WO2007116613A1

WO2007116613A1 - Motion guide device and clad material used for motion guide device

Info

Publication number: WO2007116613A1
Application number: PCT/JP2007/053031
Authority: WO
Inventors: Yasuhiro Michiyama
Original assignee: Thk Co., Ltd.
Priority date: 2006-03-30
Filing date: 2007-02-20
Publication date: 2007-10-18
Also published as: JPWO2007116613A1

Abstract

A motion guide device has a raceway member (41) and a movement member movably mounted on the raceway member (41) with rolling bodies in between them. At least either the raceway member (41) or the movement member is made of a clad material. The clad material is formed as a composite material of a first metal material (for example, beta type titanium alloy)(61) and a second metal material (for example, an alpha type titanium alloy)(62). The first metal material (61) is harder than the second metal material (62), and at least a portion near a rolling body rolling surface (41a) in contact with the rolling bodies is preferably made of the first metal material (61). Also, the first metal material (61) is preferably constructed so as to occupy a range of 0.5 mm in depth from the surface of the rolling body rolling surface (41a).

Description

Specification

Motion guide device and clad material used in motion guide device

Technical field

TECHNICAL FIELD [0001] The present invention relates to a motion guide device and a clad material used in the motion guide device.

Further, the present invention relates to a motion guide device composed of a structural member card material.

Background art

[0002] Conventionally, in motion guide devices such as linear guides, linear guide devices, ball spline devices, and ball screw devices, the members that make up a forceful device are repeatedly rolled and accompanied by a sliding motion. The structural member is generally made of a high-hardness metal material such as high-carbon chromium bearing steel, stainless steel or case-hardened steel.

[0003] On the other hand, due to the recent demand for expanding the application range of motion guidance devices, it is desired to put into practical use a motion guidance device that can be used under various conditions. For example, in Patent Document 1 below, in order to realize a bearing that is non-magnetic and can be used in a corrosion-resistant environment, a vacuum environment, and a high-temperature environment, the inner ring and the outer ring constituting the bearing are made of a titanium alloy. This technology is disclosed. According to Patent Document 1 below, conventional titanium alloys have problems in terms of seizure, hardness, and wear resistance, so that they could not be used for rolling devices such as bearings. By optimizing the addition amount of Cr, which is an element, and 0, N, and C, which are interstitial solid solution elements, a titanium alloy having a significantly hardened α 'martensite structure that cannot be obtained with conventional titanium alloys is obtained. It is said that by controlling the quantity ratio of α and martensite, it is possible to provide a bearing for special environments that has a long life in special environments such as underwater.

[0004] In order to further improve the above-described technique, various inventions have been devised from the viewpoint of increasing the hardness of the titanium alloy (see, for example, Patent Document 2 below).

Patent Document 1: Japanese Patent Application Laid-Open No. 11 153140

Patent Document 2: Japanese Translation of Special Publication 2002-8623

Disclosure of the invention

Problems to be solved by the invention [0006] However, there is a limit to the technology for increasing the hardness of titanium alloys while exerting force, such as motion guide devices such as linear guides, linear guide devices, ball spline devices, ball screw devices, and rotary bearing devices. In that case, those using titanium alloys have not yet been mass-produced, but have been commercialized on a commercial basis.

[0007] In addition, in the rolling devices such as bearings disclosed in Patent Documents 1 and 2, the invention has been made based on the idea that the surface hardness of the titanium alloy is increased. Improving the hardness of the steel directly causes a decrease in the toughness of the titanium alloy, so there is a certain limit to the idea of improving the hardness. In addition, manufacturing a motion guide device that is structurally more complex than a rolling bearing with a titanium alloy, which is a difficult-to-process material, has a problem in terms of processing cost. It's still a cunning thing to be done.

[0008] The present invention has been made in view of the existence of the above-described problem, and among the constituent members of the motion guide device, at least one of the track member and the moving member is formed of a clad material. It is possible to adopt a metal material with a low hang rate such as titanium alloy, which was difficult to adopt with conventional motion guidance devices, and furthermore, motion guidance with new effects that could not be realized with conventional motion guidance devices. The purpose is to provide a device and to expand the application range of the motion guide device.

Means for solving the problem

[0009] The motion guide apparatus according to the present invention is a motion guide apparatus comprising a track member and a moving member that is movably attached to the track member via a plurality of rolling elements, the track member and At least one of the moving members is made of a clad material.

