

Example 1 First, a TP35C titanium round bar with a diameter of 25 mm and a length of 100 mm and an 8450 mechanical structural carbon steel round bar with the same dimensions were prepared, respectively. 5■'rpssc titanium plate and plate thickness 15 WO
Made from clad wood made of 845C.

A joined body having a diameter of 27 disks was prepared by turning.

Next, under the conditions shown in Table 1, the titanium round bar was friction welded to the titanium surface of this joined body, and then the 84SC of this joined body was
The 845C round bar was friction welded to the steel surface to form a single joint material. On the other hand, two joint materials were manufactured by friction welding a titanium round bar and a 545C round bar under the same friction welding conditions. Similarly, before friction welding was performed, oxide films and the like were removed from the friction weld surfaces of each material by grinding.

For the obtained joint materials, in order to evaluate the mechanical properties of the joints, round bar tensile test pieces with a diameter of 27 cm were made.
The tensile strength was measured and was as shown in Table 1.

As a result of evaluating mechanical properties, 1 the titanium-steel rod joint material produced by the method of the present invention broke at the titanium bar. Since its tensile strength was 43.5 kff/-,
It is expected that the joint strength of the explosive crimp and friction weld surfaces will be even stronger. Also.

Two titanium pieces manufactured under the same friction welding conditions.
The joint material of the steel bar broke from the friction welding surface of dissimilar metals, and the joint strength was 20.5 ktf/- or less. The tensile strength of the TP35C material used for production is 42. .

kff/d, that of 545C material is 51. Oktf/
- The tensile strength of the joint was significantly inferior to the strength of the material.

From this, the mechanical properties of the dissimilar metal joint material manufactured by the method of the present invention are superior to those of the joint manufactured by the conventional friction welding method.

Margin Example 2 First, Al100 with a diameter of 16 m and a length of 200 mm
We prepared a full miniram round bar and a 545C carbon steel round bar for machine structures with the same dimensions, and also prepared Al100 aluminum plates with a thickness of 15 and a 545C steel plate with a thickness of 15mm, which had been previously formed using the explosive crimping method. Consisting of two pieces of wood,
A disc-shaped zygote with a diameter of 18 cm was prepared by rotation.

Next, under the conditions shown in Table 2, the aluminum round bar was friction welded to the aluminum surface of this joined body, and then the 545C round bar was friction welded to the 845C steel surface of this joined body.
It was used as a joint material for books. On the other hand, under the husband's same friction welding conditions, an aluminum round bar and an 845C round bar were friction welded to produce two joint materials.

In order to evaluate the mechanical properties of the joints, the obtained joint materials were subjected to a tensile test on a round bar with a test piece diameter of 15.6 cm and a bending test with a bending diameter of 9 cm according to the method. It was as shown in Table 2.

From the tensile test results, the aluminum-steel bar joint material produced by the method of the present invention broke at the aluminum bar. Since its tensile strength was 8.4 kff/-, it is expected that the joint strength between the explosive pressure bonding surface and the friction pressure bonding surface will be even stronger. Further, the joint materials of two aluminum-steel bars manufactured under the same friction welding conditions were both broken at the dissimilar metal friction welding surfaces, and the joint strength was less than a, 5 krf/-. A used for production
The tensile strength of IIGO material is 8.2 kff/-, 845
Since that of C is 51.0 kff/-, compared to the material strength.

The tensile strength of the joint was extremely poor.

In addition, from the bending test results, it was found that the aluminum-steel rod joint material manufactured by the method of the present invention was bent at a bending radius of so't without cracking, whereas the two joint materials manufactured under the same friction welding conditions were In all of the aluminum-steel rod joint materials, opening cracks occurred from the friction welding surfaces of dissimilar metals at bending angles of 25" or less.

Therefore, the mechanical properties of the dissimilar metal joint material manufactured by the method of the present invention are superior to those of the joint manufactured by the conventional friction welding method.

Below is a margin Effect of the present invention The present invention combines dissimilar metal joined bodies previously joined by explosive crimping method with friction welding method. To facilitate joining of a combination of dissimilar metal materials that can only be joined under certain conditions.

In addition, by joining similar metal materials to one or both ends of a dissimilar metal joint formed by explosive crimping using friction welding, it is possible to determine the amount of offset force, friction pressure, friction time per rotation, and bonding caused by the combination of joining materials. Restrictions on manufacturing conditions such as the atmosphere can be relaxed or even eliminated.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are partial views of a dissimilar metal joint material according to the present invention. 1.2... Rod-shaped or tubular joining member, 3... Dissimilar metal joined body by explosive crimping method, 4.5... Friction welding surface, 6... Joining boundary by explosive crimping method. Patent applicant Asahi Kasei Kogyo Co., Ltd. Figure 2 Procedural amendment (voluntary) April 5, 1985 Director General of the Patent Office Manabu Shiga 16 Display of case 1985 Patent application No. 10768 2 Name of invention Dissimilar metal joint Material manufacturing method 3, relationship with the case of the person making the amendment Patent applicant 1-2-6-4 Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture, "Detailed description of the invention" column 5 of the specification subject to amendment, amendment Contents (The Detailed Description of the Invention column in Specification 11 is amended as follows. (2) Table 2 on page 16 of the Specification is amended as shown in the attached sheet.

Claims (3)

[Claims] (1) Two members made of different materials are first formed into a single joined body by explosive crimping, and then the members to be joined are friction welded to one or both ends of the joined body. Manufacturing method of metal joint material (2) The method according to claim 1, wherein one of the two members is a metal material that is easily oxidized at high temperatures. (3) The method according to claim 1, wherein the two members are made of a metal material whose friction surfaces are likely to melt and form a brittle alloy layer when friction welding is performed.