JPS62189423A - Material for spectacle frame and its production - Google Patents

Abstract

PURPOSE:To permit brazing with high strength and to improve platability as well by forming a titled material of a 3-layered clad material interposed with an Mo layer between a core material consisting of Ti or Ti alloy and the outermost layer consisting of Ni or Ni alloy. CONSTITUTION:The 3-layered clad material 4 consisting of the Ti or Ti alloy as the core material 1, the Mo layer as the intermediate material 2 and the Ni or Ni alloy as the outermost layer 3 is used as the material for a spectacle frame. The manufacture of the clad stock is executed by preparing the core material consisting of the Ti or Ti alloy and a hollow material consisting of the Ni or Ni alloy, degreasing and cleaning the two metallic materials with a trichloroethylene, etc., winding Mo foil on the core material, fitting the two materials and subjecting the same to vacuum evacuation or substn. with an inert gas and hermetically joining the end faces. The clad stock is then subjected to hot stretching to stretch the stock. Hoe extrusion and cross helical rolling are combined in the stretching.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a material for eyeglass frames and a method for manufacturing the same;
In particular, the present invention relates to a material for eyeglass frames comprising a three-layer clad material in which a Mo layer and a Ni or Ni alloy layer are clad and pressure-bonded to a Ti or Ti alloy core material, and a method for manufacturing the same.

(Conventional technology)? + is a material with excellent corrosion resistance, workability, etc., and is also lightweight, so it has recently been used in large quantities as a material for metal frames for high-grade Xanglass. However, Ti alone has the drawback of poor brazing and plating properties. Development is underway to address these shortcomings with special techniques and equipment, but it goes without saying that as long as Ti itself is the target, more special equipment and techniques than conventional techniques must be used. Ti has a high material cost to begin with, and when you add in the equipment costs, it becomes a very expensive material.

By the way, in order to improve the drawbacks of the above-mentioned single Ti wire, we have developed a wire rod in which Ni or a Ni-based alloy with good brazing and plating properties is clad and crimped on the surface of Ti (Utility Model Application Publication No. 56-50629) and Its manufacturing method (Tokuko Showa 6)
No. 0-13424 and Japanese Unexamined Patent Publication No. 57-156879) have been proposed. However, in this cladding material, Ti and Ni are mixed into TiJi due to metal diffusion at the cladding interface.
% TlNi5 Since brittle intermetallic compounds such as TiNi3 are generated, there is a problem that the bonding strength at the cladding interface is reduced. If the bond strength decreases, the core material and outer layer material may separate during the wire drawing process, the core material and outer layer material may separate during processing into eyeglass frames and other parts, and even when brazing the eyeglass frame assembly. A problem occurs in which the core material and outer layer material peel off.

(Problems to be Solved by the Invention) The purpose of the present invention is to improve the above-mentioned drawbacks of conventional Ti wires or clamped Ti wires, improve joint strength, and enable high-strength brazing. Ti with good plating properties
Another object of the present invention is to provide a material for eyeglass frames using a Ti alloy as a core material and a method for manufacturing the same.

(Means for Solving the Problems) That is, the present invention provides eyeglasses made of a three-layer cladding material in which 30 layers exist between a core material made of Ti or Ti alloy and an outermost layer made of old or Ni alloy. It is a frame material.

Furthermore, in the present invention, the core material of Ti or Ti alloy is M.

The outermost layer is coated and sealed with Ni or Ni alloy through an intermediate material of the layer, and the inside of the coating is made into a vacuum state or the air inside the coating is replaced with an inert gas to form a cladding material,
The clad material is heated to a temperature of 850° C. or less to perform hot extrusion processing, then heated to a temperature of 850° C. or less and subjected to inclined rolling in an inclined rolling mill, and then, for example, several times. By repeating die wire drawing and softening annealing several times,
This is a method for producing an eyeglass frame material, which further comprises cold stretching.

The eyeglass frame material manufactured in this way is then shaped into an eyeglass frame by frame component processing and brazing. Further, if desired, plating is performed as appropriate to produce a product.