[0010] In the motion guide apparatus according to the present invention, the clad material is configured as a composite material of a first metal material and a second metal material, and the first metal material is the second metal material. It is preferable that the hardness is higher than that of the metal material, and at least the vicinity of the rolling element rolling contact surface that contacts the plurality of rolling elements is constituted by the first metal material.

[0011] Further, in the motion guide apparatus according to the present invention, the first metal material is an | 8-type titanium alloy or an α + j8-type titanium alloy, and the second metal material is an α-type titanium alloy. thing It can be.

[0012] Further, in the motion guide device according to the present invention, the second metal material is arranged to be a core material of the track member or the moving member, and the first metal material is the second metal material. A plurality of the metal materials may be arranged at symmetrical positions.

The clad material according to the present invention is configured as a composite material of a first metal material and a second metal material, and is attached to the race member and the race member so as to be movable via a plurality of rolling elements. The first metal material is harder than the second metal material, and is in contact with at least the plurality of rolling elements. The vicinity of the rolling element rolling surface is made of the first metal material.

[0014] In the cladding material according to the present invention, the first metal material is a β-type titanium alloy or a +8 type titanium alloy, and the second metal material is a type titanium alloy. You can.

[0015] In the clad material according to the present invention, the second metal material is arranged to be a core material of the raceway member or the moving member, and the first metal material is A plurality of the second metal materials may be arranged symmetrically with respect to the second metal material.

[0016] It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention, and a sub-combination of these feature groups can also be an invention.

The invention's effect

[0017] According to the present invention, since at least one of the track member and the moving member is made of the clad material, a completely new driving guide device capable of exerting a powerful function that cannot be realized conventionally is provided. be able to.

[0018] Specifically, the clad material according to the present invention is configured as a composite material of a first metal material and a second metal material, and the first metal material is a second metal material. Further, the vicinity of the rolling element rolling surface that contacts at least a plurality of rolling elements is made of the first metal material having high hardness. Therefore, according to the present invention, while maintaining the function as the motion guide device by increasing the hardness in the vicinity of the rolling element rolling surface, the second metal material as the core material is subjected to correction processing because of its low hardness. Immediately as a whole, structural materials It is possible to provide an unprecedented motion guide device by using a clad material capable of exhibiting the functions as described above.

[0019] In particular, a titanium alloy that has been difficult to put into practical use by adopting a j8 type titanium alloy or α + j8 type titanium alloy as the first metal material and an α type titanium alloy as the second metal material. It is possible to realize a motion guide device made of metal. In other words, the use of a clad material that can freely determine the range occupied by the first hard metal material (β-type titanium alloy or α + j8-type titanium alloy) is a depth that was impossible in the prior art. The hardness of the titanium alloy can be improved (for example, the surface force depth of the rolling element rolling surface is in the range of 0.5 mm), and the motion guide device made of titanium alloy can be put into practical use.

[0020] Further, when one component member is made of the same titanium alloy as disclosed in the prior art such as Patent Documents 1 and 2, etc., it is necessary to improve hardness in consideration of a decrease in toughness. There was a limit (350-400HV). However, in the case of the clad material according to the present invention, it is assumed that the first metal material (β-type titanium alloy or α + j8-type titanium alloy) is hardened to the maximum (450 to 550 HV). However, since the toughness of the entire structural material can be maintained by the presence of the second metal material (a-type titanium alloy), it is possible to realize a motion guide device with a higher load and longer life than the conventional technology.

[0021] Further, in the present invention, the second metal material is disposed so as to be a core member of the raceway member or the moving member, and a plurality of the first metal materials are symmetrically arranged around the second metal material. Therefore, the strength balance of the entire structural material is stable, and it is very easy to shape the shape during processing.

Brief Description of Drawings

[0022] [FIG. 1] FIG. 1 is a model diagram used by the inventor to examine the contact state of two objects, a “sphere” and a “flat plate”, based on Hertz's theory. The contact state between the object I which is a “sphere” and the object II which is a “flat plate” is shown.

[Figure 2] Figure 2 shows the relationship between the major axis radius a, minor axis radius b, and maximum shear stress depth z.

1

is there.

FIG. 3A is an external perspective view illustrating one embodiment of a linear guide device constituted by a clad material according to the present embodiment. FIG. 3B is a cross-sectional view for explaining an infinite circuit provided in the linear guide device shown in FIG. 3A.

