DE1483229C2 - Use of AlMgSi-GuB alloy for cylinder heads - Google Patents

Description

The present invention relates to the use of AlMgSi cast alloys for cylinder heads.

As a result of the higher demands on the In the most diverse constructions in the present, the metallic materials are also becoming stronger claimed. These greater loads on the materials occur at low and high temperatures on. Changes in the composition of the alloys were therefore necessary. Some alloys, including the heat-resistant aluminum-magnesium-silicon alloys, are an exception. They will shed for decades with the same previous composition.

Attempts to improve aluminum-magnesium-silicon alloys were carried out almost three decades ago. These investigations concerned especially the improvement of the hardenability of alloys with 3% magnesium and 0.8% silicon. The magnesium silicide could be refined by adding cerium. With further additions of 0.8% Zinc and 0.8% manganese, which were alloyed together with cerium, achieved a further improvement, but it did not as noticeable as that by the addition of cerium. This alloy has not been found until recently Use.

Later extensive studies on the use of pressed aluminum-magnesium-silicon- Alloys have been carried out to make both the quasi-binary and ternary and hypoeutectic compositions useful for heat-resistant purposes. These attempts are not continued, although here too the high level inherent in aluminum-magnesium alloys

35 Number board 1 Si contents Not on Si
bound
magnesium Approximately
Solidus point
in the system
AIMe Total mg (° / o) (%) CQ 40 (0/0) 0.6
1.0
1.5 2.97
2.27
1.41 604
617
635 4th
4th
4th 0.6
1.0
1.5 3.77
3.07
2.21 592 "
603
615 45 4.8
4.8
4.8 0.6
1.0
1.5 4.47
3.77
2.91 580
592
605 50 5.5
5.5
5.5 0.6
1.0
1.5 5.97
5.27
4.41 557
568
581 7.0 except.
7.0 half
7.0 DIN 1725

The non-standardized alloy with 7% magnesium was included for the following comparisons.

Numerous studies have been carried out to improve this type of alloy. These Investigations are based on the working hypothesis that the aluminum-magnesium-silicon alloys for high loads, especially thermal alternating loads, coordinated Must have magnesium and silicon contents and the free magnesium contents not bound to silicon the solubility of the magnesium in the aluminum at room temperature must not be exceeded indefinitely.

In particular, the use of this type of alloy for cylinder heads gave rise to the consideration that a Crack formation due to the temperatures prevailing in the combustion chamber with higher magnesium contents starts earlier, which is why the magnesium content is reduced to lower concentrations also had to be advantageous for raising the solidus point of the alloys.

Numerous investigations were carried out at the same time as the investigation of the influence of the magnesium content carried out to determine the influences of various alloying elements. The melts were subjected to intensive degassing before casting and only such elements added, the addition of which, according to known studies, does not increase the solubility for hydrogen became. The solidus points in the aluminum-magnesium-silicon system should also not be decisive

Number board 2

lower and the structure refinement is also improved will.

It has been found that when the aluminum-magnesium-silicon alloys are cast in ^{molds at 300 °} C. in accordance with aviation standard LN 29 531, the smaller the magnesium not bound to silicon, the _{finer the Mg 2 Si is obtained} -Content of the alloy, and by an increased manganese content in the absence of cerium and

ίο Zinc an even finer Mg ₂ Si is obtained, which with a low Mg content is only recognized microscopically as the finest precipitate at very high magnification. The influence of manganese on the mechanical values is therefore outstanding at room temperature and higher temperatures. The tensile specimens were previously subjected to a stabilization annealing in the known manner.

Batch analysis in%

Mg

Si

Mn

Fe

Test at 20 "C kp / mm ^{2 c}

ÖO, 2 öS i

Test at 300 ° C
kp / mm ² kp / mm ^{2 0} A

HB pö, 2 tfff = "- * δ:

Test at 400 ° C
kp / mm ² -% "

