DE3424030A1 - Titanium alloy for decorative use - Google Patents

Abstract

In order to improve elasticity during use, and deformability during manufacture, the titanium-based alloy, which is used for fashion articles such as, for example, watches and spectacle frames, contains a prescribed amount of Ni and Cu and, in addition, preferably Al.

Description

Titanium alloy for decorative

Application The invention relates to a titanium alloy for decorative purposes Application and in particular an improved composition of a titanium alloy, which are used to decorate fashionable items such as watches, glasses frames will. The invention also relates to a watch containing such a titanium alloy and glasses frames.

To make such fashionable articles which are generally strong decorative effects, low weight and excellent corrosion resistance require are long pure titanium or titanium alloys because of their significant Corrosion resistance has been used. Require materials for such items further tough elasticity to withstand repeated bending during use, ample deformability to allow complicated shape changes in manufacture, and high spot weldability and brazeability to ensure easy and reliable Allow connection to related materials.

In spite of the excellent resistance to corrosion, pure titanium is closed soft to have tough elasticity and also quite unsuitable for sanding for surface treatment. To cover these disadvantages, the use of several (α + B) grades of titanium alloys have been proposed. Ti-6% Al-4% V Alloy is an example. But this alloy is too hard to be even Cold work and fairly poor in spot weldability and brazeability. Ti-3% Al-2.5% V alloy is another example. This alloy is better in of deformability as the first example, but its deformability is still insufficient to easily allow complicated shape change in manufacture. Again, this alloy is quite poor in spot weldability and the brazeability.

The invention is based on the task of a titanium alloy decorative application, in particular for clocks and spectacle frames, which has a better elasticity than pure titanium, and which has a richer machinability with higher spot weldability and brazeability than those previously described Titanium alloys commonly used for these items.

This object is achieved according to the invention in that titanium alloy 0.05% to 4% by weight of Ni, 0.05x to 4x by weight of Cu, 1% or less of the Weight of total impurities such as O, N, H, Fe and Co, and the rest Amount essentially contains Ti.

"S of the weight" each means percent by weight ".

In a preferred embodiment, the titanium alloy also contains 0.01% to 1% by weight of Al.

As noted earlier, the titanium alloy according to the invention contains 0.05% to 4% by weight Ni. When it is contained in the alloy in solid solution Ni strengthens the Ti matrix and thereby increases the elasticity of the alloy. However, such a gain is entirely insignificant if its proportion is proportionate drops to just under 0.05X weight. If contained more than 4X the weight Ni forms a compound with Ti, which excessively hardens the alloy and as a result, the resulting machinability is greatly deteriorated. In the conditions The elasticity and deformability of the alloy achieved optimal results, when the content ratio is in a range of 0.05% to 4% by weight. In particular, a range from 0.08 to 2.5x the weight ensures an ideal result.

Likewise, the presence of Cu in the alloy contributes more firmly Solution helps to increase elasticity.

Any content ratio below 0.05X by weight does not ensure a significant one Effect. A content ratio over 4% by weight promotes the formation of a Cu Compound with Ti, which leads to excessive hardness, which reduces ductility the resulting alloy is seriously affected. Best effects can be expected when Cu is contained at 0.05X to 4% by weight.

In particular, a range from 0.06X to 3% of the weight ensures an ideal one Result.

Al is a & phase stabilizer. An excessive share of the salary affects the machinability of the alloy at high temperatures. In the preferred embodiment of the invention is 0.01% to 1% of the weight of Al in the alloy included to increase the level of elasticity without a significant deterioration in the Increase machinability. Preferably the alloy contains 0.02X to 0.8% des Weight Al.

O, N, Fe and Co are inevitable as impurities in the alloy , the total proportion of which should preferably be as small as possible. the the allowable limit of the total proportion is 1% by weight. Any salary ratio above this limit, the workability deteriorates and makes the alloy pretty unsuitable for grinding.

Spot weldability and brazeability of the alloy is as good as that of pure Ti, as long as the proportions of Cu and Ni or Cu, Ni and Al in can be selected from the areas described above.

Diverse mechanical and procedural properties of the Titanium alloys in accordance with the invention have been tested through a number of experiments Tests confirmed in comparison with pure Ti and conventional titanium alloys. The results obtained are shown in Tables 1 and 2.

For each comparative measurement of the mechanical properties, a rectilinear test piece of 3.0mm outside diameter by vacuum melting and rolling prepared and then tempered for 30 minutes in a high purity Ar gas environment 7000 C exposed.

A rolled wire with an outer diameter of 2.6 mm was used for elasticity tests formed into a test piece tape 0.5 mm thick, 3.1 mm wide and 150 mm long. A The end of the tape was held in place and the other end was squeezed so that the Ribbon bent over 30 or 60 degrees. After releasing the pressure, the percentage of springback became (Angle of recovery / angle of bend) is calculated. The magnitude of the bending moment was also checked. In Table 2, the mark "M" shows the formation of fine cracks when pressing, while the sign "+" the formation of significant cracks when Indicates pressing.

For spot welding tests, two rolled strips 1mm thick and 30mm wide superimposed and subjected to spot welds, both surfaces were shielded by high purity Ar gas while a Cr-Cu alloy electrode 3.5 mm dot diameter was used. In Table 2, the mark "O" shows the highest excellent welds, the sign "o" indicates excellent welds, the; Sign "" "indicates acceptable welds and the sign" x "indicates unacceptable ones Welds on. Two conditions were used for spot welding. According to of the first condition A, the current was 6,000A, the pressure was 300kg, and the actuation cycle 6. According to the second condition B, the current was 7500A, the pressure was 3000kg and the Operating cycle 6.

