DE2010870A1 - Cast zinc alloy - Google Patents

Description

Dr.mont. Dipl.-Ing. Erich Pelzel Frankfurt / M., March 6, 1970 5190 Stolberg / Rhineland DrQ / GKp

Otto-Lilienthal-Strasse 3

Prov. No. 6461 PZ

Cast zinc alloy

The invention relates to a titanium-containing cast zinc alloy.

Unalloyed zinc is suitable as a cast product due to the low values of its mechanical properties only for Art cast and is therefore hardly used in other areas of application. The main alloying partners of zinc casting alloys are aluminum and copper. Through this compo- ^ nents, the pourability and the fluidity of the melt are improved, and grain refinement is achieved the mechanical and technological properties, especially with regard to hardness, strength and impact resistance elevated. In addition, the aluminum content reduces the absorption of self by the alloy melt. Refined copper in a similar way to the aluminum the structure formation and brings a substantial hardening of the alloy with it. Even small amounts of magnesium increase the strength and compensate for the influence of the accompanying metals tin and lead and cadmium, the permissible proportion of which is strictly limited.

Thus Zinkgußlegierungen are known, for example, the # 9 to 11 aluminum, 0.5 to 0.8 fi copper, 0.02 to 0.06 f <> magnesium, remainder fine zinc or 3 "5 to 5 $ aluminum, 2.4 to 4 $> Copper possibly contains up to 0.06 # magnesium, the remainder fine zinc (zinc advice center Berlin: Zinktaschenbuch, Halle 1941, pages 95/99).

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However, alloys of such a composition have the disadvantage of creep, which, starting at room temperature, is a time-dependent deformation under constant load. The reason for this is the low crystal recovery temperature due to the low melting point. The stress at which the creep just comes to a standstill at a certain temperature, i.e. the stress that the alloy can withstand for an indefinite period of time without breaking, is called the creep strength. For a permanent low deformation of $ 1> per year, the creep strength value for such alloys is only 3

up to 5 kp / mm.

Only recently has it been possible to use titanium-containing Zinc-copper alloys of the composition

0.5 to 1.2 # copper 0.1 to 0.2 $> titanium
The rest of the zinc

to increase the values for the creep strength significantly, ie to 8 to 11 kp / mm ² (Neufert, E .: STZ-Metall im Bauwesen, Berlin-Frankfurt-Wien 1963, pages 39/40; Paschen, P .: Erzmetall, J2, (1964), 7, pages 362/65). This effect is achieved by a titanium additive which shifts the annealing stability of the cured by the copper alloy at 300 ⁰ C. The hardness of these alloys, which is approximately HB 40 to 65 kp / mm at room temperature, can be increased up to 80 kp / mm with increasing copper content up to 4 #. The disadvantage of these alloys, which makes them unsuitable for many uses, their 25 kg to 50 / mm falling hot hardness in temperature ranges from 30 to 200 ⁰ C, in particular from 60 to 150 ⁰ C. Therefore, could these alloys as cast alloys, for example, Mold and machine parts that heat up during operation are not used.

The invention has now set itself the task of this after-

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eliminate parts and develop a cast zinc alloy, whose hot hardness and fatigue strength are significantly higher than that of known cast zinc alloys.

According to the invention, this object is achieved by a titanium-containing one Cast zinc alloy of the composition

$ 0.05 to $ 1>

preferably 0.1-0.59 & titanium

$ 0.1 to $ 7.5>

preferably 0.8 to 7.5 #

especially 3 to 6 # hangan

Hest Peinzink
solved. -

According to a further feature of the invention, the alloy can be 0.01 to 1.4, preferably 0.01 to 0.8 # aluminum for Purpose of uniform structure formation during solidification contain.

To prevent intergranular corrosion, up to 0.08 % of magnesium can optionally be added to the alloy. ■ ".-."■;;; : - ^;: ; 'Ä ^ _; '"· Λ

There is also the possibility * up to: ^ u 10 $> to replace the manganese content with copper * ν ^v "'

Without the good mechanical properties of the invention are negative Iiegierung beeinfiuöt, the titanium content can be partially dturch Chrome be replaced, but the chromium content of the alloy should not exceed 0.2 i ».

The invention is illustrated below with the aid of several exemplary embodiments explained in more detail. That the first embodiment example- ■ game refers to a prior art titanium-containing zinc-copper cast alloy, while the execution

109840/0669 - 4 -

tion examples 2 and 5 the cast zinc alloy according to the invention affect.

Example 1

Zinc cast alloy of the composition:

1.2 io copper

$ 0.2> titanium

Remainder fine zinc 99.99

The mechanical properties are:

Endurance strength at 1 $ elongation / year 9 kp / mm

Tensile strength 25 kp / mm ²

Brinell hardness at 20 ^° C. 60 kp / mm

Brinell hardness at 15O ⁰ C 35 kgf / mm ²

Embodiment 2 Zinc cast alloy of the composition:

1.80 i » manganese

0.15 i> titanium

Remainder fine zinc 99.99 The mechanical properties are: Endurance strength at 1 $> elongation / year 12 kp / mm Tensile strength 25 kp / mm Brinell hardness at 2O ⁰ C 80 kp / mm ² Brinell hardness at 15O ⁰ C 60 kgf / mm ² Embodiment 3 Zinc cast alloy of the composition:

4.5 # manganese 0.4 ί titanium 0.1 i> aluminum

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The mechanical properties are:

Endurance strength at 1 $ elongation / drive 12 kp / mm

Tensile strength 25 kp / mm ²

Brinell hardness at 20 ⁰ C 155 kp / mm ²

Brinell hardness at 15O ⁰ C 110 kgf / mm ²

If the mechanical properties of the alloys shown in the above embodiments are related to one another, it is shown that the alloy composition according to the invention not only increases the fatigue strength, which is not insignificant in practice, but also in particular a considerable increase in hot hardness compared to that mentioned in the first embodiment titanium-containing zinc-copper cast alloy can be achieved. The improved mechanical properties in particular permit the use of the invention for Zinkgußlegierung form and machine parts, preferably at temperatures of 30 to 200 ⁰ C 60 to 150 ⁰ C on pressure and / or friction are claimed.

_ 6 patent claims

1 0 9 8 4 0/0 6 G 9

Claims (6)

PATENT CLAIMS 1) Titanium-containing cast zinc alloy, characterized by its composition 0.05 to 1 #, preferably 0.10 to 0.5 ^ titanium £ 0.10 to £ 7.5 preferably # 0.80 to 7.5 especially 3 to 6 # manganese Remainder Peinzink 99.99 2) Titanium-containing cast zinc alloy according to claim 1, characterized by an aluminum content of 0.01 to 1.4 i » preferably 0.01 to 0.8 ^. 3) Titanium-containing zinc casting alloy according to claims 1 and 2, characterized by a magnesium content of up to 0.08 °, 4) Titanium-containing cast zinc alloy according to claims 1 to 3 » characterized in that up to 10 $> of the manganese content are replaced by copper. 5) Titanium-containing zinc casting alloy according to claims 1 to 4, characterized in that the titanium is partially replaced by chromium, but the chromium content of the alloy should be at most 0.02 » . 6) use are claimed a Zinkgußlegierung according to claims 1 to 5 for molded and machine parts, which at temperatures of 30 to 200 ⁰ C predominantly 60 to 150 ⁰ C on pressure and / or friction. 109840/0869