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EP 3 649 266 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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27.01.2021 Bulletin 2021/04 |
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Date of filing: 02.07.2018 |
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International Patent Classification (IPC):
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International application number: |
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PCT/EP2018/067808 |
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International publication number: |
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WO 2019/007906 (10.01.2019 Gazette 2019/02) |
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TITANIUM-CONTAINING ZINC WROUGHT ALLOY
TITANHALTIGE ZINK-KNETLEGIERUNG
ALLIAGE DE ZINC CORROYÉ CONTENANT DU TITANE
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Designated Contracting States: |
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AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL
NO PL PT RO RS SE SI SK SM TR |
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Priority: |
04.07.2017 EP 17179643
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Date of publication of application: |
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13.05.2020 Bulletin 2020/20 |
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Proprietor: Grillo-Werke AG |
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47169 Duisburg (DE) |
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Inventors: |
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- HÜTTIG, Jan
47169 Duisburg (DE)
- MELZER, Armin
47169 Duisburg (DE)
- PRENGER, Frank
47169 Duisburg (DE)
- ROLLEZ, Didier
47169 Duisburg (DE)
- VAN WESEL, Markus
47169 Duisburg (DE)
- VON KRIES, Joanna
47169 Duisburg (DE)
- WISNIEWSKI, Jürgen
47169 Duisburg (DE)
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Representative: dompatent von Kreisler Selting Werner -
Partnerschaft von Patent- und Rechtsanwälten mbB |
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Deichmannhaus am Dom
Bahnhofsvorplatz 1 50667 Köln 50667 Köln (DE) |
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References cited: :
EP-A1- 2 385 148
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FR-A5- 2 102 861
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] The present invention relates to a zinc wrought alloy with improved machinability
as compared to known wrought alloys, as well as semifinished products, forgings, turned
parts, locks, screw connections, locking cylinders, sleeves, fittings, pressed parts,
pneumatic parts, hydraulic parts, mountings, valves and ball valves that comprise
a zinc wrought alloy according to the invention.
[0002] A wide variety of copper-zinc alloys (brass alloys) are known in the prior art. When
objects are prepared from these alloys, they are processed with shaping, for example,
by machining. Thus, machinability, i.e., the property of a material to be processable
by machining, is an important characteristic of corresponding materials. To improve
their machinability, brass alloys are often alloyed with lead, such as free-machining
brass, CuZn39Pb3.
[0003] In recent years, the conditions to be met for the protection of health and environment
have been tightened up significantly by the legislation in many fields. This affects,
in particular, a ban or a drastic reduction of lead as an alloy component in copper
alloys (see, for example, [1] Verordnung zur Novellierung der Trinkwasserverordnung
vom 21. Mai 2001, German Federal Law Gazette, Issue 2001, Part I No. 24, issued in
Bonn on May 28, 2001; [2] Directive 2000/53/EC of the European Parliament and of the
Council of September 18, 2000, on end-of-life vehicles, Official Journal of the European
Communities, L 269/34, DE, October 21, 2000; or [3] Directive 2002/95/EC of the European
Parliament and of the Council of January 27, 2003, on the restriction of the use of
certain hazardous substances in electrical and electronic equipment, Official Journal
of the European Union, February 13, 2003, DE, L 37/19). Therefore, in view of these
conditions to be met, low-lead brass alloys were developed, but which can still contain
up to 0.25% lead. In addition to brass alloys, zinc alloys have also been described
in the prior art. Herein, low lead or even lead-free alloys are increasingly being
developed. As an example,
EP 2675971 A - "Accessory consisting of a lock accessory" may be mentioned. It discloses a zinc
alloy with an Al content of from 13 to 25%, a Cu content of from 0.2 to 3.5%, and
an Mg content of less than 0.1%, which is employed for lock accessories.
[0004] EP 2 385 148 A - "Zinc alloy with high creep resistance" relates to a zinc-aluminum alloy with an
Al content of 10 to < 25%, a Cu content of 0.05 to 3%, an Mg content of from 0.001
to 0.1%, an Mn content of 0.05% to 1.0% and an Si content of from 0.05 to 1%. The
disclosed alloy has a high creeping resistance and is suitable for the furnace brazing
and normal brazing of heat exchangers.
[0005] US 3,734,785 - "Zinc forging alloy" claims a zinc-based alloy with an Al content of 9 to 22%,
a Cu content of 0.5 to 1.5%, and an Mg content of 0.01 to 0.03%, which is particularly
suitable for hot formability.
[0006] US 3,880,679 - "Method of forming zinc-aluminum alloys with good machinability" describes zinc-aluminum
alloys with an Al content of 22 to 27%, a Cu content of 0 to 10%, an Mg content of
0.01 to 1%, and a Bi content of 0.01 to 3%.
