AS 1663-1974

1 - AS 1663-1974 DROPWEIGHT TEST FOR NIL-DUCTILITY TRANSITION TEMPERATURE OF FERRITIC STEELS (METRIC UNITS)
4 - PREFACE
5 - CONTENTS
6 - SECTION 1. SCOPE AND DEFINITIONS
6 - 1.1 SCOPE.
6 - 1.2 DEFINITIONS.
6 - 1.2.1 Sample
6 - 1.2.2 Test Specimen
6 - 1.2.3 Test Piece
6 - 1.2.4 Nil-ductility Transition Temperature (NDTT)
6 - 1.2.5 Dropweight Machine
7 - 1.2.6 Crack-starter
7 - 1.2.7 Brittle Weld Crack-starter
7 - 1.2.8 Cold Pressed and Aged Crack-starter
8 - SECTION 2. TEST SPECIMENS AND TEST PIECES
8 - 2.1 TEST SPECIMENS.
8 - 2.1.1 Identification and Marking.
8 - 2.1.2 Size of Test Specimens.
8 - 2.1.3 Location of Test Pieces.
8 - 2.1.4 Condition of Test Material.
9 - 2.2 TEST PIECES.
9 - 2.2.1 Dimensions.
9 - 2.2.2 Cutting.
9 - 2.2.3 Identification.
10 - SECTION 3. PREPARATION OF CRACK-STARTER
10 - 3.1 SELECTION OF CRACK-STARTER.
10 - 3.2 PREPARATION OF BRITTLE WELD CRACK-STARTER.
10 - 3.2.1 Weld Bead Location.
10 - 3.2.2 Welding.
11 - 3.2.3 Notching.
11 - 3.2.4 Alternative Brittle Weld Crack-starters.
11 - 3.3 PREPARATION OF COLD PRESSED AND AGED CRACK-STARTER.
11 - 3.3.1 Test Piece Preparation.
12 - 3.3.2 Ageing.
14 - SECTION 4. TESTING MACHINE
14 - 4.1 GENERAL ARRANGEMENT.
14 - 4.2 DROPWEIGHT.
14 - 4.3 ANVILS.
14 - 4.4 GUIDES.
14 - 4.5 RELEASE.
14 - 4.6 BASE.
14 - 4.7 SAFETY DEVICES.
19 - SECTION 5. TEST PROCEDURE
19 - 5.1 CONDITIONING OF TEST PIECE.
19 - 5.2 ACCURACY OF TEMPERATURE OF BATH.
19 - 5.3 TEST TEMPERATURES.
19 - 5.4 STOP DISTANCE.
19 - 5.5 DROP ENERGY AND HEIGHT.
19 - 5.6 TESTING.
21 - SECTION 6. EXAMINATION OF TESTED TEST PIECES AND SUBSEQUENT ACTION
21 - 6.1 FEATURES OF EXAMINATION.
21 - 6.2 CRITERIA.
21 - 6.2.1 ‘Break’.
21 - 6.2.2 ‘No Break’.
21 - 6.2.3 ‘No Test’.
22 - 6.3 DETERMINATION OF NDTT.
23 - 6.4 ROUTINE PROVING TEST.
26 - SECTION 7. RECORDING AND REPORTING OF TESTS
26 - 7.1 RECORD OF RESULTS.
26 - 7.2 TEST REPORT.

Outlines the method of conducting the NDTT test on ferritic steels which show a fracture surface appearance transition from brittle to ductile. It describes methods for test piece preparation, gives dimensions of the brittle-weld bead crack-starter and the procedure for carrying out the test.

This standard describes the method of conducting the dropweight test for the determination of the nil-ductility transition temperature (NDTT) of ferritic steels which show a fracture appearance transition from brittle to ductile accompanied by a substantial change in fracture energy with rise in temperature. The test is applicable to plates, forgings, castings, sections and welded joints, where the thickness is 16 mm or greater.NOTE: With special modifications to the test and by agreement between the parties concerned on the interpretation of the results, the test has been used on thicknesses down to 12 mm and on test pieces of thickness greater than the standard test piece.Reference: PUZAK, P.P. and BABECK, A.J., 'Normalization Procedures for the NRL Drop-weight Test',Welding Journal, May 1959.The test consists of dropping a weight on to a test piece in the form of a simply supported beam having an embrittled notch on the tension surface to determine the highest temperature at which the test piece fractures to one or both edges of the tension surface.

Reconfirmed 1989