JP2010194591A - Tool and apparatus for friction stir welding - Google Patents

Abstract

There are provided a pin for a friction stir welding tool and a friction stir welding apparatus using the same, in which a minute crack does not exist on the surface of the pin and the life can be extended.
A pin 1 is provided at the tip of a support 2 to be pressed against a member to be joined. The pin 1 is made of ceramics having a coating layer 3 on the surface.
[Selection] Figure 1

Description

  The present invention relates to a friction stir welding tool for joining members mainly composed of metal such as aluminum material, steel material, alloy materials thereof and MMC (Metal Matrix Composites), and the tool. The present invention relates to the friction stir welding apparatus used.

  In recent years, friction stir welding has been used as a method of joining using frictional heat generated from the members to be joined.

  This friction stir welding is performed, for example, in the order of steps (a) to (d) shown in FIG. First, in the step (a), the friction stir welding tool 50 is positioned so as to be perpendicular to the surface of the member 60 to be joined, and the friction stir welding tool 50 is rotated at a predetermined number of rotations. In the next step (b), the friction stir welding tool 50 is pressed against the surface of the member 60 to be joined with a predetermined pressure. Friction heat is generated between the member to be welded 60 and the friction stir welding tool 50, the member to be welded 60 is softened, and the pin 51 at the tip of the friction stir welding tool 50 is press-fitted into the member to be welded 60. Is done. In the next step (c), the pin 51 is embedded in the member to be joined 60, and the main body surface of the friction stir welding tool 50 contacts the member to be joined 60. During this time, the pressing of the pin 51 against the member to be joined 60 is maintained. At this time, a part of the member to be joined 60 around the pin 51 causes a composition flow phenomenon, and the laminated members 60 to be joined are joined. Then, in the step (d), the friction stir welding tool 50 is moved backward to separate the pin 51 from the member to be joined 60 and finish the joining.

  At present, the friction stir welding tool 50 used in these processes is becoming increasingly demanding for a long life, such as being difficult to break and being worn out. Patent Document 1 proposes a joining method by friction stirrer that meets such requirements.

International Publication WO2005 / 105360 Pamphlet

  However, when a minute crack generated during the production of the pin of the friction stir welding tool remains on the surface of the pin, it is difficult to further extend the life.

  An object of the present invention is to provide a friction stir welding tool and a friction stir welding apparatus that can further extend the life and have high reliability.

  A friction stir welding tool according to an aspect of the present invention is provided with a pin to be pressed against a member to be joined at the tip of a support, and the pin is made of ceramics having a coating layer on the surface.

  A friction stir welding apparatus according to an aspect of the present invention includes the friction stir welding tool and a control device that controls the operation of the friction stir welding tool.

  According to the friction stir welding tool according to one aspect of the present invention, since the minute cracks remaining on the surface when the silicon nitride sintered body is processed can be internalized, the mechanical characteristics are improved, The life of the friction stir welding tool can be extended, and a highly reliable tool can be provided.

  In addition, according to the friction stir welding apparatus according to one aspect of the present invention, the frequency of tool replacement can be reduced, and a friction stir welding apparatus with high long-term reliability can be provided.

It is a figure which shows typically an example of the tool for friction stir welding which concerns on one form of this invention, (a) is a perspective view, (b) is sectional drawing, (c) is the A section enlarged view. It is a figure which shows typically an example of the tool for friction stir welding which concerns on one form of this invention, (a) is a perspective view, (b) is sectional drawing, (c) is a B section enlarged view. (A), (b) is a perspective view which shows typically an example of the tool for friction stir welding which concerns on one form of this invention, respectively. It is a perspective view showing typically an example of the tool for friction stir welding concerning one form of the present invention. (A), (b) is a perspective view which shows typically an example of the tool for friction stir welding which concerns on one form of this invention, respectively. (A), (b) is a perspective view which shows a mode that each member was joined. It is a figure which shows the thermal radiation base produced using the tool for friction stir welding which concerns on one form of this invention, (a) is a top view, (b) is sectional drawing in the AA of (a), (c ) Is a bottom view. (A)-(d) is sectional drawing which each illustrates the process of friction stir welding typically.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings schematically shown. In addition, the same code | symbol is used when showing a common site | part in drawing.

