Compound and method for manufacturing the same

Abstract

To provide a conjugate having a new structure formed by bonding a TiNi-based shape memory alloy material and a metallic material different therefrom without welding a bonding interface; and to provide a manufacturing method thereof.SOLUTION: A conjugate 1 includes a fixed member 10 comprising a TiNi-based shape memory alloy material, and a solid proximal member 20 comprising a metallic material different from the fixed member 10. The fixed member 10 has a tubular part 12. The proximal member 20 has a primary part 22, and a part 24 to be inserted extending from the primary part 22. The tubular part 12 is tightened and fixed by utilizing super elasticity of the fixed member 10 to the part 24 to be inserted.SELECTED DRAWING: Figure 1

Description

【Technical Field】 【0001】 The present invention relates to a composite body formed by bonding a TiNi-based shape memory alloy material and a metal material different therefrom, which can be used, for example, for a catheter guide wire, and a method for manufacturing the same. 【Background Art】 【0002】 The TiNi-based shape memory alloy exhibits superelasticity in which deformation due to an external force returns to its original shape simultaneously with its release, and a shape memory effect in which it returns upon heating. In this case, the former occurs when used in the austenite phase (high-temperature phase) at a temperature higher than the shape recovery temperature, and the latter occurs in the case of the low-temperature martensite phase (low-temperature phase). 【0003】 For example, in the medical field, a TiNi-based shape memory alloy that exhibits superelasticity based on the above-described effect is used as a main member of a catheter device for intravascular treatment. A catheter is a flexible tube made of silicone, polyurethane, fluororesin, etc., which is inserted into the digestive tract, ureter, blood vessel, etc., and is used for discharging body fluids and injecting drug solutions and contrast agents. 【0004】 Intravascular treatment involves diagnosing and treating diseases via a catheter introduced into a blood vessel, such as dilating a stenosed blood vessel caused by arteriosclerosis or stopping the blood flow to an aneurysm. At that time, the guide wire is sent to the disease site first as a leader of the catheter. 【0005】 In the case of heart disease, the guide wire is inserted into the target site while selecting many branched blood vessels in a blood vessel reaching 1.8 m. Its function needs to have flexibility that can freely pass through the bent blood vessels at the tip, flexibility that does not damage the blood vessels, and high-rigidity spring characteristics that transmit the hand operation at the base to the tip. 【0006】 Superelastic guidewires made of TiNi-based shape memory alloys, while having some shortcomings in the rigidity of their base, offer unparalleled resilience and flexibility at the tip, making them widely used today for the diagnosis and treatment of diseased areas. 【0007】 As a device exhibiting such characteristics, Patent Document 1 discloses a guide wire with a superelastic metal wire as the core material, in which the cross-sectional area of ​​the inner core on the main body side is made relatively large and the cross-sectional area of ​​the inner core on the tip side is made relatively small, thereby making the main body part having the inner core on the main body side relatively rigid and the tip part having the inner core on the tip side relatively flexible. 【0008】 Furthermore, Patent Document 2 discloses a reusable catheter guidewire in which strain characteristics are improved by coating a core wire made of a TiNi-based shape memory alloy that exhibits thermoelastic martensitic transformation with an outer periphery member. 【0009】 On the other hand, in order to improve the flexibility of the tip and the rigidity of the base, a construction technology has been disclosed in which the tip is made of a TiNi-based shape memory alloy and the base is made of a spring material such as stainless steel, that is, a technology for welding and pressure bonding the butt joints of dissimilar metals. 