. 00.2 OB <5s

3.6

3.2

5.2

5.4

6.5

6.6

1.04 0.22 0.31 7.6 17.9 7.4 55 6.1 8.4 78.0 2.8 4.3 46.0 7.9 16.3 4.8 53 6.1 8.9 63.8 2.8 4.7 84.0 5.5 8.4 44.4 Average 7.7 17.1 6.1 54 5.9 8.6 62.1 2.8 4.5 65.0 0.93 0.98 0.3 6.9 20.8 14.3 57 6.4 9.7 42.4 4.1 6.2 78.0 7.1 20.7 14.9 55 4.9 9.1 36.4 5.6 9.0 35.4 Average 7.0 20.7 14.6 56 5.6 9.3 38.1 4.1 6.2 78.0 1.02 0.93 0.3 10.3 22.2 7.1 64 8.2 11.7 30.6 4.1 6.2 84.0 10.0 21.0 6.0 64 6.4 11.0 25.8 7.6 10.5 25.4 Average 10.1 21.6 6.5 64 7.4 11.1 27.3 4.1 6.2 84.0 1.02 0.93 0.38 12.9 26.5 8.5 69 9.7 13.6 71.4 5.3 7.8 could not b. will. 12.1 26.9 10.8 72 10.7 13.4 33.2 5.3 7.8 83.4 6.2 11.0 41.2 Average 12.5 26.7 9.6 70 8.9 12.7 48.6 5.3 7.8 83.4 1.10 0.22 0.23 12.9 23.2 5.1 72 8.7 14.1 could 4.1 6.7 85.2 not b. will. 13.1 23.5 5.3 72 10.1
9.9
9.6 14.7
12.7
13.8 25.6
ion Average 13.0 23.3 5.2 72 9.9 13.9 lo, U
21.8 4.1 6.7 85.2 1.17 0.9 0.36 13.7 23.2 4.0 74 9.2 14.6 24.8 5.1 7.9 97.0 13.7 24.2 4.9 76 9.4 13.6 18.0 9.5 14.0 18.6 Average 13.7 23.5 4.4 75 20.5 5.1 7.9 97.0

The addition of manganese should not exceed the maximum solid solubility known in the aluminum-manganese system in addition, but also not below 0.6%.

The refinement of the Mg ₂ Si by manganese has nothing in common with the molding of the stuffy, needle-like iron aluminides by manganese in aluminum-silicon alloys with low magnesium contents from zero to about 0.6%. It is true that in aluminum-magnesium-silicon alloys with Fe contents of 1.25%, such contents usually occur as impurities in such cast alloys when scrap with inevitably high admixtures is added, and these are among the permissible impurities according to DIN 1725 from June 1959, Die-Cast Alloys, sheet 2, page 8, count, according to which the alloys GD-AlMg 9 and GD-AlMg 8 (Cu) can contain 0.6 to 1.2% iron, due to higher manganese contents Mg ₂ Si can be refined, but not, as with aluminum-silicon alloys, such molding of the iron aluminide into a multi-substance compound. The alloys have lower elongation and strength values, as the number table 3 shows.
The narrow-minded formation of iron aluminide found in aluminum-magnesium-silicon alloys according to table 3 is not canceled out by an increased addition of manganese in the ternary aluminum-silicon-magnesium alloys with around 13% silicon and 6% magnesium. These investigations

bo also do not show any outstanding technical progress in terms of strength values Combination with manganese, but also that when it is used in the presence of large quantities Silicon and larger amounts of magnesium have the effect of manganese not that of those in aluminum-silicon alloys with up to 0.6% or without magnesium is comparable. See number table 4.