[0007] EP 0 679 198 A - "Method for producing Zn-Al-Cu alloy articles by centrifugal or die casting" describes
a zinc alloy with an Al content of 6.0 to 8.0%, a Cu content of 3.2 to 4.3%, for preparing
articles by centrifugal casting in a rubber mold, or pressure die-casting in a metal
mold.
[0008] Also widely known are zinc pressure die-casting alloys, also referred to as ZAMAK®.
These consist of zinc-aluminum-copper-magnesium alloys, which cannot have the corresponding
strength properties, however. Further, machining is clearly more problematic in zinc
pressure die-casting alloys because of the higher porosity structure.
[0009] Proceeding from this prior art, it has been the object of the present invention to
provide a zinc-based wrought alloy having an improved machinability as compared to
the prior art. At the same time, the mechanical properties should not be adversely
affected. The improved machinability is to be achieved without including lead in the
alloy. Surprisingly, it has been found that titanium enables an improved machinability
of zinc wrought alloys. "Alloying" basically means the preparation of an alloy by
melting a metal together with at least one other metal or non-metal. If in the present
application it is referred to the fact that a metal or non-metal is not alloyed to
an alloy, this means that the metal or non-metal in question is not actively added.
[0010] Therefore, in a first embodiment, the object of the present invention is achieved
by a zinc wrought alloy having an Al content of from 5% by weight to 18% by weight,
a Cu content of from 0.1% by weight to 4% by weight, an Mg content of from 0.001%
by weight to 0.05% by weight, a Ti content of from 0.01% by weight to 1% by weight,
wherein Zn is the balance to 100%, and wherein the alloy may contain impurities at
a proportion of 0.07% by weight or less.
[0011] This is by purposefully alloying with titanium in zinc-aluminum-copper-magnesium
alloys, which may then be used in the preparation of a wide variety of semifinished
products and articles, such as forgings, turned parts, locks, screw connections, locking
cylinders, sleeves, fittings, pressed parts, pneumatic parts, hydraulic parts, mountings,
valves or ball valves. Titanium is an extremely effective alloy element, strongly
affecting the microstructure already in the ppm range because of its lattice structure.
With it, a better machinability can be achieved. At the same time, the mechanical
properties of the alloy are not adversely affected. Further, the zinc alloy according
to the invention has very good hot formability properties.
[0012] If percentages are stated with respect to components contained in the alloy in the
present application, they are percent by weight unless explicitly stated otherwise,
respectively based on the total weight of the alloy. In particular, no further metals
in addition to the metals mentioned are alloyed with the alloy when it is prepared.
More preferably, the alloy according to the invention is free of zirconium. Surprisingly,
it has been found that an improved machinability, in particular, is achieved by selectively
alloying titanium. Other zinc wrought alloys (as disclosed, for example, in
EP 2675971 - "Accessory consisting of a lock accessory") have a poorer machinability (chip formation).
Surprisingly, the machining index could be brought into the reference range of free-machining
brass (CuZn39Pb3) by alloying with titanium, but without having to alloy with lead.
In addition, very good drilling, milling and broaching properties are obtained. Further,
processing may be dry or wet. Alloying with lead is not necessary. Preferably, lead
is not alloyed. Preferred is a Pb content in the alloy according to the invention
of ≤0.003% by weight, especially < 0.003% by weight, which is present in the alloy
as an impurity of zinc, in particular, but not as an additional alloy component.
[0013] In addition, surprisingly, the microstructure (fineness of grain) can be influenced
by alloying with titanium so that the forgeability is significantly improved. The
proportion of titanium (Ti) in the alloy according to the invention is preferably
from 0.01% to 1% by weight, especially from 0.03% to 1% by weight, specifically from
0.05% to 1% by weight, preferably from 0.06% to 1% by weight. It has been found that
these proportions of titanium are sufficient to achieve the improved properties. Larger
amounts are not necessary and also can be introduced only with difficulty without
adversely affecting the microstructure of the alloy. Particularly preferred is a Ti
content of from 0.05% to 1% by weight.
[0014] In addition to the mentioned components (Zn, Al, Cu, Mg, Ti), the alloy according
to the invention may also comprise impurities resulting from the fact that these components
(Zn, Al, Cu, Mg, Ti) are derived from recycling. However, for the usual sources of
the components (Zn, Al, Cu, Mg, Ti), these are not critical. Common impurities are
Cd, Pb, Sn and/or Fe. Preferably, these impurities are contained only in very small
amounts, so that they do not affect the properties of the alloy according to the invention.
Therefore, preferred is a Pb content of < 0.003% by weight, and/or a Cd content of
< 0.003% by weight, especially < 0.0005% by weight, and/or an Sn content of < 0.001%
by weight, especially of < 0.0005% by weight, and/or an Fe content of < 0.05% by weight.
Preferably, the content of all stated impurities is below the mentioned values. Preferably,
the content of all impurities is 0.07% by weight or less.
[0015] The alloys according to the invention are suitable for surface treatments (for example,
electroplating, PVD, CVD, passivation, painting, cathodic dip painting/coating, powder
coating).