  As shown in FIG. 1, a friction stir welding tool 100 includes a columnar support 2 that rotates about its axis, and a columnar pin 1 that presses the end of the support 2 against a member to be bonded. Have. Here, the pin 1 has a columnar shape smaller than the support 2, and the support 2 and the pin 1 are integrally formed.

  In the friction stir welding tool 100, the pin 1 is made of a silicon nitride sintered body, and has a coating layer 3 having a repair function on the surface of the pin 1. The silicon nitride-based sintered body refers to a silicon nitride composed of 50% by mass or more, and includes, for example, a sialon-based sintered body. The repair function means that even if a plurality of minute cracks having a width of 1 μm or less are generated in the silicon nitride sintered body, oxygen in the atmosphere reacts with silicon constituting the silicon nitride sintered body by heat treatment. This means that such cracks can be eliminated.

  As shown in FIG. 1C, the coating layer 3 covers the minute cracks 4 remaining on the surface when the silicon nitride sintered body is processed. The main component of the coating layer 3 is preferably, for example, any one of silicon dioxide, silicon carbide titanium nitride, titanium carbonitride, and a composite thereof, and the composition of these main components is a stoichiometric composition. Or any of non-stoichiometric composition may be sufficient. Here, the “main component” is a component that occupies 50% by mass or more with respect to 100% by mass of all components constituting the coating layer 3, and the following “main component” has the same meaning.

  The main component of the coating layer 3 may be amorphous hard carbon. In this case, the covering layer 3 may be formed in order from the surface of the pin 1 via titanium and silicon, and by adopting such a configuration, the adhesion of the covering layer 3 to the surface of the pin 1 can be increased. it can.

When the main component of the coating layer 3 is amorphous hard carbon, it is identified using Raman spectroscopy, and the vicinity of 1333 cm ⁻¹ , which is the peak position of diamond, and the vicinity of 1550 cm ⁻¹ , which is the peak position of graphite. It can be seen that each has a peak.

  Such amorphous hard carbon has a Vickers hardness of 20 GPa or more and 50 GPa or less and has a high hardness, so that it hardly wears even when used for friction stir welding.

  The amorphous hard carbon may have a peak biased to either diamond or graphite, but is preferably biased to the diamond peak position.

  When the main component of the coating layer 3 is amorphous hard carbon, the coating layer 3 may contain at least one metal selected from zirconium, tungsten and titanium and silicon.

  As described above, by containing at least one metal selected from zirconium, tungsten, and titanium and silicon, the residual stress inside the coating layer 3 can be reduced and the adhesion of the coating layer 3 can be increased.

Note that the amorphous hard carbon containing at least one metal of zirconium, tungsten, and titanium and silicon is different from the above-described amorphous hard carbon, and is 1480 cm ⁻¹ in identification by Raman spectroscopy. It has one peak in the vicinity.

  By having such a coating layer 3, minute cracks 4 remaining on the surface when the silicon nitride-based sintered body is processed can be internalized, so that mechanical characteristics are improved, and the friction stir welding tool 10 Can extend the lifespan.

  The friction stir welding tool 100 shown in FIG. 2 is similar to the friction stir welding tool 100 shown in FIG. 1 and includes a columnar support 2 that rotates about its axis, and a member to be joined at the tip of the support 2. It has a cylindrical pin 1 to be pressed.

  The pin 1 is provided on a support 2 made of a silicon nitride sintered body, and the covering layer 3 is formed on the surface of the support 2 around the pin 1, particularly on the surface of the support 2 facing the member to be joined. It is covered with a protective layer 5 having the same material as the main component. In this case, the coating layer 3 and the protective layer 5 may have any components other than the main components.

  As shown in FIG. 2C, the protective layer 5 covers the minute cracks 4 remaining on the surface when the silicon nitride sintered body is processed, like the coating layer 3.

  By having such a protective layer 5, since the minute cracks 4 remaining on the surface when the silicon nitride sintered body is processed can be internalized, the mechanical characteristics are improved, and the friction stir welding tool 100 is provided. Can extend the lifespan.

The pin 1 shown in FIGS. 1 and 2 is a cylindrical pin, but the surface around the pin 1 is
Grooves may be formed, and by forming such grooves, the stirring efficiency can be increased, and the members to be joined can be joined more firmly.