【0010】 As examples of such technologies, Patent Document 3 describes a technique for joining a TiNi-based shape memory alloy with a different metal by heating and pressurizing, and Patent Document 4 describes a technique for joining guide wire cores made from titanium-free alloys using one or more of the following methods: welding, brazing, or adhesive joints. Specifically, Patent Document 3 describes a technique for joining a TiNi-based shape memory alloy member with a different metal member, in which the joining surfaces of both members are brought into contact with each other, the joining area is locally reacted and melted, the parts of both members in contact with the molten area are softened at high temperature, and at the same time the joining area is compressed at high pressure to form a hot forged structure at the joining interface. [Prior art documents] [Patent Documents] 【0011】 [Patent Document 1] Japanese Patent Application Publication No. 60-007862 [Patent Document 2] Japanese Patent Application Laid-Open No. 61-106173 [Patent Document 3] Japanese Patent Application Publication No. 05-185251 [Patent Document 4] Special publication 2015-511833 [Overview of the project] [Problems that the invention aims to solve] 【0012】 A common method for joining dissimilar metals involves applying an electric current to an electrode, bringing it into contact with the objects to be joined, and then separating them to melt the contact interface with an arc discharge, thereby pressing the two materials together. However, in TiNi-based shape memory alloys, the Ti in the alloy has a strong affinity for oxygen, and an oxide film is formed simultaneously with interfacial melting. As a result, the bonding boundary is hindered by the oxide, making it difficult to obtain the required bonding strength. 【0013】 Therefore, the present invention aims to provide a new type of composite body formed by bonding a TiNi-based shape memory alloy material and a different metal material without welding the bonding interface, and a method for manufacturing the same. [Means for solving the problem] 【0014】 The present invention provides a method for manufacturing the first composite, A fixed member made of a TiNi-based shape memory alloy material, having a tubular portion, is cooled to a martensite phase state. A portion of a solid base member made of a metal material different from the TiNi-based shape memory alloy material is inserted into the tubular portion. By returning the fixed member to the austenite phase at room temperature, the superelasticity of the fixed member is used to tighten and fix the tubular portion to the insertion portion. A method for manufacturing a composite is provided. 【0015】 As a method for manufacturing a second conjugate, the present invention provides a method for manufacturing a first conjugate, wherein in the state before the insertion, the largest one of the outer circumferences of the inserted portion is larger than the inner circumference of the tubular portion, and during the insertion, the inserted portion expands at least temporarily the inner cavity of the tubular portion to provide a method for manufacturing a conjugate. 【0016】 As a method for manufacturing a third conjugate, the present invention provides a method for manufacturing a first or second conjugate, wherein after the clamping and fixing, a portion of the tubular portion of the fixed member is drawn using a wire drawing die to provide a method for manufacturing a conjugate. 【0017】 As a method for manufacturing a fourth conjugate, the present invention provides a method for manufacturing any one of the first to third conjugates, wherein the inserted portion has a tapered shape that tapers towards the tip, the cooling of the fixed member is performed in a state where a part of the inserted portion is temporarily inserted into the tubular portion, and after the cooling of the fixed member, the inserted portion is further pushed into the tubular portion to insert the entire inserted portion into the tubular portion to provide a method for manufacturing a conjugate. 【0018】 As a first conjugate, the present invention provides a solid base member made of a metal material, having a main portion and an inserted portion extending from the main portion, and a fixed member made of a TiNi-based shape memory alloy material different from the metal material, the fixed member having a tubular portion clamped and fixed to the inserted portion of the base member by utilizing the superelasticity of the fixed member 【0019】 As a second conjugate, the present invention provides a first conjugate, wherein the base member is made of a linear spring material to provide a conjugate. 【0020】 The present invention provides a third bond, which is a second bond, The aforementioned assembly is a guide wire, The base member is a wire made of the spring material. Provides a composite. 【0021】 The present invention provides a fourth bond, which is any of the first to third bondes, Within the tubular portion, there is a cavity beyond the tip of the portion to be inserted. Provides a composite. 【0022】 The present invention provides a fifth bonding body which is any of the first to fourth bonding bodies, The main portion of the base member has a predetermined diameter. The wall thickness of the tubular portion is between 20% and 40% of the predetermined diameter. Provides a composite. 【0023】 The present invention provides a sixth bond, which is any of the first to fifth bondes, The portion to be inserted has a tapered shape that narrows towards the tip. Provides a composite. 