[0016] Particularly preferred is a zinc wrought alloy with a content of aluminum (Al) of
from 5 % by weight to 18 % by weight, especially from 8% to 18% by weight, preferably
from 10% to 16% by weight, more preferably from 5 % to 9% by weight, preferably from
10% to 12% by weight, more preferably from 14% to 16% by weight, especially from 16%
to 18% by weight. These ranges are preferred because all alloys are supereutectic
therein, and there is a first beta phase in the crystal structure. This beta phase
is preferred because it recrystallizes at room temperature very slowly (> 10 years),
so that the properties of the alloy are retained.
[0017] Particularly preferred is a zinc wrought alloy with a content of copper (Cu) of from
0.1% to 2.5% by weight, especially from 0.5 to 1.5% by weight. This range is preferred
to achieve the maximum mechanical strength, and to avoid the risk of forming of a
brittle epsilon phase in the crystal structure.
[0018] Particularly preferred is a zinc wrought alloy with a content of magnesium (Mg) of
from 0.003 % by weight to 0.05 % by weight, especially from 0.003% to 0.03% by weight.
This range serves as a precaution to prevent intercrystalline corrosion by the residual
traces of impurities.
[0019] The titanium content of at most 1% in the zinc alloy is limited by the solubility
of titanium.
[0020] The zinc wrought alloy according to the invention may further contain silicon as
an impurity. If it contains silicon, the content of silicon in the alloy is within
a range of from 0.005% by weight to 0.02% by weight, in particular. The silicon content
is determined by the selection of Al, because silicon is an impurity in aluminum.
[0021] It has been found that an alloy having an Al content of from 10% to 12% by weight,
a Cu content of from 0.5% by weight to 1.5% by weight, an Mg content of from 0.003%
by weight to 0.05% by weight, a Ti content of from 0.05% to 1% by weight, with zinc
as the balance to reach 100% by weight, has particularly good properties with respect
to machinability. At the same time, mechanical properties, such as strength or hardness,
are not adversely affected. Therefore, such an alloy is preferred.
[0022] Particularly preferred according to the invention is a zinc wrought alloy with an
Al content of from 14% to 16% by weight, a Cu content of from 0.5% by weight to 1.5%
by weight, an Mg content of from 0.003% by weight to 0.05% by weight, a Ti content
of from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight. Corresponding
alloys have good properties with respect to machinability and in addition have a good
processability. Herein, mechanical properties of the alloy, such as strength or hardness,
are not adversely affected.
[0023] Further preferred alloys have the following compositions:
- aluminum content of from 5% to 9% by weight, copper content of from 0.5% to 2.5% by
weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of from
0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 5% to 9% by weight, copper content of from 0.5% to 1.5% by
weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of from
0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 10% to 12% by weight, copper content of from 0.5% to 2.5%
by weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 10% to 12% by weight, copper content of from 0.5% to 1.5%
by weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 14% to 16% by weight, copper content of from 0.5% to 2.5%
by weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 14% to 16% by weight, copper content of from 0.5% to 1.5%
by weight, magnesium content of from 0.003% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 16% to 18% by weight, copper content of from 0.5% to 2.5%
by weight, magnesium content of from 0.001% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight;
- aluminum content of from 16% to 18% by weight, copper content of from 0.5% to 1.5%
by weight, magnesium content of from 0.001% to 0.05% by weight, titanium content of
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight.
[0024] The present invention further relates to the use of the titanium-containing zinc
wrought alloy according to the invention for preparing semifinished products and articles
with improved machining properties. Further included according to the invention is
a semifinished product or article obtainable by processing the zinc wrought alloy
according to the invention. This semifinished product may be, in particular, a billet,
an extruded section, a drawn section, a wire, a strip, a powder, or a pressure die-cast
alloy. In particular, the article may be a forging, turned part, lock, screw connection,
locking cylinder, sleeve, fitting, pressed part, pneumatic part, hydraulic part, mounting,
valve or ball valve.
[0025] The semifinished product according to the invention, especially the billet, can be
prepared, for example, by casting the zinc wrought alloy according to the invention
into a mold. When the alloy according to the invention has been formed into a billet
shape, for example, a section can be prepared therefrom by reshaping by means of extrusion.
Further, the zinc wrought alloy according to the invention can be processed by different
reshaping methods. Such reshaping methods include, in particular, rolling, forging,
drawing. The articles according to the invention are excellently suitable for being
subjected to machining methods.
[0026] The zinc wrought alloy according to the invention and the articles prepared therefrom
exhibit an improved machinability as compared to conventional ZnAI/ZnAICu/ZnAICuMg
alloys.
[0027] The requirement for the invention is to enhance the processability of zinc wrought
alloys. This object was achieved by alloying with titanium. There may be mentioned,
in particular, the machining properties that were significantly improved thereby,
so that a machining index within the reference range of free-machining brass (CuZn39Pb3)
can be achieved. In the experiments, it is found that the titanium content leads to
ideal chip shapes. Surprisingly, increased cutting speeds could be achieved additionally,
which significantly enhances productivity.