  The friction stir welding tool 100 shown in FIG. 3 has a plurality of triangular plane portions 6a on the surface of the pin 1 as shown in FIG. Further, as shown in (b), it has a plurality of quadrangular planar portions 6b, and each planar portion 5 has a side surface portion 7 that forms a substantially right angle and is continuous in a direction away from the shaft. In addition, the coating layer 3 may be formed on the surface including the flat portions 6b. Moreover, in (b), the side part 7 is formed so that it may continue only to one side of the square-shaped plane part 6b.

  The friction stir welding tool 100 shown in FIG. 4 is formed such that the side surface portion 7 is continuous over two sides of the rectangular flat surface portion 6.

  The silicon nitride sintered body forming the pin 1 and the support 2 preferably contains an oxide of a Group 3 element of the periodic table and silicon dioxide. In particular, the content of the oxide of the Group 3 element of the periodic table is preferably 1% by mass or more and 30% by mass or less, and is preferably 0.3 times or more and 15 times or less than the content of silicon dioxide.

  The oxide and silicon dioxide of the Group 3 element of the periodic table act as a sintering aid, and the oxide of the Group 3 element of the periodic table can increase the fracture toughness of the silicon nitride sintered body.

  By setting the content of Group 3 element oxide to 1% by mass or more, the silicon nitride sintered body can be densified at a lower temperature, and by setting it to 30% by mass or less Characteristics can be improved. Moreover, it becomes difficult to isolate | separate the part which a grain boundary phase contains many silicon dioxides by making content of the oxide of a periodic table group 3 element 0.3 times or more of content of silicon dioxide. For this reason, the omission of this part is suppressed and it becomes difficult to reveal the white pattern which impairs appearance. On the other hand, when the content of the Group 3 element oxide is 15 times or less of the content of silicon dioxide, the reaction between the Group 3 element oxide and silicon dioxide easily proceeds. For this reason, a liquid phase can be easily generated and mechanical properties can be further enhanced.

  In addition, as a group 3 element of a periodic table, yttrium (Y), erbium (Er), ytterbium (Yb), and lutetium (Lu) are preferable. In particular, erbium (Er) and ytterbium (Yb) are more preferable from the viewpoint of making the white pattern difficult to expose.

  Each content of Group 3 elements of the periodic table in the silicon nitride-based sintered body can be determined by ICP (Inductivity Coupled Plasma) emission analysis. The content of each oxide may be obtained by converting each of these elements into an oxide. Further, the content of silicon dioxide was obtained by obtaining the oxygen content in the silicon nitride sintered body by oxygen analysis, and subtracting the total content of oxygen constituting each of the oxides and aluminum oxide from this content. It is assumed that the entire content is used for constituting silicon dioxide, and is calculated by converting to silicon dioxide.

It should be noted that silicon nitride having a non-stoichiometric ratio represented by the composition formula SiO _2−x (where x is 0 <x <2) may be included in the silicon nitride sintered body.

  The silicon nitride sintered body forming the pin 1 and the support 2 preferably contains 0.002% by mass or more and 1% by mass or less of boron.

  Boron dissolves in the grain boundary phase and promotes amorphization of the grain boundary phase, so that volume shrinkage that occurs with the crystallization of the grain boundary phase is less likely to occur. Thereby, it becomes difficult to produce a clearance gap in a grain boundary phase, and a mechanical characteristic becomes still higher. The silicon nitride sintered body contains 0.002% by mass or more of boron, so that the improvement of the mechanical characteristics is clearly shown, and the sintering can be promoted by setting the boron to 1% by mass or less.

  The boron content in the silicon nitride sintered body can be determined by ICP emission analysis.

  The silicon nitride sintered body forming the pin 1 and the support 2 contains aluminum oxide and an oxide of a Group 3 element of the periodic table. The aluminum oxide content is preferably 0.1 to 2 times the oxide content of the Group 3 element of the periodic table.

  Aluminum oxide also acts as a sintering aid, like the oxides of Group 3 elements of the periodic table. By making the content of aluminum oxide 0.1 times or more the content of the oxide of the Group 3 element of the periodic table, the sinterability becomes higher. Thereby, the strength of the silicon nitride sintered body can be increased. Moreover, the fracture toughness of the silicon nitride sintered body can be increased by setting the content of aluminum oxide to 2.0 times or less of the content of the oxide of the Group 3 element of the periodic table.