【0024】 The present invention provides a seventh bonding body, which is any of the first to sixth bonding bodies. The base member further includes a protruding portion, The portion to be inserted extends from the main portion in a manner that tapers in a predetermined direction, The protruding portion extends from the insertion portion such that it does not exceed the main portion in a cross-section perpendicular to the predetermined direction. Provides a composite. 【0025】 Furthermore, the present invention provides an eighth bond, which is the sixth or seventh bond, The angle of inclination of the tapered shape of the insertion portion is 10 degrees or less. Provides a composite. [Effects of the Invention] 【0026】 In this invention, a bond is manufactured by using the superelasticity of a fixed member to be fastened and fixed to an insertion portion of a base member made of a metal material different from the TiNi-based shape memory alloy material, without welding or other methods, by changing the phase of the fixed member made of a TiNi-based shape memory alloy material. Therefore, according to this invention, it is possible to obtain a bond with high bonding strength by suppressing the formation of oxide films at the bonding interface. [Brief explanation of the drawing] 【0027】 [Figure 1] Figure 1(a) is a schematic perspective view showing a composite according to an embodiment of the present invention, and Figure 1(b) is a cross-sectional view showing the composite of Figure 1(a). [Figure 2] Figure 1 is an exploded perspective view of the combined structure. [Figure 3] This figure shows the state of the composite during the manufacturing process. [Figure 4] This is a schematic perspective view showing the combined body according to the first modified example. [Figure 5] This figure shows the state of the composite during the manufacturing process. [Figure 6] This is a schematic cross-sectional view showing the combined body according to the second modified example. [Figure 7] Figure 6 is a schematic perspective view showing the base material included in the composite. [Figure 8] Figure 8(a) is a schematic perspective view showing the combined body according to the third modification, and Figure 8(b) is a cross-sectional view showing the combined body in Figure 8(a). [Figure 9] Figure 8 is a schematic perspective view showing the tip members included in the composite structure. [Figure 10] This figure shows the state of the composite during the manufacturing process. [Figure 11] Figure 8 is a graph showing the tensile test results when a wire made of Ti-51at%Ni alloy treated at 500°C was used as the tip component. [Figure 12] This graph shows the tensile test results when piano wire is used as the base material in Figure 1. [Modes for carrying out the invention] 【0028】 Referring to Figures 1 and 2, the assembly 1 according to an embodiment of the present invention comprises a fixed member 10 made of a TiNi-based shape memory alloy material and a solid base member 20 made of a metal material different from the TiNi-based shape memory alloy material. In this embodiment, the base member 20 is a wire made of linear spring material, and the assembly 1 is a guide wire for a catheter. However, the present invention is not limited to guide wires and can be applied to assembly bodies other than guide wires. Furthermore, the present invention is easily applicable when the base member 20 is made of linear spring material, but the base member 20 does not have to be linear or made of spring material, as long as the fixed member 10 can be connected to the base member 20 as described later. 【0029】 The fixed member 10 has a tubular portion 12. The base member 20 has a main portion 22 and an insertion portion 24 extending from the main portion. Considering processability and workability, when the diameter of the main portion 22 of the base member 20 is set to a predetermined diameter, it is preferable that the wall thickness of the tubular portion 12 in the pre-manufacturing state, as described later, is 20% to 40% of that predetermined diameter. 【0030】 The tubular portion 12 of the fixed member 10 is tightened and fixed to the insertion portion 24 of the base member 20 by utilizing the superelasticity of the fixed member 10, thereby joining the fixed member 10 to the base member 20 without welding or other means. Due to this method of joining, a cavity 40 exists inside the tubular portion 12 beyond the tip of the insertion portion 24. 【0031】 In particular, the insertable portion 24 in this embodiment has a tapered shape that narrows towards the tip. Here, the angle of inclination of the tapered shape of the insertable portion 24 in this embodiment is 10 degrees or less. Considering ease of insertion, a smaller angle of inclination is preferable, and if the angle of inclination is small and the length of the insertable portion 24 is long, the contact area between the insertable portion 24 and the tubular portion 12 after insertion can be increased. 