Analysis in ° / o
Mg Si 1.35 13.57 5 Mn Fe 14th 16.1
18.8
17.4 16.9
17.0
16.9 83 229 Exam at 300 ^c
kp / mm ²
00.2 OB 9.5
8.9
9.2 7.6
7.6 6th Test at 400 °
kp / mm ²
00.2 OB 4.8
sä
5.0 5.0
5.0 C.
%
ÖS 3.85 1.10 13.11 0.21 0.29
Average 17.1
15.4
16.2 16.8
17.2
17.0 5.3
5.3
5.3 10.7
9.9
10.3 9.2
9.2 3.1
2.8
2.9 6.5
6.5 4.2
4.2 79.0
81.0
80.0 Number board 3 3.8 1.05 12.95 Mn Fe 0.75 0.2
Average Test at 20 °
kp / mm ²
00.2 Ob 22.7
22.5
22.6 12.2
11.6
11.9 C.
° / o kp / mm ²
HB 6.3
4.8
5.5 12.6
11.6
12.1 8.8
8.8 C.
%
'H 3.6
3.6 6.7
6.7 6.4
6.4 65.0
65.0 Batch
No. 5.3 1.14. 12.62 0.25 1.25
Average 0.22 1.3
Average 8.8
8.9
8.8 18.5
18.5
18.5 13.7
14.8
14.2 2.8
4.3
3.6 57
58
57 8.4
8.5
8.3 13.1
11.6
12.3 8.4
8.4 41.8
47.2
44.5 4.1
4.1 7a
7a 5.8
5.8 98.2
98.2 851 5.5 0.92 0.9 1.25
Average 0.83 1.3
Average 9.4
9.3
9.3 19.2
22.8
21.5 3.0
2.1
2.5 64
62
63 9.4
7.6
8.5 14.2
13.8
14.0 12.2
8.6
10.4 4.2
4.2 ea
6.2 73.4
73.4 857 6.85 1.06 0.22 1.14
Average 10.8
10.5
10.6 18.8
17.8
18.3 4.8
5.0
4.9 71
71
71 9.4
9.4
9.4 14.7
14.5
14.2 42.0
33.8
37.9 3.6
3.6 7.9
7.9 " 64.6
64.6 .853 7.0 0.82 1.00
Average 10.3
10.6
10.4 3.1
2.9
3.0 67
72
69 9.2
9.2
9.2 7.8
8.8
7.3 4.1
4.1 83.2
83.2 859 Number board 4 Analysis in%
Mg Si 0.22 1.12
Average 12.4
12.4
12.4 Test at 20 °
kp / mm ²
Ö0.2 OB 2.4
4.5
3.4 76
76
76 Test at 300 °
kp / mm ²
Oq ₂ OB 12.8
17.0
14.9 Test at 400 °
kp / mm ²
002 ⁰ B 855 Batch
No. 6.0 0.87 1.20
. Average 14.1
13.9
14.0 9.6
9.5
9.5 1.8
1.3
1.5 84
90
87 * 3.8
3.8 4.2
3.2
4.9 2.4
2.4 C.
%
<5s 861 888 6.5 _ 10.9
10.5
10.7 5.6
5.6 2.7
2.7 20.0
20.0 886 5.25 10.9
10.6
10.7 C.
o / o
<5s kp / mm ²
HB 3.0
3.0 C.
% 2.9
2.9 20.0
20.0 889 5.6 10.8
10.5
10.6 3.0
2.8
2.9 60
58
59 6.3
6.3 11.6
11.6 3.2
3.2 3.0
3.0 887 2.0
2.4
2.2 66
69
67 11.2
11.2 τα
τα 1.1
0.8
0.9 71
69
70 1.8
1.8 1.4
1.8
1.6 71
72
71 3.4
3.4

According to these investigations it was therefore surprising that with very high magnesium contents of about 9 to 10% and silicon contents of about 3% with free magnesium contents not bound to silicon between 3 and 4% even with higher iron contents of 1.20%, as is often the case after the usual Feeding of scrap occurs, iron needles no longer occurred, provided higher manganese contents were added became.

However, in the presence of high levels of iron of 1.20%, there are no significant changes in the Strength values have been caused. In the case of alloys with a low iron content, the Manganese species, in addition to a strong structure refinement, is a considerable one associated with it Increase in strength values recorded. The number table 5 shows the improvement in strength values by Manganese in alloys, which are found on the melt channel between the ternary magnesium and silicon rich Eutectics of the system aluminum - silicon - magnesium and preferably on the magnesium-rich side and contain silicon contents below that of the quasi-binary eutectic with 13% Mg2Si. Preferably are silicon contents between 2.5 and 4% and a maximum of 11% magnesium in the presence of manganese to alloy.

The investigations were carried out on alloys with magnesium contained in the alloy. The machinability of castings made from these alloys is worse.

To solve the problem, the use of AlMgSi cast alloys, consisting of 0.6 to 4.5% silicon, 2.5 to 11% magnesium, the remainder Al with the usual production-related impurities with the proviso that within of the specified ranges, the ratio of magnesium to silicon is coordinated so that 1 to 4.5% of the magnesium is not bonded to silicon, 0.6 to 1.8% manganese, the remainder aluminum with silicon contents of 2% and Magnesium contents extended from 4%. The strong refinement of the Mg ₂ Si by manganese is also achieved (see table of figures 6).

With around 4% magnesium and 2% silicon, there is only 0.55% of the usual production-related impurities not bonded to silicon, and up to 0.6% copper as a permissible admixture as a high-strength material for thermal use with a refined _{Mg 2 Si component} alternately stressed cylinder heads are proposed, which with a thermal alternating ^{stress between 100 to 300 0} C withstand more than 1050 load changes within 120 seconds up to the crack and must be easily machinable.