  The aluminum content in the silicon nitride-based sintered body can be determined by ICP emission analysis. The content of aluminum oxide may be obtained by converting aluminum into an oxide.

  The silicon nitride sintered body forming the pin 1 and the support 2 preferably contains tungsten silicide in the grain boundary phase. In this case, it is preferable that the average crystal grain size of tungsten silicide is not less than 0.3 μm and not more than 3 μm. Originally, a small amount of Fe may be contained as impurities in silicon nitride powder, and Fe may be unevenly distributed after firing and become a source of destruction, which may reduce strength, but tungsten silicide has the property of dissolving Fe in solid solution. Therefore, uneven distribution of Fe after firing is suppressed. In addition to the effect of suppressing the uneven distribution of Fe, tungsten silicide has an effect of relaxing residual stress and promoting sintering.

  By making the average crystal grain size of tungsten silicide 0.3 μm or more, uneven distribution of Fe can be reduced. Further, by setting the average crystal grain size of tungsten silicide to 3 μm or less, tungsten silicide is easily dispersed in the grain boundary phase. For this reason, the effect of relieving the residual stress of the silicon nitride-based sintered body or promoting the sintering is enhanced.

Such tungsten silicide is represented by, for example, the composition of W ₃ Si, W ₅ Si ₃ , W ₃ Si _2, WSi _{2, and the} like, and can be identified using an X-ray diffraction method. In particular, it is preferable that the ratio of W ₅ Si ₃ / WSi ₂ is 0.1 or more. When this ratio is 0.1 or more, the heat resistance of the silicon nitride sintered body is increased.

  What is necessary is just to obtain | require the average crystal grain diameter of tungsten silicide based on JISR1670-2006. As the pretreatment, the surface or cross section may be polished with a paste containing diamond abrasive grains having an average particle diameter of 1 μm to obtain a mirror surface. Then, using a scanning electron microscope, the magnification is set so that there are 20 or more tungsten silicide crystal particles on the mirror surface, and then a reflected electron image is taken to determine the average crystal grain size of tungsten silicide.

_The ratio of W ₅ Si 3 / WSi _2, using the X-ray diffraction _method, W 5 of Si ₃ (411) plane and the (321) peak intensity _I in plane _(W 5 Si ₃₎ and the WSi ₂ ( The peak intensity I (WSi ₂ ) on the (101) plane and the (103) plane is obtained, and the ratio I (W ₅ Si ₃ ) / I (WSi ₂ ) may be obtained.

  As described above, the friction stir welding tool of the present embodiment has high mechanical properties and a long life, so that the composite member of the present embodiment in which a plurality of members to be joined are joined Increased reliability. In such a composite member, for example, plate-like metal members 8a and 8b are laminated and joined as shown in FIG. 6A, or plate-like metal as shown in FIG. 6B. There are members in which the members 8c and 8d are joined in a plane.

  As the composite member, for example, an insulating support substrate, a circuit member positioned on the upper side of the support substrate, and a cooling member via a heat dissipation member on the lower side of the support substrate, the heat dissipation member and the cooling member, It is also possible to adopt a configuration in which the components are joined by a friction stir welding tool.

  The composite member 200 shown in FIG. 7 includes an insulating support substrate 9, a first metal layer 10 a mainly containing at least one of titanium, zirconium, hafnium, vanadium, and niobium on the upper side of the support substrate 9 and copper. Circuit member 12 positioned sequentially through second metal layer 11a mainly composed of slag, and cooling member positioned below support substrate 9 via first metal layer 10b, second metal layer 11b and heat radiating member 13 14, and the heat dissipating member 13 and the cooling member 14 are joined by the friction stir welding tool 100. Since this composite member 200 uses a friction stir welding tool having a long life, the composite member 200 can be a composite member with high reliability of the joint.

  The friction stir welding apparatus (not shown) may include the friction stir welding tool of the present embodiment and a control device (not shown) that controls the operation of the friction stir welding tool. According to this, since the tool for friction stir welding with a long life is used, the replacement frequency of the tool can be reduced.