Thus, according to the present invention, there is no particular temperature limit for the above-mentioned cold drawing process, for example, the softening annealing performed in the cold wire drawing process (and a sufficient degree of softening can be achieved.In this respect, conventional drawing process The annealing temperature in the wire process is, for example, 300 to 600
℃, the conventional wire drawing line speed (furnace time is about 2
sufficient softening annealing was not achieved in the In Japanese Patent Publication No. 60-13424, the softening annealing treatment is performed by subjecting the wire rod to a temperature of 300 to 600°C, for example, 450°C for 2 hours or 5 hours.
This is carried out by heat treatment at 50° C. for 30 minutes and further at 600° C. for less than Mo. However, in the present invention, even if the annealing temperature is as high as 700°C, embrittlement due to intermetallic compounds is not a problem, so high temperature and short time processing is possible, which reduces productivity even in the actual wire drawing process. It is possible to ensure softening annealing of the material without causing any damage. In the conventional method (Japanese Patent Publication No. 60-13424), the speed of the wire drawing line had to be reduced in order to soften and anneal the material.

Furthermore, the above “extrusion”-“incline rolling” according to the present invention→
According to the "dice wire drawing" process, there is no uneven thickness of the cladding layer, and an excellent concentric cladding material can be manufactured. As a result, even when processed into a complicated shape, the cladding layer does not peel off and exhibits good processability.

(Function) Next, the present invention will be explained in more detail based on specific embodiments thereof.

FIG. 1 schematically shows a cross section of the eyeglass frame material according to the present invention, and as shown in the figure, according to the present invention, T
i or Ti alloy as the core material 1, a Mo layer as the intermediate material 2,
A three-layer cladding material 4 made of Nt or Ni alloy is used for the outermost layer 3 as a material for eyeglass frames, but the reason why a Mo layer is used as an intermediate material is to thin the diffusion layer formed by the intermetallic compound of Ti and Ni. It is necessary for Furthermore, Mo
Since the intermediate layer is provided, the restriction on the annealing temperature in the die wire drawing step in the manufacturing process is relaxed as described above.

The thickness of the Mo layer is usually 0.5 to 1.5/2 in the final product.
III is sufficient, but there is no particular restriction. Also N
It is sufficient that the i or Ni-based alloy layer has a thickness of 0.1 to 0.3'mm.

In the present invention, when making a cladding material, a core material of Ti or Ti alloy and a hollow material of Ni or Ni alloy are prepared, and after degreasing and cleaning both metal materials with Triclean, etc., FIofQ is wrapped around the core material. After that, the two are fitted, and the end faces are hermetically joined by evacuating or replacing with inert gas. Alternatively, the processing order is changed, and a core material coated with MoF3 is inserted into a hollow material that has been evacuated or replaced with an inert gas, and then the end faces are hermetically joined to form a cladding material. This preparation of the cladding material is done in order to avoid forming an oxide film on the interface during heating in the next step.

Next, a hot (warm) stretching process is performed to stretch the clad material. The present invention is characterized in that this hot (warm) stretching process combines "hot extrusion" and "incline rolling" processes. This is because hot extrusion processing alone cannot
This is because the bonding strength is as low as Mo~14 kg/ml, and furthermore, if a size that can be cold-worked is attempted, there will inevitably be restrictions on the size of the material. This is because if you try to increase the area reduction rate by increasing the size of the material, the press machine itself will become very large. In addition, Ti or Ti alloy is the core material and Ni is the outermost layer material.
Alternatively, due to the large difference in deformation resistance from Ni alloy, it is not possible to obtain a very large reduction in area by hot extrusion. Therefore, in the present invention, the hot extrusion process is followed by cross-type inclined rolling.

On the other hand, with only inclined rolling, when the fitted cladding material is inclined rolled, a condition called flaring, which is unique to inclined rolling, occurs where only the outermost layer material is stretched, resulting in a phenomenon in which the core material and the outermost layer material separate. Therefore, the present invention employs a processing method that combines hot extrusion and inclined rolling.

In addition, in the above-mentioned hot stretching method, it is recommended to adopt the generally used groove rolling method, that is, a stretching process using only groove rolling, or hot extrusion followed by groove rolling. It is also possible to adopt a stretching process called rolling. However, in the groove rolling method, a constrained surface and a free surface always exist, and a phenomenon occurs in which the boundary surface is ItJIH on the free surface.