[0028] The prepared products made of the titanium-containing zinc wrought alloy according
to the invention are more cost-effective than comparably lead-free brass materials.
This results from a lower density and an excellent processability caused by the optimum
composition of zinc, aluminum, copper, magnesium and titanium.
[0029] In the following Examples, the present invention is further explained in a nonlimiting
way, and advantages over the prior art are pointed out.
Examples
[0030] The zinc wrought alloy according to the invention was compared with the following
materials:
Table 1: Comparative material (comparative experiments)
Properties |
Unit |
Zinc alloy |
Aluminum content |
% by weight |
13-25 |
Copper content |
% by weight |
0.2-3.5 |
Magnesium content |
% by weight |
< 0.1 |
Lead content |
% by weight |
< 0.004 |
Zinc content |
% by weight |
balance |
Tensile strength |
MPa |
412 |
Yield strength |
MPa |
374 |
Brinell hardness |
HB (2.5/62.5) |
128 |
Creep tendency (AfRT100.1) |
% |
0.05 |
[0031] A zinc wrought alloy as described in
EP 2 675 971 was used as a comparative material (information in column "zinc alloy" in Table 1).
[0032] The qualification of the zinc wrought alloy according to the invention is based on
four methods delimited from one another, which are set forth in the following. They
are the basis of the determination of the claimed composition boundaries. If one of
the compositions showed defects, this led to exclusion.
[0033] From a zinc alloy as described in Table 1 as well as from the following alloys according
to the invention, billets having a diameter of 135 mm were prepared, which served
as a starting point for the qualification:
Table 2: Alloys according to the invention
Components |
Unit |
Specimen 1 |
Specimen 2 |
Specimen 3 |
Specimen 4 |
Aluminum |
% by weight |
5 -9 |
10-12 |
14-16 |
16-18 |
Copper |
% by weight |
0.5-2.5 |
0.5-1.5 |
0.5-1.5 |
0.5-2.5 |
Magnesium |
% by weight |
0.003-0.05 |
0.003-0.05 |
0.003-0.05 |
0.003-0.05 |
Titanium |
% by weight |
0.05-1 |
0.05-1 |
0.05-1 |
0.05-1 |
[0034] Both the billets/alloys according to the invention and the comparative alloys/billets
were analyzed by the following methods relating to different mechanical properties
as well as machinability (qualification):
Method 1 (reshaping method):
[0035] The billet was heated at 250 °C in an oven. Thereafter, the billet was extruded into
a round section. Further, the extruded round rod was drawn to a final dimension of
26 mm. The testing requirements were considered to be met if no signs of surface cracks
or blisters have formed.
Method 2 (tensile test):
[0036] As the second method, a tensile test was performed. The exact realization, the definition
of the measurable characteristics and the specimen shape are defined in DIN EN ISO
6892-1:2017.
[0037] A section of the drawn round rod having a diameter of 26 mm was lathe-turned into
a specimen for tensile testing as shown in Figure 1. It was clamped into the tensile
testing machine and exposed to a uniaxial load until the specimen broke. Meanwhile,
the force, width and length were continuously measured electronically, whereby the
stress-strain curve (Figure 2) could be determined.
Method 3 (creep tendency):
[0038] Further, the creep tendency or creep strength according to DIN EN ISO 204:2009 was
tested as a third method. A specimen as shown in Figure 1 was subjected to a long-acting
uniaxial tensile force at a constant test temperature. In this case, the specimen
was loaded constantly with 100 MPa at room temperature. Meanwhile, the axial strain
was measured.
Method 4 (shape of chip):
[0039] In the fourth method, a section of the drawn round rod was clamped into a turning
machine. A turned part having rotational symmetry with five recessed grooves having
widths of 3 mm and depths of 3 mm was prepared therefrom. The testing requirements
were considered to be met if the chip shape corresponds to industrial custom.
Results:
[0040] At first, the different alloy ranges were tested with respect to aluminum content,
because the latter represents the major alloy component. In the following Table 3,
the mechanical characteristics of the alloys according to the invention (samples 1
to 4 according to Table 2) are shown. They were determined by the above described
methods 2 and 3.
Table 3: Mechanical characteristics of the alloys according to the invention (methods
2 and 3)
Properties |
Unit |
Specimen 1 |
Specimen 2 |
Specimen 3 |
Specimen 4 |
Tensile strength |
MPa |
397 |
392 |
411 |
422 |
Yield strength (Rp0.2) |
MPa |
322 |
347 |
372 |
381 |
Brinell hardness |
HB (2.5/62.5) |
136 |
128 |
132 |
133 |
Creep tendency (AfRT100.1) |
% |
0.01 |
0.04 |
0.05 |
0.05 |
[0041] Surprisingly, the selective alloying with titanium did not have a negative impact
on the mechanical characteristics. In the comparison with the comparative material
(zinc alloy from Table 1), no significant differences could be seen.