【0032】 The composite of this embodiment described above is manufactured as follows. First, the fixed member 10, made of a TiNi-based shape memory alloy material, is cooled to the martensite phase. In this state, the insertion portion 24 of the base member 20, made of a metal material different from the TiNi-based shape memory alloy material, is inserted into the tubular portion 12 of the fixed member 10. With the insertion portion 24 inserted into the tubular portion 12, the environment is changed from cooling to room temperature, thereby returning the fixed member 10 to the austenite phase. This utilizes the superelasticity of the fixed member 10 to tighten and fix the tubular portion 12 to the insertion portion 24. 【0033】 In this embodiment, before the fixed member 10 is cooled to the martensite phase and the insertion portion 24 is inserted into the tubular portion 12, the largest outer circumference of the insertion portion 24 is larger than the inner circumference of the tubular portion 12. During insertion, the insertion portion 24 expands the lumen of the tubular portion 12 at least temporarily. As a result, when the material is returned to the austenite phase, the tubular portion 12 is more firmly tightened and fixed to the insertion portion 24. 【0034】 In particular, as in this embodiment, when the portion to be inserted 24 has a tapered shape that narrows towards the tip, as shown in Figure 3, a portion of the portion to be inserted 24 may first be temporarily inserted into the tubular portion 12 at room temperature. In this state, the tubular portion 12 and the portion to be inserted 24 may be further reduced in diameter by swaging or the like. 【0035】 In the fixed member 10 and base member 20 shown in Figure 3, the insertion portion 24 is inserted into the tubular portion 12 as far as possible, and in this state, there is a distance L1 from the boundary portion B1 between the main portion 22 and the insertion portion 24 to one end (rear end) of the tubular portion 12. In this state, with a portion of the insertion portion 24 temporarily inserted into the tubular portion 12, the fixed member 10 is cooled. When the fixed member 10 is cooled to the martensite phase state, the fixed member 10 becomes a flexible structure that is easily deformable, so the insertion portion 24 can be pushed further into the tubular portion 12. Specifically, the insertion portion 24 is pushed into the tubular portion 12 until one end of the tubular portion 12 reaches the boundary portion B1 between the main portion 22 and the insertion portion 24, thereby inserting the entire insertion portion 24 into the tubular portion 12. Subsequently, when left at room temperature, the tubular portion 12 shrinks in an attempt to return to the austenite phase and recover its shape, thereby tightening and fixing the tubular portion 12 to the inserted portion 24. As is clear from this explanation, the length of the inserted portion 24 pushed into the tubular portion 12 in the martensite phase state becomes the distance L1. The longer the distance L1, the greater the total contact area on the inserted portion 24 that the tubular portion 12 tightens and fixes when it returns to the austenite phase. Therefore, the longer the distance L1, the more reliable the bond between the fixed member 10 and the base member 20 can be. 【0036】 As described above, in this embodiment, by changing the phase of the fixed member 10 made of a TiNi-based shape memory alloy material, the tubular portion 12 of the fixed member 10 is tightened and fixed to the insertion portion 24 of the base member 20 made of a metal material different from the TiNi-based shape memory alloy material by utilizing the superelasticity of the fixed member 10 without welding or the like, thereby manufacturing the bonded body 1. Therefore, according to this embodiment, it is possible to obtain a bonded body 1 that has high bonding strength by suppressing the formation of an oxide film at the bonding interface. 【0037】 The composite body 1 according to the above-described embodiment of the present invention can be modified in various ways, as illustrated below. In the following, the same reference numerals will be used for components identical to those in the above-described embodiment, and their descriptions will be omitted. Similarly, the same reference numerals will be used for components similar to those in the above-described embodiment, and their descriptions will be simplified. 