The present inventor investigated the two types of hot stretching processes described above using the groove rolling method, but upon microscopic observation of the interface of the finished product, it was confirmed that there were some points of poor bonding.

Furthermore, in the hot drawing process of the present invention, a hot forging method can be used instead of the groove rolling method discussed above, but the result is a phenomenon in which the boundary surface peels off, similar to the case of groove rolling. occurred.

Therefore, from the above, the hot (warm) stretching method in the present invention is "hot extrusion", preferably "
It was confirmed that it is necessary to combine hot extrusion J using a press with "incline rolling using an inclined rolling mill", preferably "inclining rolling using a cross-type inclined rolling mill".

Here, "rflJ1 skew rolling" means to rotate three or four rolls of the same shape at the same speed in the same direction with their axes tilted at a certain angle with respect to the material axis, and to apply a feed rate to the material. This is a method of processing by giving Also, “cross-type”
This refers to the case where the axes of the rolls are arranged so as to intersect each other with respect to the material axis.

As the cross-type inclined rolling method, it is desirable to adopt the method proposed by the present inventors (Japanese Unexamined Patent Publication No. 59-4902), but the method is not particularly limited thereto.

In the hot (?IJL) stretching method, the heating temperature is set to 850°C or lower because Ti reacts with other metals such as Ni and Cu and begins to melt at around 900°C. This is because "hot extrusion" and "incline rolling" adopted in the present invention can increase the degree of processing (area reduction rate), so processing heat is generated during processing, and the
This is because the material temperature increases by about ℃. Therefore, the heating temperature was set to 850°C or less. The lower limit of this heating temperature is not particularly limited as long as so-called hot working (or warm working) is performed, but in general, it is preferably 500°C or higher in the case of hot extrusion processing, and 500°C or higher in the case of inclined rolling processing. In this case, the temperature is 400'C or higher.

Next, the hot-stretched clad material thus IJed is cold-stretched to form a predetermined wire rod, and die wire drawing is typically used in this cold-stretching step. Die drawing is preferably necessary to maintain the concentric cladding shape obtained in the hot drawing step.

When cold stretching is performed by groove rolling, the concentric shape of the cladding material may become severely distorted as shown in Figure 1, and in that case, the outermost layer may be torn during the next frame part processing process. Trouble occurs.

The eyeglass frame material produced in this manner usually has a diameter of about 2 to 3III, and is cut into appropriate dimensions, bent into a predetermined shape, and then assembled into an eyeglass frame by brazing.

In addition, the core material includes Ti and Ti alloys, but in that case, in addition to 4@Ti, Ti and 8Q, V, Mn, Fe5Cu, which have Ti as the main component, etc.
It contains an alloy with one or more of components such as Mo, Cr, and W, and the Ti content in the alloy is 90% (
(wt%, hereinafter the same shall apply unless otherwise specified) or more is preferable, because if it is less than 90%, the specific gravity will increase and the characteristics as a light metal will be impaired.

The material for the outermost layer includes Ni and Ni alloys, but in that case, in addition to pure Ni, Ni containing Ni as the main component and Crs CL1% Fes Ag, si, S
,, I'bb Pt, ^u2 rare earth element, Ti,
One of the components such as Nb, AQ, Mo, Sns Co, etc.
! ! ! ! Or it includes an alloy with two or more kinds.

Mo, which is an intermediate material, includes not only pure Mo but also Mo alloys, but since it is preferable to supply it in thin pieces as much as possible, it is generally used in the form of Mo alone or in the form of foil.

Next, the present invention will be explained in more detail by way of examples.

Example (1) Evaluation of bonding strength: Material A: Polished outer periphery, outer diameter 69 mm x length 2
0011II pure Ti rod (JIS 2Tffi)
M.

Outer diameter 784m x thickness 4. After coating with foil and polishing the inner surface. After degreasing and cleaning the contacting surface of a hollow Monel material having a length of 220 mm, it was inserted, vacuumed, and welded to seal the end surface with a Monel plate.

Material B: Comparative material of material A, outer layer material has a thickness of 4゜5mo+
It is Monel, and the core material is M.