Results of method 4 (shapes of chips) - specimens 1, 2, 3 and 4:
a) Specimens 1 to 4 according to the invention were processed as described above under
method 4 with the following parameters:
[0042]
Table 4: Machining parameters (high cutting speed)
Cutting speed [m/min] |
Feed speed [mm/U] |
210 |
0.05 |
[0043] Photographs of the chip shapes and the specimens that were processed are shown in
Figure 3. From the results, it can be readily seen that all ranges of the present
invention showed a good machinability. This was shown by the spiral chips produced
by each of the four specimens. Spiral chips are advantageous, in particular, for automated
production processes. The high cutting speed achieved increases efficiency and is
thus also very advantageous.
b) Specimens 1 to 4 according to the invention were processed as described above under
method 4 with the following parameters:
[0044]
Table 5: Machining parameters (medium cutting speed)
Cutting speed [m/min] |
Feed speed [mm/U] |
90 |
0.15 |
[0045] Photographs of the chip shapes and the specimens that were processed are shown in
Figure 4. At a medium cutting speed, all the specimens showed a good machinability.
Both spiral chips and conical helical chips were produced.
Other alloys according to the invention - specimens 3a to 3d
[0046] Further, different titanium contents were tested for determining a preferred composition
by means of specimen 3:
Table 6: Specimens with different titanium contents (alloy according to the invention):
Components |
Unit |
Specimen 3a |
Specimen 3 |
Specimen 3b |
Specimen 3c |
Specimen 3d |
Aluminum |
% by weight |
14-16 |
14-16 |
14-16 |
14-16 |
14-16 |
Copper |
% by weight |
0.5-1.5 |
0.5-1.5 |
0.5-1.5 |
0.5-1.5 |
0.5-1.5 |
Magnesium |
% by weight |
0.003-0.05 |
0.003-0.05 |
0.003-0.05 |
0.003-0.05 |
0.003-0.05 |
Titanium |
% by weight |
0.01-0.05 |
0.06-0.1 |
0.15-0.2 |
0.25-0.4 |
0.8-1.0 |
Results of methods 2 and 3 - specimens 3a, 3b and 3c:
[0047] The following Table 7 shows the results of the mechanical properties of the specimens
(results of methods 2 and 3).
Table 7: Mechanical properties of the specimens with different titanium contents (methods
2 and 3)
Properties |
Unit |
Specimen 3a |
Specimen 3 |
Specimen 3b |
Specimen 3c |
Tensile strength |
MPa |
401 |
411 |
409 |
410 |
Yield strength (Rp0.2) |
MPa |
365 |
372 |
370 |
369 |
Brinell hardness |
HB (2.5/62.5) |
129 |
132 |
133 |
131 |
Creep tendency (AfRT100.1) |
% |
0.03 |
0.05 |
0.04 |
0.04 |
[0048] Surprisingly, the titanium content in different amounts does not show any negative
impact on the mechanical properties.
Results of method 4 (shapes of chips) - specimens 3a, 3b, 3c and 3d:
[0049] The machining parameters of Tables 4 and 5 remained identical. Photographs of the
chip shapes and the specimens that were processed are shown in Figures 5 (parameters
according to Table 4) and 6 (parameters according to Table 5).
[0050] In the comparison in Figure 5, it can be readily seen that the machining properties
were improved as the titanium content increased. The chips achieved good chip shapes,
which clearly enhances productivity in the processing in a turning machine. These
include, but are not limited to, short helical chips, spiral chips, and long helical
chips. Further, it was found that the alloy having a Ti content of 0.1% by weight
is particularly process-safe. It constantly produced long helical chips, while the
chip length varied more with the other titanium contents.
[0051] The results from Figure 6 are similar to those of Figure 5 and also show good machining
properties. Short helical chips were produced in most cases.
[0052] In the last step, the alloy 3 according to the invention was compared with the comparative
material from
EP 2 657 971.
Results of method 4 (shapes of chips) - specimen 3 vs. zinc alloy according to EP 2 675 971:
[0053] The machining parameters of Tables 4 and 5 remained identical. Photographs of the
chip shapes and the specimen that was processed are shown in Figures 7 (parameters
according to Table 4) and 8 (parameters according to Table 5).
[0054] In the comparison in Figure 7, the extent of improvement of the chip shapes by the
zinc alloy according to the invention can be readily seen. At a cutting speed of 210
m/min, long entangled chips were produced with the zinc alloy from the prior art (as
mentioned in
EP 2 675 971, Comparative Example). Surprisingly, a clearly better chip shape could be achieved
by selectively alloying with titanium. Such chip shape of the inventive alloys are
ideal for processing in a turning machine, avoiding risks and disruptions in the cutting
process, such as the chip becoming wound up around the workpiece or the tool. A high
cutting speed is also desirable, and is also possible with the alloy according to
the invention, because the process speed of the semifinished products in the turning
machine can be increased. Surprisingly, the high cutting speed can be achieved by
the present invention.