Further results were obtained from the verification the influence of nickel, which is similar to that

Manganese shows the lowest hydrogen solubility at contents of about 1% in the aluminum in the melt flow and was therefore also selected for alloy tests. It has been found that in contrast to the 1.5% nickel gives copper a very fine magnesium silicide and that of the magnesium silicide The coarse influence of copper in the presence of nickel is canceled. Investigating the Strength properties in the tensile test showed that the stabilized alloys when the io

Number board 5

Mg contents of 4% only have low elongation values and the aluminum-magnesium-silicon alloys have less than 4% magnesium in the presence of nickel and / or greater amounts than 0.2% copper must (see number table 7).

It is therefore also proposed to use an AlMgSi alloy according to the invention in the above composition with the proviso that it contains up to 2% Ni.

Batch analysis in% Mg Si Mg Si Si Mn Mn Fe 0.24 0.30 0.32 1.20 1.12 Ni Check at 20 ^s Cu IF Fe 0.42 0.4 0.34 0.37 0.29 0.29 'C o / o kp / mm ² if IF C. Test at 300 ° if C. Test at 400 ° C IF 002 o / o IF o / o IF o / o No. 9.7 3.1 3.95 2.0 1.17 0.27 0.28 0.2 kp / mm ² 26.0 0.41 Ö5 HB 20.8 17.8 kp / mm ² 12.8 % kp / mm ² 6.1 4.1 <5 ₅ 7.7 05 5.8 05 Average Average Average Average Average 00.2 22.9 Average Average Average Average Average 3.4 9.2 20.7 17.6 O02 13.6 05 002 43.4 74.8 89.4 871 Average 0.32 0.88 0.30 1.03 14.9 24.4 Average 1.45 1.2 1.25 2.1 92 20.7 17.7 8.4 13.2 27.4 3.6 6.1 4.4 31.8 7.7 5.8 9.44 2.7 4.2 1.9 1.15 0.25 0.85 14.9 27.5 - 2.7 92 23.0 18.6 9.2 16.2 24.0 8.5 4.9 37.4 7.5 74.8 6.5 89.4 14.9 27.2 2.8 95 22.1 18.6 8.8 15.6 25.7 3.6 28.0 61.6 7.3 n.b. 873 Mn 18.1 27.3 Fe 2.4 98 22.5 18.6 12.2 15.9 35.4 4.8 8.5 4.9 27.2 7.5 6.9 96.0 - 8.6 3.3 Number board 7 1.0 0.24 0.24 18.2 19.8 0.39 2.6 96 22.3 11.2 132 = - 13.6 27.6 -61.6 - 8.0 96.0 Char- Analysis in% 18.1 20.3 1.8 80 21.8 lt, 7 11.7 24.5 4.8 Test at 300 ° C 16.8 34.6 947 gene-
No. • 11.9 20.0 Average 2.0 78 22.0 % 9.2 12.8 25.0. ■ - kp / mm ² 8.6 8.0 8.8 3.6 Mg 1.03 0.23 1.00 12.1 25.3 1.9 79 20.4 Ö5 8.2 13.9 30.0 002 Ob 12.7 - 5.9 34.6 862 3.7 12.0 25.4 3.0 83 20.4 4.1 8.7 13.1 27.5 - 5.8 10.5 49.6 87.6 948 14.0 25.3 2.6 87 20.4 5.0 9.2 13.5 19.6 - 5.8 10.1 44.0 5.9 9.25 3.1 1.08 0.23 13.8 24.2 2.8 85 24.0 4.5 9.6 14.3 23.6 7.4 5.8 10.3 46.8 - 6.5 87.6 863 5.5 13.9 25.8 3.5 101 23.4 4.4 9.4 14.3 21.8 - 8.2 12.4 40.8 83.6 100.0 872 16.0 25.0 3.1 91 23.7 4.8 9.4 14.6 26.6 4.1 7.4 9.4 13.4 33.8 6.5 9.7 2.75 1.12 0.25 Cu 15.6 23.5 3.3 96 24.8 4.6 9.2 17.6 15.2 8.1 8.6 12.9 37.3 83.6 7.2 100.0 864 7.0 1.5 15.8 24.8 2.3 108 25.5 2.6 9.3 14.9 19.7 4.1 9.9 14.3 21.6 65.2 131.2 874 18.4 24.1 2.4 98 1.9 13.5 16.2 5.2 5.1 8.1 9.6 13.8 21.4 Number board 6 17.9 2.3 103 2.2 8.1 6.6 9.8 14.1 65.2 Batch analysis in% 865 3.4 1.35 18.1 8.0 10.8 5.9 5.1 Test at 300 ° C 6.7 10.6 No. Test at 20 ° 8.9 kp / mm ² kp / mm ² 5.8 10.1 kp / mm ² 8.4 HB 6.2 10.3 o / o 940 866 5.6 1.5 00.2 5.6 % 54 8.9 12.7 05 8.2 6.0 • 5? 55 8.9 13.6 39.2 8.1 5.8 5.5 54 8.9 13.1 944 867 7.1 ' 8.1 3.8 5.4 58 9.9 15.2 39.2 8.6 4.1 5.4 62 10.1 145 52.0 8.8 5.0 60 . 8.7 4.8 52.0 4.9 Test at 20 ° C Test at 400 ° C kp / mm ² kp / mm ² ' 002 kp / mm ² 002 10.2 HB 3.3 10.1 67 10.1 69 3.3 11.4 68 3.5 11.7 72 3.7 11.5 74 3.6 14.4 73 4.8 14.2 80 14.3 83 4.8 8.6 81 3.1 8.6 61 8.6 60 3.1 11.1 60 3.8 10.9 76 11.0 74 3.8 14.4 75 4.1 14.4 85 87