【0038】 Referring to Figure 4, the fixed member 10A of the joint 1A according to the first modification has an extended portion 14A that extends further forward from the tubular portion 12A in addition to the tubular portion 12A. The joint 1A according to the first modification is obtained, for example, by preparing a fixed member 10A having a longer tubular portion 12A, and after tightening and fixing the tubular portion 12A to the insertion portion 24 of the base member 20 as in the embodiment described above (see Figure 1), the tip of the tubular portion 12A is inserted into a wire drawing die 50 and drawn, and the portion beyond the tapered extended portion 14A is cut off as shown in Figure 5. According to this method, the tightening of the tubular portion 12A to the insertion portion 24 is strengthened during the wire drawing process, and the reliability of the joint can be improved. 【0039】 Referring to Figures 6 and 7, the base member 20B of the second modified assembly 1B further has a protrusion 26B. The insertion portion 24B extends from the main portion 22 in a tapering manner along a predetermined direction, and the protrusion 26B protrudes from the insertion portion 24B such that it does not exceed the main portion 22 in a cross section perpendicular to the predetermined direction. When such a protrusion 26B is provided, the protrusion 26 bites into the tubular portion 12 when the tubular portion 12 is tightened and fixed to the insertion portion 24B, thereby increasing the reliability of the connection of the fixed member 10 to the base member 20A. However, if the protrusion 26B is large enough to protrude beyond the main portion 22, the portion of the tubular portion 12 corresponding to the protrusion 26B will protrude extremely outward due to the protrusion 26B. If large irregularities are formed on the surface in this way, it is not suitable for applications such as catheter guide wires. Therefore, it is preferable that the protruding portion 26B does not exceed the main portion 22 in a cross-section perpendicular to the predetermined direction. 【0040】 Referring to Figure 8, the composite body 1C according to the third modification is obtained by further integrating a tip member 30 to the composite body 1 according to the embodiment of Figure 1 described above. As shown in Figures 8 and 9, the tip member 30 comprises a front portion 32 and a rear portion 34. The front portion 32 has a shape that tapers towards the front and then becomes even smaller in diameter, while the rear portion 34 has a shape that tapers towards the rear. The tip member 30 according to this embodiment is made of the same material as the fixed member 10, but the present invention is not limited thereto. 【0041】 The tip member 30 is inserted into the tubular portion 12 of the fixed member 10 in the same manner as the base member 20 described above, and then tightened and fixed. Specifically, as shown in Figure 10, first, a portion of the rear portion 34 is temporarily inserted into the tubular portion 12 at room temperature. At this point, the tubular portion 12 and the rear portion 34 may be further reduced in diameter by swaging or the like. In the fixed member 10 and tip member 30 shown in Figure 10, the rear portion 34 is inserted into the tubular portion 12 as far as it can be inserted, and in this state, there is a distance L2 from the boundary portion B2 between the front portion 32 and the rear portion 34 to the other end (front end) of the tubular portion 12. With the rear portion 34 temporarily inserted into the tubular portion 12 in this state, the fixed member 10 is cooled. When the fixed member 10 is cooled to the martensite phase state, the fixed member 10 becomes a flexible structure that is easily deformable, so the rear portion 34 can be further pushed into the tubular portion 12. Specifically, the rear portion 34 is pushed into the tubular portion 12 until one end of the tubular portion 12 reaches the boundary portion B2 between the front portion 32 and the rear portion 34, thereby allowing the entire rear portion 34 to be inserted into the tubular portion 12. After that, when left at room temperature, the tubular portion 12 shrinks in an attempt to return to the austenite phase and recover its shape, so the tubular portion 12 is tightened and fixed to the rear portion 34. As is clear from this explanation, the length of the rear portion 34 pushed into the tubular portion 12 in the martensite phase state becomes the distance L2. The longer the distance L2, the greater the total contact area on the rear portion 34 that is tightened and fixed when the tubular portion 12 returns to the austenite phase. Therefore, the longer the distance L2, the more reliable the bond between the tip member 30 and the fixed member 10 can be. 【0042】 (Example 1 and Comparative Examples 1-3) Samples 1 to 4 were prepared to evaluate the composite 1 according to the embodiment shown in Figure 1. Sample 1 is Comparative Example 1, Sample 2 is Comparative Example 2, Sample 3 is Example 1, and Sample 4 is Comparative Example 3. 