[0055] Also at lower cutting speeds, as shown in Figure 8, the zinc alloy according to the
invention achieved chip shapes that are better for turning processing as compared
to those obtained with the comparative zinc alloy as described in
EP 2 675 971.
1. A zinc wrought alloy having an Al content of from 5% by weight to 18% by weight, a
Cu content of from 0.1% by weight to 4% by weight, an Mg content of from 0.001% by
weight to 0.05% by weight, a Ti content of from 0.01% by weight to 1% by weight, wherein
Zn is the balance to 100%, and wherein the alloy may contain impurities at a proportion
of 0.07% by weight or less.
2. The zinc wrought alloy according to claim 1, characterized in that lead is not alloyed.
3. The zinc wrought alloy according to claim 1 or 2, characterized in that the content of Al is from 8% to 16% by weight, preferably from 10% to 14% by weight,
preferably from 10% to 12% by weight, or from 14% to 16% by weight.
4. The zinc wrought alloy according to any of claims 1 to 3, characterized in that the content of Ti is from 0.03% to 1% by weight, preferably from 0.05% to 1% by weight,
especially from 0.06% to 1% by weight.
5. The zinc wrought alloy according to any of claims 1 to 4, characterized in that the content of Cu is from 0.1% to 2.5% by weight, especially from 0.5% to 1.5% by
weight.
6. The zinc wrought alloy according to any of claims 1 to 5, characterized in that the content of Mg is from 0.003 % by weight to 0.05% by weight, especially from 0.003%
by weight to 0.03% by weight.
7. The zinc wrought alloy according to any of claims 1 to 6, characterized by containing silicon as an impurity, especially with a content from 0.005% to 0.02%
by weight.
8. The zinc wrought alloy according to any of claims 1 to 7, having an Al content from
5% to 9% by weight, a Cu content from 0.5% to 2.5% by weight or from 0.5% to 1.5%
by weight, a magnesium content from 0.003% to 0.05% by weight, a titanium content
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight.
9. The zinc wrought alloy according to any of claims 1 to 7, having an Al content from
10% to 12% by weight, a Cu content from 0.5% to 2.5% by weight or from 0.5% to 1.5%
by weight, an Mg content from 0.003% to 0.05% by weight, a Ti content from 0.05% to
1% by weight, with zinc as the balance to reach 100% by weight.
10. The zinc wrought alloy according to any of claims 1 to 7, having an Al content from
14% to 16% by weight, a Cu content from 0.5% to 2.5% by weight or from 0.5% to 1.5%
by weight, an Mg content from 0.003% to 0.05% by weight, a Ti content from 0.05% to
1% by weight, with zinc as the balance to reach 100% by weight.
11. The zinc wrought alloy according to any of claims 1 to 7, having an Al content from
16% to 18% by weight, a Cu content from 0.5% to 2.5% by weight or from 0.5% to 1.5%
by weight, a magnesium content from 0.001% to 0.05% by weight, a titanium content
from 0.05% to 1% by weight, with zinc as the balance to reach 100% by weight.
12. Use of the zinc wrought alloy according to any of claims 1 to 11 for preparing semifinished
products and/or articles.
13. The use according to claim 12, wherein said semifinished product is a billet, an extruded
section, a drawn section, a wire, a strip, a powder, or a pressure die-cast alloy;
and/or
wherein said article is a forging, turned part, lock, screw connection, locking cylinder,
sleeve, fitting, pressed part, pneumatic part, hydraulic part, mounting, valve or
ball valve.
14. Semifinished products, forgings, turned parts, locks, screw connections, locking cylinders,
sleeves, fittings, pressed parts, pneumatic parts, hydraulic parts, mountings, valves
and ball valves, characterized by comprising, especially consisting of, a zinc wrought alloy according to any of claims
1 to 11.
15. A process for preparing and/or reshaping and/or processing semifinished products,
forgings, turned parts, locks, screw connections, locking cylinders, sleeves, fittings,
pressed parts, pneumatic parts, hydraulic parts, mountings, valves and ball valves
according to claim 14 by cold or hot reshaping.
1. Zink-Knetlegierung mit einem AI-Gehalt von 5 Gew.-% bis 18 Gew.-%, einem Cu-Gehalt
von 0,1 Gew.-% bis 4 Gew.-%, einem Mg-Gehalt von 0,001 Gew.-% bis 0,05 Gew.-%, einem
Ti-Gehalt von 0,01 Gew.-% bis 1 Gew.-% und mit Zn auf 100 Gew.-% ausgeglichen, wobei
die Legierung gegebenenfalls Verunreinigungen in einem Anteil von 0,07 Gew.-% oder
weniger aufweist.