FIG. 4A is a side view of the track rail according to the present embodiment.

[FIG. 4B] FIG. 4B is a longitudinal sectional side view of the track rail mounting hole forming position according to the present embodiment.

FIG. 5 is a vertical cross-sectional side view showing a moving block formed by a clad material according to the present embodiment.

Explanation of symbols

[0023] 40 linear guide device, 41 track rail, 41a rolling element rolling surface, 42 balls, 43 moving block, 43a loaded rolling element rolling surface, 45 mounting hole, 52 loaded rolling path, 53 unloaded rolling path, 55 diversion path, 61, 71 first metal material, 62, 72 second metal material. BEST MODE FOR CARRYING OUT THE INVENTION

[0024] When a metal material having a low Young's modulus, such as a titanium alloy, is to be used for an exercise plan apparatus as a result of the inventor's investigation, comparing the stress generation position under the same load, the conventional V It has been found that the stress generation position is deeper than that of materials with high Young's modulus such as steel and ceramic materials.

That is, the inventor considered the contact state of two objects, “sphere” and “flat plate”, using Hertz's theory. Fig. 1 is a model diagram used in this study, showing the contact state between object I, which is a "sphere", and object II, which is a flat plate. As shown in Fig. 1, when two objects are pressed against each other with a load Q, the curved surface of the object I, which is a `` sphere '', has two principal curvature surfaces that are orthogonal to each other. The maximum and minimum curvatures of I are included. And if the radius of curvature of the curve is r, the curvature p is expressed as = lZr. Hereinafter, for the curvature p and the curvature radius r, for example, in the case of the main curvature surface 1 of the object I, the curvature p,

II

It is represented by the rate radius r. That is, the first subscript represents the object and the second subscript represents the principal curvature surface.

II

is doing.

[0026] The contact surface with which these two objects come into contact can be grasped as an ellipse (including a circle) composed of a major axis radius a and a major axis radius b. The major axis radius a and the major axis radius b can be expressed as the following formulas (A) and (B), respectively. [Number 1]

[0027] The elastic constant Θ can be expressed as an approximate expression (C).

[Equation 2] Ha 4 (m ² -l): _ 32 (Q \

'm-E' 9E

Ε,, E _u Young's modulus

1 / m: Poisson's ratio

[0028] Substituting approximate equation (C) into equations (A) and (B), respectively, μ = ν = 1, _β = lZr,

I

Since p = 0, it can be expressed as equation (D).

II

[Equation 3]

[0029] Since the object I and the object II considered this time are “sphere” and “flat plate”, respectively, a = b and the shape of the contact surface is a circle. Therefore, the contact area is π a ² , and in the above formula (D), if the compressive load Q is constant and the sphere radius is r, the Young's modulus E of object I and object II,

I

It can be seen that as E becomes lower, the major axis radius a becomes larger. In other words, a material with a low Young's modulus

II

This contact area is larger than that of a material having a high Young's modulus.

[0030] From the major axis radius a and minor axis radius b obtained as described above and the diagram shown in FIG. The breaking stress depth z can be obtained. That is, from a = b to bZa = l,

1

For example, the value of z Zb = 0.47 can be obtained. Therefore, z / a = 0.47, and the value of the maximum shear stress depth z increases as the value of a increases. Therefore, it can be confirmed that the maximum shear stress depth becomes deeper as the material has a lower Young's modulus.

[0031] From the above, when trying to use a metal material having a low Young's modulus such as a titanium alloy for the motion guide device, comparing the stress generation position under the same load, the conventional steel and ceramic materials are compared. Compared with materials with high Young's modulus, metal materials with low Young's modulus have deep stress locations, so it is necessary to design them according to their depth.

[0032] Incidentally, the conventional rolling devices such as the bearings disclosed in Patent Documents 1 and 2 are designed based on the idea of increasing the surface hardness of the titanium alloy. Processing and coating techniques are applied. However, the improvement in hardness by such surface treatment is limited to a depth of about 0.1 mm from the surface. In particular, considering the configuration of motion guide devices that are currently in practical use (for example, ball diameter and device dimensions) and the safety factor at the time of design, based on the above considerations, at least the rolling element rolling surface It is considered necessary to improve the hardness in the region from the surface to a depth of about 0.5 mm. However, at present, no surface treatment technology has been put into practical use for achieving such a depth improvement for a metal material having a low Young's modulus such as a titanium alloy.