【0043】 In detail, a Ti-51at%Ni alloy was used as the fixed member 10. The alloy bar material was hollowed out using a gun drill to create a hollow structure with an outer diameter of 20 mm, a wall thickness of 2.5 mm, and a length of 200 mm. This was then rolled and die-drawn to form a tube shape with an outer diameter of 0.5 mm and a wall thickness of 0.1 mm. After solution treatment at 700°C, a tubular section 12 with a length of approximately 100 mm was formed. 【0044】 On the other hand, as the base member 20, a commercially available piano wire with a diameter of 0.3 mm made of high-strength carbon steel SW-A was used, and one end was tapered to form the insertion portion 24. 【0045】 Next, as shown in Figure 3, a portion of the insertion portion 24 of the base member 20 was temporarily inserted into one end of the fixed member 10 (tubular portion 12). At this point, in Example 1, the distance L1 from the boundary portion B1 between the main portion 22 of the base member 20 and the insertion portion 24 to the fixed member 10 (tubular portion 12) was set to 50 mm, while in Comparative Examples 1 and 2, the distance L1 was set to 0 mm and 20 mm, respectively. Furthermore, in Comparative Example 3, the distance L1 was set to 0 mm, but a silicone resin adhesive was injected into the tubular portion 12. 【0046】 Next, a 500°C superelastic treatment was performed to make the entire length straight. Subsequently, the fixed member 10 (tubular portion 12) and the insertion portion 24 of the base member 20 were cooled to below freezing point with dry ice. This cooling caused loosening between the fixed member 10 (tubular portion 12) and the insertion portion 24 of the base member 20 due to the thermal expansion and contraction effects of the respective metal materials. 【0047】 The fixed member 10 (tubular portion 12) has become a flexible shape-memory structure due to cooling with dry ice. In this state, the lumen of the tubular portion 12 was expanded until the distance L1, which was 0 mm during the initial insertion, while the inserted portion 24 was further pushed into the tubular portion 12. Note that in Comparative Examples 1 and 3, the distance L1 was originally 0 mm, so no further pushing was performed. Next, by leaving it at room temperature, the tubular portion 12 and the inserted portion 24 were bonded together by the shape recovery shrinkage of the fixed member 10 and the thermal expansion of the base member 20. 【0048】 (Example 2 and Comparative Example 4) Samples 5 and 6 were prepared to evaluate the composite according to the third modified example shown in Figure 8. Sample 5 is Comparative Example 4, and Sample 6 is Example 2. 【0049】 In detail, a Ti-51at%Ni alloy was used as the fixed member 10. The alloy bar material was hollowed out using a gun drill to create a hollow structure with an outer diameter of 20 mm, a wall thickness of 2.5 mm, and a length of 200 mm. This was then rolled and die-drawn to form a tube shape with an outer diameter of 0.5 mm and a wall thickness of 0.1 mm. After solution treatment at 700°C, a tubular section 12 with a length of approximately 100 mm was formed. 【0050】 Furthermore, a commercially available piano wire with a diameter of 0.3 mm made of high-strength carbon steel SW-A was used as the base member 20, and one end was tapered to form the insertion portion 24. 【0051】 Furthermore, as the tip member 30, an alloy bar material similar to that of the fixed member 10 is used to form a front portion 32 having a maximum diameter of 0.3 mm and a tapered shape with a diameter of approximately 0.1 mm for about 50 mm from one end, by repeated hot rolling, wire drawing, and annealing. At the same time, a tapered rear portion 34 is formed at the other end that is inserted into the fixed member 10. 【0052】 Next, as shown in Figure 3, a portion of the insertion portion 24 of the base member 20 was temporarily inserted into one end of the fixed member 10 (tubular portion 12), while as shown in Figure 10, a portion of the rear portion 34 of the tip member 30 was temporarily inserted into the other end of the fixed member 10. At this point, in both Example 2 and Comparative Example 4, the distance L1 from the boundary portion B1 between the main portion 22 and the insertion portion 24 of the base member 20 to the fixed member 10 (tubular portion 12) was set to 50 mm. On the other hand, in Example 2, the distance L2 from the boundary portion B2 between the front portion 32 and the rear portion 34 of the tip member 30 to the fixed member 10 (tubular portion 12) was set to 50 mm, while in Comparative Example 4, the distance L2 was set to 20 mm. 