TABLE 1 Chemical composition Mechanical properties Sample% by weight Hardness Elongation Tensile strength (Weight percent) (Hv) (%) (kg / nm²) No Ni Cu Al O, N Ti Fe, Co 1 - - - 0.2 99.8 200 29 50 III 2 0.5 0.06 - 0.2 99.28 210 27 53 3 1.0 0.06 - 0.2 99.98 225 26 55 I. 4 2.0 0.06 - 0.2 97.98 240 23 57 5 3.0 0.06 - 0.2 96.98 248 22 58 6 5.0 0.06 - 0.2 94.98 285 16 68 Iv 7 - 0.06 - 0.2 99.94 205 29 51 8 2.0 0.5 - 0.2 97.5 243 22 57 9 2.0 1.0 - 0.2 97.0 249 21 58 10 2.0 3.0 - 0.2 95.0 259 '20 59 11 2.0 5.0 - 0.2 92.8 296 15 69 IV 12 0.5 0.06 0B02 0.2 99 122 210 27 54 13 0X5 0.06 0.08 0.2 99.16 220 26 56 14 0.5 0.06 0.12 0X2 99.12 221 26 56 15 0.5 0.06 0.20 0.2 99> 04 227 25 60 16 0.5 0.06 0.36 0.2 98.88 230 24 60 II 17 0.5 0.06 0.80 0.2 98.44 270 20 67 18 1.0 0.5 0.80 0.2 97.5 '272 18 68 19 1.0 0.8 0.80 072 97a2 275 18 68 20 1.0 1.0 0.80 0.2 97.0 277 18 68 21 2.0 0.5 0.80 0X2 96.5 278 17 69 22 2.0 0.8 0.80 0t2 96X2 280 17 69 23 2.0 1.0 0.80 0.2 96.0 280 17 69 24 2.0 3.0 0.80 0.2 94.0 300. 16 72 25 2.0 5.0 '0.80 0.2 92.0 325' 12 83 26 4.0 5.0 0.80 0.2 90.0 345 10 92 27 5.0 5.0 1.2 0.2 88.6 380 9 102 IV 28 6.0 5.0 1.2 0.2 8716 395 8 110 29 6.0 6.0 1f2 0.2 86.6 400 6 120 30 6% Al-4% V-Ti 320 16 96 V Note: I - basic concept II --- preferred embodiment III --- pure Ti IV --- comparative example V - conventional alloy TABLE 2 Sample spring test spot weld test piece percent springback bending condition condition (%) moment (kg cm) No. 30% 60% 30 ° 60 ° AB 1 93 78 1.8 2.5 0 0 III 2 97 83 1.9 2.7 0 0 3 97 85 2.0 2.8 0 0 I. 4 98 88 2.1 3.0 0 0 5 99 89 2.2 3.2 0 0 6 98 89 2.4 3.3 0 0 7 95 89 1.8 2.6 0 0 IV 8 99 92 2.2 3.2 0 - 9 99 93 2.3 3.3 0 0 10 99 95 2.3 3.4 0 0 11 100 97 2.5 3z8 o 0 * IV 12 96 88 2.0 3.0 o 0 13 95 88 2.0 3.0 0 0 II 14 95 88 2.0 3.0; O 15 94 88 2.0 3.1 0 0 16 95 88 2.0 3.1 o 0 17 95 89 2.0 3.2 o 0 18 95 89 2.0 3.2 0 0 19 95 89 2.0 3.2 o - 20 95 89 2.0 3.2 o 0 II 21 95 90 2.0 3.2 o 0 22 96 90 2.0 3.2 o 0 23 96 90 2.0 3.2 o 0 24 96 90 2.0 3.3 o 0 25 96 91 2.1 3.4 ° 0 26 96 91 2.1 3.6 a * 27 96 91 2.1 3.7 x # »IV 28 96 91 2.1 3.8 x # 29 96 91 2.1 3.8 x # 30 94 90 2.0 3.3 x # V Note: 1 --- basic concept II --- preferred embodiment III --- pure Ti IV --- comparative example V --- conventional alloy The data in Table 1 clearly show that the titanium alloy according to the invention compared with the conventional alloy ( Sample No. 30) and comparative examples containing Cu or Al (Samples 6, 11, 25 to 29) in excess, is much richer in workability including deformability due to their large elongation and low tensile strength. It is harder than pure Ti, as shown in Table 1, and as shown in Table 2, has by far tougher elasticity than pure Ti.

Completely different from the comparative examples, which in excess Containing Cu and Al, it does not crack when pressed. Table 2 illustrates also that the titanium alloy according to the invention is significantly better in spot weldability especially when compared with the conventional alloy.

As a result, the titanium alloy according to the invention is special suitable for use in the manufacture of fashion items such as watches and glasses frames.

Claims (3)

Claims 7 £ - Titanium alloy for decorative use, d a it is indicated that they are 0.05% to 4X of the weight Ni, 0.05% up to 4% by weight of Cu, 1% or less by weight of total impurities, and the remaining amount essentially contains Ti. 2. Titanium alloy according to claim 1, d a d u r c h g e k e n n z e i n e t that it further contains 0.01X to 1.0% by weight of Al. 3. Titanium alloy according to claim 1 or 2, d a d u r c h g e k e n It is noted that the impurities contain 0, N, H, Fe and Co.