030 216/2

14 ÖJ 9

The present results were transferred to the use of these AlMgSi alloys for cylinder heads, which were subjected to alternating heating and cooling in their highly stressed areas on a test stand until cracking occurred. The thermal cycle load between 100 and 300 ⁰ C to cracking and through crack was regarded as a measure of the resilience of the alloys.

The figure shows, among other things, the thermal ι ο alternating load test of cylinder heads from the Usual alloy AlMg 5 Si 1 Cu 0.5 according to number table 8 again. These cylinder heads are one taken from normal production over a period of several months. It was an average number of thermal alternating loads from 716 to the crack or from 769 to Breach found.

Usually an alloy according to DIN has been used up to now

10

1725 (1959), sheet 2, used. In contrast, there were cylinder heads made of a material according to Invention were cast and showed a fine structure, the structure of the alloys with lower and higher magnesium contents, similar to the die cast test rods according to LN 29 531 was trained in the same way for the examination. The figure and number table 9 contains the thermal Fluctuating numbers. From the investigations it can be seen that with compared to the usual Alloy with comparable silicon content and the usual admixture of 0.5% Cu the alloys With a high magnesium content, a significantly shorter running time, even with an additional manganese compound and when comparing the results with the conventional alloy, see figure and Number tables 8 and 9, the alloys with a higher manganese content show a clear improvement.

= 3

• ng

H c

IU

-C

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

200

100

\ O
\O X - ^ - - - · \ 0 T \% Mg total 5.5
% Mg total 4.55 I I. O\ % Mg total 5.14
DIN 1725: 4-5.5% % Mg total 7.4 O\ O O mean \

O

0.98-1.00% Si 0.89-0.92% Mn 0.50-0.55% Cu 0.15% Ti 0.33-0.45% Fe 0.004% Be remainder Al % Mg not an Si bound
Other alloy components:

Xhach DIN 1725

0.94-0.99% Si

0.36% Mn
0.52-0.55% Cu

nb% Ti
0.43-0.45% Fe

n.d.% Be

Rest all inclusive

DIN 1725

0.5-1.5% Si

0-0.5% Mn

0-0.6% Cu
0-0.20% Ti

-0.5% Fe

- Be

Remainder Al

The diagram in the illustration shows an almost linear dependency between the number of thermal load cycles and magnesium content and that a max. Improvement according to the invention by 100% is possible. Alloy No. 3 in number table 9 and in the Figure has a free magnesium content of around 5.7%, alloy No. 2 has a content of 3.77% and Alloy No. 1 only 2.85%. Alloys 4 and 5 in number table 9 contain only about 0.9% free magnesium. Alloy 5 shows a significantly higher thermal rating after adding manganese Resilience, the comparison with the alloys of the number table 8 provides information about the after degradation of the free magnesium content achieved high thermal resistance The free magnesium content of the Alloys 4 and 5 are very low at 0.9%. the

Number board 8

Machinability of these alloys was poor on a production line. The free magnesium content should not fall below 1%.