【0053】 Next, a 500°C superelastic treatment was performed to make the entire length straight. Subsequently, the fixed member 10 (tubular portion 12), the insertion portion 24 of the base member 20, and the rear side portion 34 of the tip member 30 were cooled to below freezing point with dry ice. This cooling caused loosening between the fixed member 10 (tubular portion 12) and the insertion portion 24 due to the thermal expansion and contraction effects of each metal material. 【0054】 The fixed member 10 (tubular portion 12) has become a flexible shape-memory structure due to cooling with dry ice. In this state, the lumen of the tubular portion 12 was expanded from a distance L1 during the initial insertion to 0 mm while the inserted portion 24 was further pushed into the tubular portion 12, while the lumen of the tubular portion 12 was expanded from a distance L2 to 0 mm while the rear portion 34 was further pushed into the tubular portion 12. Next, by leaving it at room temperature, the tubular portion 12, the inserted portion 24, and the rear portion 34 were joined together by the shape recovery contraction of the fixed member 10 (tubular portion 12) and the tip member 30, and the thermal expansion of the base member 20. 【0055】 Tensile tests (pull-out tests after assembly completion) were performed on each of the samples 1 to 6 (Comparative Examples 1, 2, Example 1, Comparative Examples 3, 4, and Example 2) and the metal materials used in the production process. Sample 7 is the Ti-51at%Ni alloy wire used for the tip member 30, and Sample No. 8 is the piano wire used for the base member 20. 【0056】 The results are shown in Table 1. Figure 11 shows the tensile test results for sample 7, a Ti-51at%Ni alloy wire treated at 500°C, and Figure 12 shows the tensile test results for sample 8, a piano wire. 【0057】 [Table 1] 【0058】 In the evaluation column of Table 1, the pull-out strength is 300 N / mm², based on the information disclosed in Patent Document 3. 2 The above items are marked with ○, 200 N / mm 2 The above items are △, 200 N / mm 2 The results of judging items less than a certain value as "×" are shown. 【0059】 Sample 1 (Comparative Example 1) had a distance L1 of 0 mm, resulting in no indentation under cooling and thus insufficient tensile strength. However, as with Sample 4 (Comparative Example 3), sufficient pull-out strength could be achieved by injecting an adhesive such as a silicone resin adhesive. Furthermore, the pull-out strength of Sample 2 (Comparative Example 2), with a distance L1 of 20 mm, and Sample 5 (Comparative Example 4), with a distance L2 of 20 mm, was 200 N / mm². 2 Based on the above, the pull-out strength of sample 3 (Example 1) with a distance L1 of 50 mm and sample 6 (Example 2) with both distances L1 and L2 of 50 mm is 300 N / mm². 2 That was all. 【0060】 From the above, it is understood that by increasing the distances L1 and L2 during temporary insertion, the tightening force on the base member 20 and tip member 30 can be increased due to the shape memory effect of the fixed member 10 during subsequent processing. In the evaluation described above, distances L1 and L2 were deemed sufficient at 50 mm for practical purposes, but their lengths can be appropriately selected depending on the material properties and configuration used in the device. 【0061】 In the embodiments described above, the surface roughness of the fixed member 10 and the base member 20 is preferably mesh #500 or less. However, if the surface roughness is set to, for example, mesh #100 or less, the pull-out strength will be further increased, so the surface roughness may be adjusted as needed. 【0062】 In the embodiments described above, Ti-51at%Ni alloy was exemplified as the TiNi-based shape memory alloy material used for the fixed member 10 and the tip member 30. However, a Ti-50at%Ni alloy, which has better processability, may also be used. Alternatively, a Ti-Ni alloy containing 40at% to 60at% Ti and the remainder being Ni, or a Ti-Ni-X alloy in which a portion of the Ni or Ti in the Ti-Ni alloy is replaced with one or more of the following: Cu, Fe, Cr, Al, V, Pd, Ag, Mn, Co, Nb, Hf, or Zr, may also be used. Furthermore, different TiNi-based alloys may be used for the fixed member 10 and the tip member 30. 【0063】 For example, by making the tip portion of the guide wire, such as the fixed member 10 or the tip member 30, out of a Ti-50at%Ni alloy, it is possible to provide a flexible, superelastic guide wire that can be easily deformed as needed, such as by bending the tip portion. 【0064】 For example, Ti-51at%Ni alloy can be made superelastic at room temperature by repeatedly annealing it with a reduction rate of 30-40% and then treating it at 500°C. On the other hand, Ti-50at%Ni alloy has shape memory at room temperature under normal processing / treatment, but becomes superelastic at room temperature by processing it with a reduction rate of slightly more than 60% and then treating it at 300°C-400°C. 