2. Zink-Knetlegierung nach Anspruch 1, dadurch gekennzeichnet, dass kein Blei legiert ist.
3. Zink-Knetlegierung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Gehalt an AI von 8 Gew.-% bis 16 Gew.-%, bevorzugt von 10 Gew.-% bis 14 Gew.-%,
bevorzugt von 10 Gew.-% bis 12 Gew.-% oder von 14 Gew.-% bis 16 Gew.-% beträgt.
4. Zink-Knetlegierung nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass der Gehalt an Ti von 0,03 Gew.-% bis 1 Gew.-%, bevorzugt von 0,05 Gew.-% bis 1 Gew.-%,
insbesondere von 0,06 Gew.-% bis 1 Gew.-% beträgt.
5. Zink-Knetlegierung nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass der Gehalt an Cu von 0,1 Gew.-% bis 2,5 Gew.-%, insbesondere von 0,5 bis 1,5 Gew.-%
beträgt.
6. Zink-Knetlegierung nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass der Gehalt an Mg 0,003 Gew.-% bis 0,05 Gew.-%, insbesondere 0,003 Gew.-% bis 0,03
Gew.-%, beträgt.
7. Zink-Knetlegierung nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass sie Silicium als Verunreinigung aufweist, insbesondere mit einem Gehalt von 0,005
Gew-% bis 0,02 Gew-%.
8. Zink-Knetlegierung nach einem der Ansprüche 1 bis 7, mit einem AI-Gehalt von 5 Gew.-%
bis 9 Gew.-%, einem Cu-Gehalt von 0,5 Gew.-% bis 2,5 Gew.-% oder von 0,5 Gew.-% bis
1,5 Gew.-%, einem Magnesiumgehalt von 0,003 Gew.-% bis 0,05 Gew.-%, einem Titangehalt
von 0,05 Gew.-% bis 1 Gew.-% und mit Zink auf 100 Gew.-% ausgeglichen.
9. Zink-Knetlegierung nach einem der Ansprüche 1 bis 7 mit einem AI-Gehalt von 10 Gew.-%
bis 12 Gew.-%, Cu-Gehalt von 0,5 Gew.-% bis 2,5 Gew.-% oder von 0,5 Gew.-% bis 1,5
Gew.-%, einem Mg-Gehalt von 0,003 bis 0,05 Gew.-%, einem Ti-Gehalt von 0,05 Gew.-%
bis 1 Gew.-% und mit Zink auf 100 Gew.-% ausgeglichen.
10. Zink-Knetlegierung nach einem der Ansprüche 1 bis 7 mit einem AI-Gehalt von 14 bis
16 Gew.-%, einem Cu-Gehalt von 0,5 bis 2,5 Gew.-% oder von 0,5 Gew.-% bis 1,5 Gew.-%,
einem Mg-Gehalt von 0,003 bis 0,05 Gew.-%, einem Ti-Gehalt von 0,05 bis 1 Gew.-% und
mit Zink auf 100 Gew.-% ausgeglichen.
11. Zink-Knetlegierung nach einem der Ansprüche 1 bis 7 mit einem AI-Gehalt von 16 bis
18 Gew.-%, einem Cu-Gehalt von 0,5 bis 2,5 Gew.-% oder von 0,5 bis 1,5 Gew.-%, einem
Magnesiumgehalt von 0,001 bis 0,05 Gew.-%, einem Titangehalt von 0,05 Gew.-% bis 1
Gew.-% und mit Zink auf 100 Gew.-% ausgeglichen.
12. Verwendung der Zink-Knetlegierung nach einem der Ansprüche 1 bis 11 zur Herstellung
von Halbzeugen und/oder Gegenständen.
13. Verwendung nach Anspruch 12, wobei das Halbzeug ein Bolzen, ein Strangpressprofil,
ein stranggezogenes Profil, ein Draht, ein Band, ein Pulver oder eine Druckgusslegierung
ist;
und/oder
wobei der Gegenstand ein(e) Schmiedeteil, Drehteil, Schloss, Verschraubung, Schließzylinder,
Muffe, Fitting, Pressteil, Pneumatikteil, Hydraulikteil, Beschlag, Ventil oder Kugelhahn
ist.
14. Halbzeuge, Schmiedeteile, Drehteile, Schlösser, Verschraubungen, Schließzylinder,
Muffen, Fittings, Pressteile, Pneumatikteile, Hydraulikteile, Beschläge, Ventile und
Kugelhähne, dadurch gekennzeichnet, dass sie eine Zink-Knetlegierung nach einem der Ansprüche 1 bis 11 umfassen und insbesondere
daraus bestehen.
15. Verfahren zur Herstellung und/oder Umformung und/oder Bearbeitung von Halbzeugen,
Schmiedeteilen, Drehteilen, Schlössern, Verschraubungen, Schließzylindern, Muffen,
Fittings, Pressteilen, Pneumatikteilen, Hydraulikteilen, Beschlägen, Ventilen und
Kugelhähnen nach Anspruch 14 durch Kalt- oder Warmumformung.
