AS 2205.7.2-2003 pdf free.Methods for destructive testing of welds in metal – Method7.2:Dropweight fracture toughness test for nil-ductility transition temperature.
This Standard sets out a method for dropweight testing of a welded joint to determine the nil-ductility transition temperature of a selected area of metal in the weld zone.
NOTE: For the purposes of this Standard, welding consumables are taken to mean electrodes, filler metals, fluxes and gases.
2 REFERENCED DOCUMENT
The following document is referred to in this Standard:
AS
1663 Method for dropweight test for nil-ductility transition temperature of ferritic steels
3 PRINCIPLE
A test specimen is prepared and tested in a specified manner and the nil-ductility transition temperature of a selected area of metal in the weld zone is determined.
4 PREPARATION OF TEST SPECIMEN
4.1 Type and dimensions
The shape, dimensions and method of preparation of the test specimen shall be in accordance with AS 1663.
4.2 Location of specimen
The location and orientation of the test specimen and the notch relative to the weld shall be one of the positions shown in Figure 1. or as specified in the application Standard. A transverse section of the specimen shall he etched to distinguish between the weld metal, heat-affected zones and the parent metal, to ensure that the notch will be located correctly.
For routine production testing, the notch shall be located in the zone or zones of the welded joint that was shown by the assessment of the welding procedure to have the highest (i.e. poorest) NDTT.
4.3 Test Piece
4.3.1 Size of test piece
The test piece shall permit the taking of eight test specimens of the same orientation from each part of the weld for which determination of NDTT is required.
For assessment of welding procedures, sufficient length of weld shall be supplied, to permit the NDTT to be established for each significantly different zone of the weld (e.g. for each weld run where necessary).
Alternatively, for routine production testing and where otherwise specified, assessment may be limited to demonstrating that the NDTT is below the lowest permitted NO-BREAK temperature (test performed 5°C above the specified NDTT). Run-on/run-off tabs welded as dropweight specimens for each routine are sufficient test material.
4.3.2 Alignment
Parent material shall be prepared, so that the edges to be welded are aligned within 2 mm and the test piece is flat within 5 mm per 300 mm both parallel and transverse to the weld axis.