All the tests show that the free magnesium content of the aluminum-magnesium alloys to achieve a high load capacity, especially a thermal alternating load, between 1 and 4.5, preferably 1 to 3.0% should be.

When using an alloy within the meaning of the present invention, the silicon content should be at least 1% amount, the manufacturing process including a kneading process.

When using the AlMg-Si alloys according to the invention, it is advantageous to use them before casting intensive degassing.

Trial no.

Analysis in ° / o

Mg Si

Mn

Fe

Thermal alternating stress

1 . 5.06 2 3 4th 5 5.19 6th 7th 8th 9 5.16 10 11th 12th 13th 14th 15th 16 Average 5.14

0.94

0.99

0.95

0.36

0.36

0.36

0.45 -—rr-. _.

0.44

0.43

n.b. 709 639 * 670 894 960 940 1050 450 640 775 877 707 872 574 736 640 663 n.b. 760 830 880 n.b. 650 n.b. 720 n.b. 660 n.b. 671 n.b. 800

0.96

0.36

0.44

-716

-769

(n.b. = cannot be precisely determined.)

Number board 9

Analysis in%

Mg Si

Mn

Cu

Fe Ti

Be

Thermal alternating stress

1 4.55 0.99 0.91 0.50 0.42 0.15 0.004 1450
1350 1600
1500 2 5.5 1.00 0.92 0.50 0.32 0.15 0.004 800
1200 890
1224 3 7.4 038 0.89 0.55 0.33 . 0.15 0.003 nb
nb 168
335 4th 4.4 2.08 0.02 0.17 0.20 0.15 0.004 1040
930
nb 1160
1030
1100 5 4.3 1.88 0.78 0.15 0.21
* 0.15 0.004 1380
1380
1360 1590
1420
1410

(n. d. r = cannot be precisely determined.)

Claims (4)

14 claims: 1. Use of AlMgSi cast alloys, consisting of 0.6 to 4.5% silicon, 2.5 to 11% magnesium, with the proviso that the ratio of magnesium to silicon is coordinated within the specified ranges that 1 to 4.5% magnesium is not bound to silicon, 0.6 to 1.8% manganese, the remainder aluminum with the usual production-related impurities, and up to 0.6% copper as a permissible addition, as a high-strength, in the component mg ₂ Si gefeinter material for thermal cycle stressed cylinder heads, the more than 1050 to withstand load change and at a thermal cycling test between 100 to 300 ⁰ C within 120 seconds to the through crack must be easy to machine. 2. Use of an alloy of the composition according to claim 1, which contains up to 2% nickel, for the purpose of claim 1. 3. 'Use of an alloy of the composition according to claim 1 and 2 with the proviso, that the silicon content is at least 1%, for the purpose according to claim 1, wherein the production sequence includes a kneading process. 4. Use of an alloy of the composition according to claim 1 to 3, which before Potting has been intensively degassed for the purpose of claim 1. Heat resistance was determined, which could be improved by other alloy elements. These and other numerous studies have resulted in the use of aluminum-magnesium-silicon alloys led to the 2 to 5.5% magnesium, 0 to 1.5% silicon, 0 to 0.5% manganese and 0 to 0.20% titanium contain. For heat-resistant purposes, mainly cylinder heads, ·., An aluminum alloy came with the pre-fill foundries -selected, almost identical Composition 4.8 to 5.5% magnesium, 0.8 to 1.2% silicon, 0 to 0.6% copper and the above manganese contents for delivery. Depending on the agreement with the consumer, these alloys are for restraint Small amounts of beryllium have been added to the oxidation. These alloys are in the DIN 1725 from June 1959, sheet 2. From the German patent 7 47 355 are alloys consisting of 4 to 12% magnesium, 0.5 up to 5% silicon, each 0.2 to 5% copper and / or nickel, the remainder aluminum, known, which also contain iron, cobalt, Manganese, chromium, molybdenum, titanium and cerium can individually contain up to 3.5%, in total up to 7%. Targeted usability in accordance with the registration selected alloys cannot be taken from it. Both the tolerance for the magnesium and silicon contents of these alloys allow the most varied Combinations so that quite different amounts of magnesium silicide can be formed and magnesium not bonded to silicon is found in the alloys, as indicated by the number table 1 is shown.