1. Alliage de corroyage de zinc, ayant une teneur en Al de 5 % en poids à 18 % en poids,
une teneur en Cu de 0,1 % en poids à 4 % en poids, une teneur en Mg de 0,001 % en
poids à 0,05 % en poids, une teneur en Ti de 0,01 % en poids à 1 % en poids, dans
lequel Zn est le complément jusqu'à 100 % en poids, et dans lequel ledit alliage peut
contenir des impuretés en une teneur de 0,07 % en poids ou moins.
2. Alliage de corroyage de zinc selon la revendication 1, caractérisé en ce qu'on n'ajoute pas de plomb dans l'alliage.
3. Alliage de corroyage de zinc selon la revendication 1 ou 2, caractérisé en ce que la teneur en Al est de 8 % à 16 % en poids, de préférence de 10 % à 14 % en poids,
de préférence de 10 % à 12 % en poids, ou de 14 % à 16 % en poids.
4. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 3, caractérisé en ce que la teneur en Ti est de 0,03 % à 1 % en poids, de préférence de 0,05 % à 1 % en poids,
notamment de 0,06 % à 1 % en poids.
5. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 4, caractérisé en ce que la teneur en Cu est de 0,1 % à 2,5 % en poids, notamment de 0,5 % à 1,5 % en poids.
6. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 5, caractérisé en ce que la teneur en Mg est de 0,003 % à 0,05 % en poids, notamment de 0,003 % à 0,03 % en
poids.
7. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 6, caractérisé en ce qu'il contient du silicium comme impureté, notamment avec une teneur de 0,005 % à 0,02
% en poids.
8. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 7, ayant
une teneur en Al de 5 % à 9 % en poids, une teneur en Cu de 0,5 % à 2,5 % en poids
ou de 0,5 % à 1,5 % en poids, une teneur en magnésium de 0,003 % à 0,05 % en poids,
une teneur en titane de 0,05 % à 1 % en poids, dans lequel Zn est le complément jusqu'à
100 %.
9. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 7, ayant
une teneur en Al de 10 % à 12 % en poids, une teneur en Cu de 0,5 % à 2,5 % en poids
ou de 0,5 % à 1,5 % en poids, une teneur en Mg de 0,003 % à 0,05 % en poids, une teneur
en Ti de 0,05 à 1 % en poids, dans lequel Zn est le complément jusqu'à 100 %.
10. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 7, ayant
une teneur en Al de 14 % à 16 % en poids, une teneur en Cu de 0,5 % à 2,5 % en poids
ou de 0,5 % à 1,5 % en poids, une teneur en Mg de 0,003 % à 0,05 % en poids, une teneur
en Ti de 0,05 à 1 % en poids, dans lequel Zn est le complément jusqu'à 100 %.
11. Alliage de corroyage de zinc selon l'une quelconque des revendications 1 à 7, ayant
une teneur en Al de 16 % à 18 % en poids, une teneur en Cu de 0,5 % à 2,5 % en poids
ou de 0,5 % à 1,5 % en poids, une teneur en magnésium de 0,001 % à 0,05 % en poids,
une teneur en titane de 0,05 à 1 % en poids, dans lequel Zn est le complément jusqu'à
100 %.
12. Utilisation de l'alliage de corroyage de zinc selon l'une quelconque des revendications
1 à 11 pour préparer des produits et/ou articles semi-finis.
13. Utilisation selon la revendication 12, dans lequel ledit produit semi-fini est un
boulon, un profilé extrudé, un profilé pultrudé, un fil, une bande, une poudre, ou
un alliage moulé sous pression,
et/ou
dans lequel ledit article est une pièce forgée, une pièce tournée, une fermeture,
un raccord vissé, un cylindre de fermeture, un manchon, un raccord, une pièce moulée,
une pièce pneumatique, une pièce hydraulique, une garniture, une vanne, ou une vanne
à boule.
14. Produits semi-finis, pièces forgées, pièces tournées, fermetures, raccords vissés,
cylindres de fermeture, manchons, raccords, pièces moulées, pièces pneumatiques, pièces
hydrauliques, garnitures, vannes, et vannes à boule, caractérisés en ce qu'ils comprennent, notamment consistent en, un alliage de corroyage de zinc selon l'une
quelconque des revendications 1 à 11.
15. Procédé pour préparer et/ou former et/ou traiter des produits semi-finis, pièces forgées,
pièces tournées, fermetures, raccords vissés, cylindres de fermeture, manchons, raccords,
pièces moulées, pièces pneumatiques, pièces hydrauliques, garnitures, vannes, et vannes
à boule, caractérisés en ce qu'ils comprennent, notamment consistent en, un alliage de corroyage de zinc selon la
revendication 14 par formage à froid ou à chaud.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description