BS EN 1706-2020 Aluminium and aluminium alloys – Castings – Chemical composition and mechanical properties.
7.2 Tensile tests
Tensile tests shall be carried out in accordance with EN ISO 6892-1.
7.3 Test pieces
7.3.1 General
This document does not specify the exact design of test pieces that shall be agreed between supplier and purchaser. The use of existing rules or standards is recommended until a suitable European Standard is published. However, the following conditions shall apply.
7.3.2 Separately cast test samples
7.3.2.1 General
When tensile tests are required on separately cast test samples, these test samples shall be cast at the same time and from the same melt or melts as the castings, using the same casting process. When applicable, they shall be heat treated with the castings.
NOTE Separately cast test pieces have a valuable function as a check on melt quality. However, the values obtained from castings can differ from the minimum values specified in the tables because of variations in structure arising from differences in section thickness and soundness (see 7.3.3).
7.3.2.2 Sand cast test pieces
The following conditions apply to sand cast test pieces:
1) they shall be cast in sand moulds, having comparable thermal properties to the moulding material used to the castings;
2) as cast diameter shall be a minimum of 12,0 mm;
3) the gauge length and parallel length shall conform to EN ISO 6892-1.
Test pieces may be tested in the machined or unmachined condition.
7.3.2.3 Chill cast test pieces
The following conditions shall apply to chill cast test pieces:
1) they shall be cast into metallic moulds;
2) as cast diameter shall be a minimum of 12,0 mm;
3) the gauge length and parallel length shall conform to EN ISO 6892-1.
Test pieces may be tested in the machined or unmachined condition.
7.3.2.4 Investment cast test pieces
The following conditions shall apply to investment cast test pieces:
1) they shall be cast entirely into ceramic moulds without artificial chilling;
2) as cast diameter shall be a minimum of 5,0 mm;
3) the gauge length and parallel length shall conform to EN ISO 6892-1.
Test pieces may he tested in the machined or unmachined condition.
7.3.2.5 High pressure die cast test pieces
High pressure die cast test pieces are normally not produced. Testing the entire casting with loads
reflecting the intended service conditions is more meaningful.
The values given in Table A.1 are for information only. These are not typical values, but are the minimum values that may be expected from separately high pressure die cast test pieces of 20,0 mm2 cross sectional area with a typical wall thickness of 2,0 mm.
7.3.3 Test pieces taken from castings
7.3.3.1 If test pieces are taken from castings, their geometry, location, test frequency and relevant values shall be agreed between supplier and purchaser. For round test pieces the minimum diameter shall be 4,0 mm.BS EN 1706 pdf download.