AluCAD I - Aluminium Cast Alloy Development I

Purpose and goal: Objective

To generate increased knowledge for the development of scrap-based in-cast hardenable and age-stable aluminum alloy with high castability. To increase Rp as cast stable by 50% with min 10% elongation at break rel existing alloys. Mechanical goal fulfillment 30% Strength Rp 120 rel objective ca 150 Mpa and elongation A5 10%

Competence alloy & microstructure goal fulfillment 40 % Precipitation composition identified Alloy element microstructure formation identified and individual hardening potential identified (sigma) Possible solution hardeners determined Expected results and effects: Strength Rp / A5 + 30% rel ref in cast condition despite increased Fe

Aged min 15 or 5% higher Rp / A5 despite increased Fe, i.e. primary properties. Alloying and melt purification can increase secondary properties to above primary properties without heat treatment Expected effects With melt purification and alloying, the potential for a secondary alloy is 30% higher Rp than the corresponding primary alloy

75% of the Rp but 30% higher A5 than corresp hardened primary alloy CO2 saving alloyed secondary Al can provide an annual net reduction of CO2 emissions of 450 kTon for one car manufacturer Approach and implementation:

Test plan was established for sequential casting of alloys with the aim of identifying solution hardeners or stable precipitation hardeners 2 test loops were planned so that a first test result could be used in a second test. Rheocasting is chosen as test method due to the relatively low CO2 footprint of the process.

In selection of alloying substances the influence of the elements on strength individually and in combination was assesed. The alloy choices are based on individual and combined effects of the elements on microstructure and properties.