  Below, an example of the manufacturing method of the tool for friction stir welding of this embodiment is demonstrated.

  First, a cylindrical body made of a silicon nitride-based sintered body is prepared. The pin 2 is produced by grinding the outer peripheral surface on the tip side of the cylindrical body. Thereby, the tool for friction stir welding whose remainder other than the pin 2 is the support body 1 can be obtained.

  Next, the surface of the silicon nitride-based sintered body is coated with silicon dioxide as a main component by heat-treating the friction stir welding tool in an air atmosphere of 600 ° C. to 1500 ° C., for example, for 1 hour to 2 hours. The layer 3 may be formed.

  Further, the protective layer 4 made of the same material as that of the coating layer 3 can be coated on the surface of the support 2 facing the member to be joined by the heat treatment.

  In order to form amorphous hard carbon on the surface of the pin 1 and the support 2, either a CVD (Chemical Vapor Deposition) method or a PVD (Physical Vapor Deposition) method such as a sputtering method or an ion plating method is formed. Means may be used.

  For example, in order to form the coating layer 4 and the protective layer 5 at a low temperature by the plasma CVD method, first, a source gas and a carrier gas for forming the coating layer 4 and the protective layer 5 are supplied into the chamber chamber of the plasma CVD apparatus. By applying a voltage between the cathode (anode) where the friction stir welding tool is placed and the anode (anode), the electrons extracted from the cathode (anode) collide with the source gas and the carrier gas to generate plasma. The source gas component in the plasma may be deposited on each surface of the pin 1 and the support 2.

  Then, it can be formed by replacing the source gas and the carrier gas supplied to the chamber chamber by depositing amorphous hard carbon through titanium and silicon in order from the surface side of the pin 1 and the support 2. .

  In addition, what is shown in Table 1 should just be used as source gas and carrier gas which are supplied to a chamber chamber in order to deposit each material.

次に、本実施形態の摩擦攪拌接合用工具を構成する窒化珪素質焼結体の製造方法の一例について説明する。

Next, an example of a method for producing a silicon nitride sintered body constituting the friction stir welding tool of the present embodiment will be described.

  A predetermined amount of Group 3 element oxide powder and silicon dioxide powder as a sintering aid are added to the silicon nitride powder, and any of 2-propanol, methanol and water as a solvent, for example, a rotary mill , Wet mix in vibration mill, bead mill and barrel mill. In this case, depending on circumstances, dry mixing without using a solvent may be used.

  Here, the content of the oxide of the Group 3 element in the periodic table in the silicon nitride-based sintered body is 1% by mass or more and 30% by mass or less, and is 0.3 to 15 times the content of silicon dioxide. In order to make it, the content of the Group 3 element oxide powder of the periodic table with respect to the silicon nitride powder is 1% by mass or more and 30% by mass or less, the content of the silicon dioxide powder and The oxygen inevitably present in the silicon nitride powder may be not less than 0.3 times and not more than 15 times the total content calculated by assuming that all silicon nitride-based sintered bodies are silicon dioxide.

  The content of oxygen inevitably present in the silicon nitride powder may be determined according to JIS R 1603-2007.

  Further, it is also preferable to add boron in addition to the above sintering aid, and in order to make the boron content in the silicon nitride-based sintered body 0.002 mass% or more and 1 mass% or less, the silicon nitride powder In contrast, boron may be added in an amount of 0.002% by mass to 1% by mass.

  In order for the content of aluminum oxide in the silicon nitride-based sintered body to be not less than 0.1 times and not more than twice the oxide content of the Group 3 element of the periodic table, the silicon nitride powder is oxidized. The aluminum content may be 0.1 to 2 times the content of the Group 3 group element oxide.

  In addition, if the silicon nitride sintered body contains tungsten silicide in the grain boundary phase and the average crystal grain size of tungsten silicide is 0.3 μm or more and 3 μm or less, the average grain size is 0.3 μm or less and 3 μm or less. At least one of a material, a carbide, an oxide, and a nitride may be added in an amount of 0.1% by mass to 10% by mass with respect to the silicon nitride powder. Tungsten silicide is present in the grain boundary phase as tungsten silicide having an average crystal grain size of 0.3 μm or more and 3 μm or less as it is after heat treatment described later. Further, tungsten carbide, oxide and nitride react with silicon nitride during the heat treatment, and exist in the grain boundary phase as tungsten silicide having an average crystal grain size of 0.3 μm or more and 3 μm or less.