【0065】 In the embodiments described above, the superelastic treatment temperature of the Ti-51at%Ni alloy material after temporary insertion was set to 500°C, but it is acceptable to set it to 1000°C or lower, and preferably to 300°C to 500°C, including the Ti-50at%Ni alloy. 【0066】 In the embodiments described above, piano wire was used as the base member 20, but any spring material selected from stainless steel, Fe-based alloy, Ni-based alloy, Ti-based alloy, or Cu-based alloy, excluding the material constituting the fixed member 10, may be used. 【0067】 As described above, according to the present invention, by utilizing the shape memory effect and superelasticity of a tubular TiNi-based shape memory alloy material, it becomes easier to bond a fixed member made of a TiNi-based shape memory alloy material to a base member made of a different metal material. 【0068】 Furthermore, according to the present invention, there is no need to design considering factors that degrade properties, such as oxides generated during conventional bonding interface melting. 【0069】 Although the present invention has been described in detail above with reference to embodiments, the present invention is not limited thereto. As will be obvious to those skilled in the art, the embodiments can be modified without departing from the spirit of the invention, and such embodiments fall within the scope of the present invention. [Explanation of Symbols] 【0070】 1,1A,1B,1C conjugate 10,10A Fixed member 12,12A tubular part 14A Extension 20,20B Base member 22 Main part 24,24B Inserted part 26B Protrusion 30 Tip member 32 Front side 34 Rear side 40 hollow 50 wire drawing dies

Claims

[Claim 1] A fixed member made of a TiNi-based shape memory alloy material, having a tubular portion, is cooled to a martensite phase state. A portion of a solid base member made of a metal material different from the TiNi-based shape memory alloy material is inserted into the tubular portion. By returning the fixed member to the austenite phase at room temperature, the superelasticity of the fixed member is used to tighten and fix the tubular portion to the insertion portion. After the tightening and fixing process, the portion of the fixed member including the tubular part is drawn using a wire drawing die. A method for manufacturing a compound. [Claim 2] A method for manufacturing the compound according to claim 1, When inserting the part to be inserted into the tubular part, the part to be inserted is pushed into the tubular part so as to expand the lumen of the tubular part until one end of the tubular part reaches the boundary between the main part of the base member, which has a constant diameter along a predetermined direction, and the part to be inserted, which has a tapered shape that narrows from the main part along the predetermined direction. With one end of the tubular portion reaching the boundary portion, the fixed member is returned to the austenite phase. A method for manufacturing a compound. [Claim 3] A method for manufacturing the composite according to claim 1 or claim 2, The base member further comprises a protruding portion that extends from the portion to be inserted, When the tubular portion is tightened and fixed to the portion to be inserted, the protruding portion bites into the tubular portion. A method for manufacturing a compound. [Claim 4] A method for manufacturing a composite according to any one of claims 1 to 3, The portion to be inserted has a tapered shape that narrows towards the tip. The cooling of the fixed member is performed with a portion of the insertion part temporarily inserted into the tubular portion. After the fixed member has cooled, the insertion portion is further pushed into the tubular portion, thereby inserting the entire insertion portion into the tubular portion. A method for manufacturing a compound. [Claim 5] A solid base member made of a metal material, having a main part and an insertion part extending from the main part, The fixed member comprises a TiNi-based shape memory alloy material different from the aforementioned metal material, and having a tubular portion that is tightened and fixed to the insertion portion of the base member by utilizing the superelasticity of the fixed member, The fixed member has a drawn extension portion extending from the tubular portion. conjugate. [Claim 6] The composite according to claim 5, The main portion of the base member has a predetermined diameter. The wall thickness of the tubular portion is 20% to 40% of the predetermined diameter. conjugate. [Claim 7] The composite according to claim 5 or claim 6, The base member further includes a protruding portion that extends from the portion to be inserted, Because the inserted portion is tightened against the tubular portion, the protruding portion is biting into the tubular portion. conjugate.

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