Materials not coated with foil.

Material: <Pure Ti> Table 1 (Weight %) Table 2 (Weight %) Manufacturing conditions: [Hot extrusion conditions] a) i%N area ratio; diameter 78 mm - diameter 40 mm b) Heating temperature 2800 ° C. [Inclination Rolling conditions] a) Intersection angle (γ) = 5゛ Inclination angle (β) = 15゜ Roll diameter - 1171 b) Roll material = SCM440 C) Roll rotation speed w 80 rpm d) Area reduction rate: diameter 40 m + w - diameter 20 + wme) Heating temperature = 600℃ Measuring method of bonding strength: As shown in Fig. 2, the test piece 11 with the bonded portion lO left is placed on the perforated table 12, and a load (P) is applied from above to ensure that the bonded portion is on the bonding surface. The maximum V4 load PMIIX until breakage was measured and calculated as [Pmax/^] from the joint surface area.

According to the measurement results, the bonding strength of material A is 28kl! f
/nm”, material B is 24kg4/mm2, and M.

The effect of the layers was confirmed.

Furthermore, when the diffusion layer at the boundary was observed using SEW and EPM8, the expansion and layer thickness was 1 to 2 μm for the material and 2 to 3 μl for the material B.

Similarly, the effect of the Mo layer was confirmed.

Next, a material having a diameter of 20+++w was heat-treated at various temperatures to examine the effect of annealing temperature on bonding strength.

The heat treatment conditions were such that each annealing temperature was held at 450 to 800°C for 30 minutes and then air cooled.

The results are summarized in a graph in Figure 3. In the case of no Mo layer, that is, in the case of material B, the bonding strength is maintained at an annealing temperature of 650°C or lower, but deteriorates extremely at an annealing temperature of 700°C or higher. On the other hand, if there is MoJil shown as material A,
Bonding strength is maintained up to 700°C and deteriorates extremely at 800°C.

This confirmed the effect of the Mo layer.

(2) Evaluation of concentricity of clad materials: Using material A and material B obtained by hot extrusion and inclined rolling, one was subjected to groove rolling and the other was subjected to die wire drawing. That is, the above-mentioned material B having a diameter of 20 mm was drawn to a diameter of 811111 by hole rolling (cold), and then drawn to a long diameter by die wire drawing. A comparison of the cross sections is shown in Figures 4+al and (bl), and it can be seen that by die drawing, a clean concentric cladding material can be obtained despite the absence of a Mo layer.

Of course, the presence of MoFJ in the material further improves the moldability. From this, it has been found that the manufacturing method of the present invention is very advantageous in obtaining concentric cladding materials.

(3) Evaluation of brazing properties: Next, brazing was performed by changing the materials, core material, outermost layer material, annealing temperature, and brazing temperature, and the brazing strength was measured.

The manufacturing conditions are the same as above for diameters up to 2 mm.
Diameters from 20II11 to 31 were drawn by die wire drawing.

These results are summarized in Table 3. These results show that the present invention is a manufacturing method that can provide materials with excellent brazing strength.

Table 3 □□”

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram of a three-layer clad structure according to the present invention; Fig. 2 is an explanatory diagram showing the procedure for testing bonding strength; Fig. 3 is a graph showing the relationship between bonding strength and annealing temperature; and FIG. 4 is an enlarged micrograph of the cross section of the three-layer clad material according to the present invention.

Claims (3)

[Claims] (1) Core material made of Ti or Ti alloy and Ni or N
A material for eyeglass frames characterized by having a three-layer cladding structure in which an intermediate Mo layer exists between the outermost layer made of i-alloy. (2) A Ti or Ti alloy core material is coated and sealed with the outermost layer of Ni or Ni alloy through an intermediate Mo layer, and the inside of the coating is made into a vacuum state or the air inside the coating is replaced with an inert gas. The clad material is heated to a temperature of 850° C. or lower to perform hot extrusion processing, and then heated to a temperature of 850° C. or lower and inclined rolled with an inclined rolling mill. 1. A method for producing an eyeglass frame material, which comprises further cold stretching. (3) The method according to claim 2, wherein the cold drawing process is performed by die wire drawing.