[0033] Based on the above examination results, the inventor has invented the use of a clad material as a constituent member of the motion guide device in view of the necessity of improving the strength of the base material itself. Therefore, preferred embodiments for carrying out the present invention will be described below with reference to the drawings. The following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are essential for the solution of the invention. Not exclusively.

[0034] Note that the "motion guide device" in this specification includes, for example, rolling bearings used in general for machine tools and the like, non-lubricated bearings used in vacuum, linear guides and linear guide devices, ball spline devices, balls Such as screw device, roller screw device, cross roller ring, etc. In addition, it includes devices with all rolling and sliding motions. In the following description, application examples of the present invention when the exercise plan apparatus is configured as a linear guide apparatus will be described.

[0035] (Example of application to linear guide device)

The clad material according to the present embodiment can be applied to a motion guide device configured as a linear guide device as shown in FIGS. 3A and 3B. Here, FIG. 3A is an external perspective view illustrating one embodiment of a linear guide device constituted by the clad material according to the present embodiment. FIG. 3B is a cross-sectional view for explaining the infinite circuit provided in the linear guide device shown in FIG. 3A.

First, the configuration of the linear guide device 40 illustrated in FIGS. 3A and 3B will be described. The linear guide device 40 as the motion guide device according to this embodiment includes a track rail 41 as a track member, and a track rail. 41 is provided with a moving block 43 as a moving member slidably attached via balls 42... Installed as a number of rolling elements. The track rail 41 is a long member whose cross section perpendicular to the longitudinal direction is formed in a substantially rectangular shape, and on its surface (upper surface and both side surfaces) is a rolling element that becomes a track when the ball rolls. 41a ... is formed over the entire length of the track rail 41.

[0037] Here, the track rail 41 may be formed to extend linearly or may be formed to extend in a curved manner. In addition, the number of rolling element rolling surfaces 41a is four in total, two on each side, but the number can be changed according to the application of the linear guide device 40.

[0038] On the other hand, the moving block 43 is provided with load rolling element rolling surfaces 43a 'at positions corresponding to the rolling element rolling surfaces 41a. The rolling element rolling surface 41a 'of the track rail 41 and the load rolling element rolling surface 43a of the moving block 43 form a load rolling path 52 ..., and a plurality of balls 42 are sandwiched between them. Yes. Further, the moving block 43 includes four unloaded rolling paths 53 extending in parallel with the rolling element rolling surfaces 41 a, each unloaded rolling path 53, and each loaded rolling path 52. There is a direction change path 55 ... One endless circulation path is configured by a combination of one loaded rolling path 52 and unloaded rolling path 53 and a pair of direction changing paths 55 connecting them (see FIG. 3B). [0039] Then, a plurality of balls 42 are installed in an infinite circulation path composed of a load rolling path 52, a no-load rolling path 53, and a pair of directional switching paths 55, 55 so as to allow infinite circulation. As a result, the moving block 43 can reciprocate relative to the track rail 41.

[0040] In the linear guide device 40 according to the present embodiment having the above-described configuration, as a characteristic point, at least one force of the track rail 41 as the track member and the moving block 43 as the moving member is clad. It is mentioned that it is made of a material.

[0041] For example, a specific embodiment of the track rail 41 will be described with reference to FIGS. 4A and 4B. FIG. 4A is a side view of the track rail according to the present embodiment, and FIG. 4B is a vertical cross-sectional side view at the mounting hole forming position of the track rail according to the present embodiment.

The track rail 41 according to the present embodiment is formed of a clad material configured as a composite material of a first metal material 61 and a second metal material 62. In the present embodiment, the first metal material 61 is made of | 8 type titanium alloy, while the second metal material 62 is made of diamond titanium alloy. Of particular importance is the fact that the first metal material 61 made of | 8-type titanium alloy having high hardness is disposed in the region where the plurality of rolling element rolling surfaces 41a are formed, and the other regions. Is that the second metal material 62 having a low hardness α-type titanium alloying force is disposed.

[0043] By forming the track rail 41 according to the present embodiment with the clad material having the above-described configuration, first, the vicinity of the rolling element rolling surface 41a that is repeatedly subjected to the rolling load can be increased in hardness. It is possible to maintain the function as a motion guide device.

