Aluminum casting alloy
A cast aluminum alloy contains at least five of the following alloy components: 2.5 to 3.3 wt.-% of Si; 0.2 to 0.7 wt.-% of Mg; <0.18 wt.-% of Fe; <0.5 wt.-% of Mn; <0.1 wt.-% of Ti; <0.03 wt.-% of Sr; 0.3 to 1.3 wt.-% of Cr; and <0.1 wt.-% of others, supplemented by Al to add up to 100 wt.-%. The parts cast from the alloy are preferably homogenized by annealing for 1 to 10 hours at 490° C. to 540° C. and tempered for 1 to 10 hours at 150° C. to 200° C. Preferably, the alloy is used for chassis parts in motor vehicles.
1 . An aluminum casting alloy that contains at least five of the alloy components listed below
Si: 2.5 to 3.3 wt.-%;
Mg: 0.2 to 0.7 wt.-%;
Fe: <0.18 wt.-%;
Mn: <0.5 wt.-%;
Ti: <0.1 wt.-%;
Sr: <0.03 wt.-%;
Other: <0.1 wt.-%
wherein Cr in an amount that increases alloy strength is contained as another alloy component, supplemented to 100 wt.-% with Al.
2 . The aluminum casting alloy according to claim 1 , wherein Si is present in the amount of 2.7 to 3.1 wt.-%.
3 . The aluminum casting alloy according to claim 1 , wherein Mg is present in the amount of 0.3 to 0.6 wt.-%.
4 . The aluminum casting alloy according to claim 1 , wherein Fe is present in the amount of 0.05 to 0.16 wt.-%.
5 . The aluminum casting alloy according to claim 1 , wherein Mn is present in the amount of 0.05 to 0.4 wt.-%.
6 . The aluminum casting alloy according to claim 1 , wherein Ti is present in the amount of 0.01 to 0.08 wt.-%.
7 . The aluminum casting alloy according to claim 1 , wherein Sr is present in the amount of 0.01 to 0.03 wt.-%.
8 . The aluminum casting alloy according to claim 1 , wherein Cr is present in the amount of 0.3 to 1.3 wt.-%.
9 . The aluminum casting alloy according to claim 1 , wherein Cr is present in the amount of 0.4 to 1.0 wt.-%.
10 . The aluminum casting alloy according to claim 1 , wherein Cr is present in the amount of 0.5 to 0.8 wt.-%.
11 . The aluminum casting alloy according to claim 1 , wherein the at least five of the alloy components are present in amounts listed below
Si: 2.7 to 3.1 wt.-%;
Mg: 0.3 to 0.6 wt.-%;
Fe: 0.05 to 0.16 wt.-%;
Mn: 0.05 to 0.4 wt.-%;
Ti: 0.01 to 0.08 wt.-%;
Sr: 0.01 to 0.03 wt.-%.
12 . An aluminum casting alloy that contains at least five of the alloy components listed below
Si: 2.5 to 3.3 wt.-%;
Mg: 0.2 to 0.7 wt.-%;
Fe: <0.18 wt.-%;
Mn: <0.5 wt.-%;
Ti: <0.1 wt.-%;
Sr: <0.03 wt.-%;
Cr: 0.3 to 1.3;
Other: <0.1 wt.-%
and supplemented to 100 wt.-% with Al.
13 . The aluminum casting alloy according to claim 12 , wherein the at least five of the alloy components are present in amounts listed below
Si: 2.7 to 3.1 wt.-%;
Mg: 0.3 to 0.6 wt.-%;
Fe: 0.05 to 0.16 wt.-%;
Mn: 0.05 to 0.4 wt.-%;
Ti: 0.01 to 0.08 wt.-%;
Sr: 0.01 to 0.03 wt.-%;
Cr: 0.4 to 1.0 wt.-%.
14 . The aluminum casting alloy according to claim 12 , wherein the at least five of the alloy components are present in the amounts listed below
Si: 2.7 to 3.1 wt.-%;
Mg: 0.3 to 0.6 wt.-%;
Fe: 0.05 to 0.16 wt.-%;
Mn: 0.05 to 0.4 wt.-%;
Ti: 0.01 to 0.08 wt.-%;
Sr: 0.01 to 0.03 wt.-%;
Cr: 0.5 to 0.8 wt.-%.
15 . The aluminum casting alloy according to claim 12 , wherein in addition, CuNi is contained as an additional alloy component, by being alloyed in at the same time, supplemented to 100 wt.-% with Al.
16 . A method of producing a part comprising
(a) forming a cast part from an aluminum casting alloy containing at least five of the alloy components listed below
Si: 2.5 to 3.3 wt.-%;
Mg: 0.2 to 0.7 wt.-%;
Fe: <0.18 wt.-%;
Mn: <0.5 wt.-%;
Ti: <0.1 wt.-%;
Sr: <0.03 wt.-%;
Other: <0.1 wt.-%
wherein Cr in an amount that increases alloy strength is contained as another alloy component, supplemented to 100 wt.-% with Al; and
(b) solution-annealing the cast part between 490° C. to 540° C. for 1 to 10 hours.
17 . The method according to claim 16 , wherein the cast part is annealed between 150° C. to 200° C. for 1 to 10 hours.
18 . The method according to claim 16 , wherein the Al casting alloy is grain-refined.
19 . The method according to claim 16 , further comprising using the part to form a work piece.
20 . The method according to claim 16 , further comprising using the part to form a component of a motor vehicle chassis.