  The mixed powder is formed into an arbitrary shape by a desired forming means, for example, any one of livelihood means such as dry pressure forming, cold isostatic press forming, extrusion forming, injection forming, and casting forming.

  Depending on the molding means, preparation such as granulation by spray drying or the like, or preparation of a highly viscous clay, etc. may be required, but a normal ceramics molding procedure may be followed.

  When drying and degreasing are necessary after molding, heat treatment may be performed at 50 ° C. or higher and 1400 ° C. or lower in any of nitrogen, air, and vacuum.

  About baking, what is necessary is just to heat-process on 1600 degreeC or more and 2000 degrees C or less conditions in nitrogen atmosphere.

  In the case of baking at 1800 ° C. or higher, silicon nitride may be decomposed, and thus baking may be performed under a nitrogen partial pressure of 1 atm or higher.

  In particular, heat treatment is preferably performed at 1650 ° C. or higher and 1850 ° C. or lower in order to suppress abnormal grain growth of silicon nitride crystal grains.

  Furthermore, a denser sintered body can be obtained by performing heat treatment using means such as hot isostatic pressing (HIP) after the heat treatment as described above. When using this hot isostatic pressing (HIP), the temperature is preferably 1500 ° C. or higher and 1750 ° C. or lower.

  As described above, the friction stir welding tool of the present embodiment includes a pin at the tip, and this pin is made of a silicon nitride sintered body having excellent mechanical properties, and the surface of the pin has a repair function. Because it has a layer, it can internalize minute cracks that remain on the surface when the silicon nitride sintered body is processed, so the mechanical properties are improved and the life of the friction stir welding tool is extended. be able to.

  First, as shown in FIG. 6 (b), plate-like metal members 8c and 8d were put in contact with each other in a planar manner, and a composite member was produced using a friction stir welding tool.

  Each material of the plate-like metal members 8c and 8d was an Al—Mg—Si alloy. Moreover, each thickness of the metal members 8c and 8d is 4 mm, and the length of a junction part is 200 mm.

  The main components of the coating layer 3 and the protective layer 5 in FIG. 2 are as shown in Table 2, and those with a horizontal line in the column of the coating layer and / or protective layer have no coating layer and / or protective layer Indicates.

  The contents of materials (group 3 element oxide, silicon dioxide, aluminum oxide and boron) included in the silicon nitride sintered body forming the pins and the support are as shown in Table 2. Yes, those with a horizontal line in each component column indicate that the corresponding component is not included.

  Each content of the oxide and aluminum oxide of the Group 3 element in the periodic table in the silicon nitride sintered body is determined by ICP emission analysis. The content of each oxide was determined by converting each of these elements into an oxide.

  Further, the content of silicon dioxide was obtained by obtaining the oxygen content in the silicon nitride sintered body by oxygen analysis, and subtracting the total content of oxygen constituting each of the oxides and aluminum oxide from this content. The content was considered to be used to constitute silicon dioxide, and was calculated by converting to silicon dioxide.

  The boron content in the silicon nitride sintered body was determined by ICP emission analysis.

  In addition, the average crystal grain size of tungsten silicide contained in the grain boundary phase is as shown in Table 2, and those with a horizontal line in the column of tungsten silicide do not contain tungsten silicide in the grain boundary phase. It shows that.

  The average crystal grain size of this tungsten silicide was determined according to JIS R 1670-2006. As a pretreatment, the cross section of the silicon nitride-based sintered body was polished with a paste containing diamond abrasive grains having an average particle diameter of 1 μm to obtain a mirror surface. Then, using a scanning electron microscope, the magnification was set to 4000 times, and then a reflected electron image was taken to obtain an average crystal grain size of 20 tungsten silicide crystal particles.

  Using the friction stir welding tool shown in Table 2, the plate-like metal members 6c and 6d were joined with a pin insertion depth of 4 mm, a pin rotation speed of 1600 rpm, and a pin movement speed of 0.6 m / min. did.