[0044] In addition, the first metal material (β-type titanium alloy) 61 in the vicinity of the rolling element rolling surface 41a has high hardness, and the second metal material (model titanium alloy) 62 as the core material has Due to its low hardness, for example, the second metal is maintained while maintaining the straightness of the rolling element rolling surface 41a even after the rolling material rolling surface 41a is cut by molding the clad material into the shape of the track rail 41. Since the material (model titanium alloy) 62 can be modified and the shape of the track rail 41 as a whole can be modified to the desired dimensions, etc., the machined surface of the difficult-to-work titanium alloy Can be reduced.

[0045] Further, in the case of the track rail 41, it is necessary to make a mounting hole 45 for fixed installation, but the region where the mounting hole 45 has to be drilled is the second area of low hardness. Metal Since the material (α-type titanium alloy) 62 is used, the load on the machined surface is reduced.

[0046] Furthermore, by forming the track rail 41 according to the present embodiment with a clad material as shown in Figs. 4 and 4, it is possible to construct the constituent material to a depth that was impossible with a conventional titanium alloy track rail. It is possible to improve the hardness. That is, by adopting the clad material according to the present embodiment, for example, the surface force depth of the rolling element rolling surface 41a is 0.5 mm (the depth is more than that), and the first metal has a high hardness. The material (β-type titanium alloy) 61 can be configured to occupy the material, so it is possible to improve the hardness at the depth position where shear stress is applied, and the titanium alloy motion guide device can be put to practical use. It is.

[0047] Furthermore, the use of the clad material according to the present embodiment enables a level of hardness improvement that is impossible with a conventional titanium alloy motion guide device. That is, when one component member is made of the same titanium alloy as disclosed in the prior arts such as Patent Documents 1 and 2, etc., there is a limit to improvement in hardness in consideration of a decrease in toughness ( 350-400HV). However, in the case of the clad material according to this embodiment, even if the first metal material (| 8-type titanium alloy) 61 is hardened to the maximum (450 to 550 HV), Therefore, the toughness of the entire structural material can be maintained by the presence of the metal material (a-type titanium alloy) 62. Therefore, according to the clad material according to the present embodiment, it is possible to realize a motion guide device having a higher load and a longer life as compared with the prior art.

[0048] Further, as a preferred configuration of the clad material according to the present embodiment, as shown in FIGS. 4A and 4B, a second metal material (titanium titanium alloy) 62 is used as the core material of the track rail 41. As for the first metal material (j8 type titanium alloy) 61, the first metal material is centered on the second metal material (a type titanium alloy) 62. (β-type titanium alloy) 61 is configured to be arranged at a symmetrical position. That is, in the examples of FIGS. 4 and 4A, a pair of first metal materials having the same shape on the left and right above the track rail 41 (centered on the second metal material (α-type titanium alloy) 62 ( ι8 type titanium alloy) 61 are arranged facing each other, and a pair of first metal materials (13 type titanium alloy) 61 having the same shape are arranged oppositely on the left and right sides of the track rail 41. The In this way, the first metal material (β (Titanium alloy type) 61 is placed opposite to each other, so that the strength balance of the track rail 41 as a whole is stabilized, and the shape formation during processing becomes very easy.

Note that the moving block 43 can also be formed by the clad material according to the present embodiment described above. FIG. 5 is a vertical cross-sectional side view showing a moving block formed of the clad material according to the present embodiment. As shown in FIG. 5, the moving block 43 according to the present embodiment is configured by a first metal material (| 8-type titanium alloy) 71 having high hardness in the vicinity of the loaded rolling element rolling surface 43a. However, the other parts can be made of a second metal material (a-type titanium alloy) 72 having a low hardness. In the moving block 43 illustrated in FIG. 5, the force balance in which the first metal material (| 8-type titanium alloy) 71 is arranged only in the vicinity of the loaded rolling element rolling surface 43a... In consideration of the above, it is also preferable to dispose the first metal material (| 8-type titanium alloy) 71 at a position on the outer peripheral surface side of the moving block 43 facing the loaded rolling element rolling surface 43a.

[0050] (Clad Material Manufacturing Method)

As a manufacturing method of the clad material according to the present embodiment, various methods can be adopted depending on a desired product shape, but generally used hot rolling, cold rolling, diffusion bonding, The clad material may be made after a method such as explosive pressure welding, and the forming process may be performed, or a method of manufacturing a clad material by simultaneously joining and forming dissimilar metal laminates by deep drawing. May be. In the case of the track rail 41 according to the present embodiment described above, the α-type titanium alloy and the / 3-type titanium alloy are tightly joined by brazing and heated to about 600 ° C. to reduce the rolling reduction rate from 60 to 60 ° C. A hot rolling of about 80% is performed, and then the entire shape is formed and the rolling surface 41a is cut and ground to finish the desired track rail 41.

[0051] While the preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above embodiments. Various modifications or improvements can be covered in the above embodiment.

[0052] For example, the clad material according to the present embodiment includes rolling bearings in general and non-lubricated bearings used in vacuum, linear guides and linear guide devices, ball spline devices, ball screw devices, roller screw devices, and cross roller rings. Exercise plan with any rolling 'sliding motion, such as It is possible to apply to the internal device. And, for example, the vicinity of the rolling element rolling surface of the ball screw device screw shaft or nut member, or the vicinity of the rolling element rolling surface of the spline shaft spline outer cylinder of the ball spline device is the first high hardness. It can be composed of metal material (such as 8-type titanium alloy) 61, 71, and the other parts can be composed of second metal material (such as model titanium alloy) 62, 72 with low hardness. Even in such a case, the first metal material (ι8 type titanium alloy, etc.) has a high hardness in the range of depth of 0.5mm from the surface of the rolling element rolling surface. ) 61, 71, or a plurality of first metal materials (such as titanium alloy) 61, 71 are arranged opposite to each other so as to balance strength.

[0053] In the above-described embodiment, the case where the / 3 type titanium alloy is used for the first metal materials 61 and 71 having high hardness has been described as an example. However, a + | 8 type titanium alloy is used. It is also possible to do this.

[0054] Further, for the combination of the first metal material 61, 71 and the second metal material 62, 72, only the combination of β type titanium alloy and type titanium alloy, α + β type titanium alloy and type titanium alloy. For example,

(1) Combination of austenite, martensite, ferritic stainless steel,

(2) Combination of martensitic copper and other (for example, ferrite or austenitic) copper, combination of beryllium copper or titanium copper and other (for example, pure copper, brass, bronze) copper alloy, etc. , Ivy, a combination of pure metal and alloy metal,

(3) Various combinations such as combinations of different metals such as aluminum and magnesium, iron and titanium can be employed.

[0055] Furthermore, the number of laminated first metal materials 61 and 71 and second metal materials 62 and 72 constituting the clad material may be any number.

[0056] Embodiments to which the above changes or improvements are added can also be included in the technical scope of the present invention.

Further, the descriptive power of the claims is obvious. In addition, by adopting the configuration as described above, it is possible to provide a completely new motion guide device capable of performing powerful functions that could not be realized in the past.

Claims

The scope of the claims

[1] raceway members;

A movement member that is movably attached to the track member via a plurality of rolling elements, and a motion guide device comprising:

At least one of the track member and the moving member is made of a clad material.

[2] In the exercise guidance device according to claim 1,

The cladding material is configured as a composite material of a first metal material and a second metal material,

The first metal material is harder than the second metal material, and at least the vicinity of a rolling element rolling surface that contacts the plurality of rolling elements is constituted by the first metal material. A motion guide device characterized by comprising:

[3] In the exercise guidance device according to claim 2,

The motion guide apparatus according to claim 1, wherein the first metal material is a j8 type titanium alloy or an α + j8 type titanium alloy, and the second metal material is an a type titanium alloy.

[4] The motion guide device according to claim 2 or 3,

The second metal material is arranged to be a core material of the track member or the moving member,

A plurality of the first metal materials are arranged at symmetrical positions around the second metal material.

[5] Consists of a composite material of a first metal material and a second metal material,

A clad material used in a motion guide device comprising a race member and a transfer member that is movably attached to the race member via a plurality of rolling elements,

The first metal material is harder than the second metal material, and at least the vicinity of a rolling element rolling surface that contacts the plurality of rolling elements is constituted by the first metal material. A clad material characterized by

[6] In the clad material according to claim 5,

The first metal material is a 13-type titanium alloy or an α + j8-type titanium alloy; The clad material, wherein the second metal material is an oc type titanium alloy.

In the clad material according to claim 5 or 6,

A plurality of the first metal materials are arranged at symmetrical positions with the second metal material as a center.