  A plurality of composite members were produced by the above-described method, and the accumulated length (total length) of the joined portion until an unjoined portion was generated was measured to evaluate the life of the friction stir welding tool.

  The longer the total length of the joint, the longer the life of the friction stir welding tool, and the shorter the total length of the joint, the shorter the life of the friction stir welding tool.

  The occurrence of unbonded portions was confirmed by the X-ray transmission method.

試料Ｎｏ．１，６１，６３，６５は、ピンが窒化珪素質焼結体からなり、ピンの表面に修復機能を備えた被覆層を有していることから、被覆層のない試料Ｎｏ．６７より寿命が長い。

Sample No. In Nos. 1, 61, 63 and 65, since the pin is made of a silicon nitride sintered body and has a coating layer having a repair function on the surface of the pin, Longer than 67.

  Sample No. Nos. 2 to 60 are covered with a protective layer made of the same material as that of the covering layer, so Longer than 1 Sample No. 61 and 62, sample no. 63 and 64, sample no. Even when comparing 65 and 66, it was found that the life was long when the protective layer of the same material as the coating layer was coated.

  In Sample Nos. 4, 6 to 26, 28, 34, 36 to 56, and 58, the silicon nitride sintered body contains an oxide of a Group 3 element of the periodic table and silicon dioxide. Further, the content of the oxide of the Group 3 element of the periodic table is 1% by mass or more and 30% by mass or less and is 0.3 to 15 times the content of silicon dioxide. Sample No. Life is longer than 3, 5, 27, 29.

  Sample No. In Nos. 9 to 24 and 39 to 54, the silicon nitride sintered body contains aluminum oxide and an oxide of a Group 3 element of the periodic table. Furthermore, the content of aluminum oxide is 0.1 to 2 times the content of the oxide of the Group 3 element of the periodic table. 4. Life is longer than 4, 6-8, 25, 26, 28.

  Sample No. Nos. 12 to 22 and 42 to 52 contain 0.002% by mass to 1% by mass of boron. Longer life than 11,23,41,53.

  Sample No. 16-19 and 46-49, the silicon nitride sintered body contains tungsten silicide in the grain boundary phase, and the average crystal grain size of tungsten silicide is 0.3 μm or more and 3 μm or less. Sample No. Life is longer than 15, 20, 45, 50.

DESCRIPTION OF SYMBOLS 1: Pin 2: Support body 3: Cover layer 4: Crack 5: Protective layer 6: Plane part 7: Side part 8: Metal member 9: Support substrate 10: 1st metal layer 11: 2nd metal layer 12: Circuit member 13: Heat dissipation member 14: Cooling member 100: Friction stir welding tool 200: Composite member

Claims (10)

A friction stir welding tool provided with a pin to be pressed against a member to be joined at the tip of a support, wherein the pin is made of a ceramic having a coating layer on a surface thereof. 2. The friction stir welding tool according to claim 1, wherein a surface of the support around the pin is covered with a protective layer having the same material as the main component constituting the coating layer. 3. The friction stir welding tool according to claim 1, wherein the ceramic constituting the pin is a silicon nitride-based sintered body containing silicon nitride as a main component. The friction stir welding tool according to claim 3, wherein the silicon nitride sintered body contains an oxide of a Group 3 element of the periodic table and silicon oxide. The oxide content of the Group 3 element of the periodic table is 1% by mass or more and 30% by mass or less, and is 0.3 to 15 times the content of silicon dioxide. 4. The friction stir welding tool according to 4. 6. The friction stir welding tool according to claim 3, wherein the silicon nitride sintered body contains 0.002% by mass or more and 1% by mass or less of boron. The silicon nitride-based sintered body further contains aluminum oxide in an amount of 0.1 to 2 times the content of an oxide of the Group 3 element in the periodic table. The friction stir welding tool according to any one of the above. The friction stir welding tool according to any one of claims 3 to 7, wherein the silicon nitride sintered body contains tungsten silicide in a grain boundary phase. 9. The friction stir welding tool according to claim 8, wherein an average crystal grain size of the tungsten silicide is 0.3 μm or more and 3 μm or less. A friction stir welding apparatus comprising: the friction stir welding tool according to any one of claims 1 to 9; and a control device that controls the operation of the friction stir welding tool.

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