AS 1391-1991

1 - AS 1391-1991 METHODS FOR TENSILE TESTING OF METALS
4 - PREFACE
5 - CONTENTS
6 - 1 SCOPE
6 - 2 REFERENCED DOCUMENTS
6 - 3 DEFINITIONS
6 - 3.1 Elongation
6 - 3.2 Extension
6 - 3.3 Extensometer
6 - 3.4 Gauge length
7 - 3.5 Maximum force (Fm )
7 - 3.6 Percentage reduction of area after fracture
7 - 3.7 Permanent set stress (Rr)
7 - 3.8 Proof elongation
7 - 3.9 Proof stress
7 - 3.10 Proving test
7 - 3.11 Strain
7 - 3.12 Stress
7 - 3.13 Tensile strength (Rm)
7 - 3.14 Test piece
7 - 3.15 Test sample
7 - 3.16 Test specimen
7 - 3.17 Yield
8 - 4 NOTATION
8 - 5 SELECTION, POSITION AND PREPARATION OF TEST PIECES
8 - 5.1 General
8 - 5.2 Selection and positioning of test pieces
10 - 5.3 Separation of test specimen and test piece from test sample
10 - 5.4 Straightening test specimens or test pieces
10 - 5.5 Surface finish of test piece
10 - 5.6 Removal or retention of surface coatings or layers
10 - 6 DIMENSIONS OF TEST PIECES
10 - 6.1 General
11 - 6.2 Proportional test pieces of circular cross-section
11 - 6.3 Test pieces of rectangular cross-section
12 - 6.4 Product section test pieces
12 - 6.5 Test pieces from tube
13 - 6.6 Gripped ends
13 - 7 DETERMINATION OF CROSS-SECTIONAL AREA
13 - 7.1 Accuracy of measurement
13 - 7.2 For unmachined bar and uniformly parallel sections
13 - 7.3 For curved test pieces
13 - 7.4 For full-section round tubing
13 - 8 GAUGE LENGTH
13 - 8.1 Original gauge length
13 - 8.2 Extensometer gauge length
13 - 9 METHODS OF GRIPPING
14 - 10 TEMPERATURE OF TEST PIECE
14 - 11 ACCURACY OF TESTING EQUIPMENT
14 - 11.1 General
14 - 11.2 Force-measuring system
14 - 11.3 Extensometer
14 - 12 STRAIN RATE
14 - 12.1 General
14 - 12.2 Elastic strain rate
15 - 12.3 Plastic strain rate
15 - 13 DEFORMATION AND FRACTURE POSITION
15 - 13.1 General
15 - 13.2 For acceptance testing
16 - 14 DETERMINATION OF YIELD STRESSES (ReH , ReL)
16 - 14.1 Specified properties
16 - 14.2 Methods
16 - 14.3 Alternative values
16 - 15 DETERMINATION OF PROOF STRESSES (Rp , Rt)
16 - 15.1 General
16 - 15.2 Proof stress (non-proportional elongation) (Rp )
16 - 15.3 Proof stress (total elongation) (Rt)
16 - 15.4 Alternative values
16 - 16 DETERMINATION OF PERMANENT SET STRESS (Rr)
17 - 17 PROVING TEST FOR PERMANENT SET STRESS
17 - 18 DETERMINATION OF TENSILE STRENGTH (Rmm)
17 - 19 DETERMINATION OF PERCENTAGE ELONGATION AFTER FRACTURE (A)
17 - 19.1 General
17 - 19.2 Use of conversion equation
17 - 19.3 Fractures outside the central zone
17 - 20 DETERMINATION OF PERCENTAGE REDUCTION OF AREA (Z)
17 - 20.1 General
18 - 21 RECORD OF RESULTS
18 - 22 TEST REPORT
19 - APPENDIX A - PURCHASING GUIDELINES
19 - A1 GENERAL
19 - A2 INFORMATION TO BE SUPPLIED BY THE PURCHASER
20 - APPENDIX B - NOTES ON THE DETERMINATION OF YIELD STRESSES AND PROOF STRESSES
20 - B1 OBSERVATIONS ON FORCE-EXTENSION DIAGRAMS
22 - B2 UPPER AND LOWER YIELD STRESSES
22 - B3 NON-PROPORTIONAL AND TOTAL ELONGATION PROOF STRESSES
22 - B4 COLD-STRAIGHTENED TEST PIECES
22 - B5 SLOPE OF ELASTIC SECTION OF CURVE
24 - APPENDIX C - NOTES ON STRAIN RATE CONTROL FOR THE DETERMINATION OF YIELD STRESS, PROOF STRESS AND PERMANENT SET STRESS
24 - C1 GENERAL
24 - C2 MEASUREMENT OF STRAIN RATE
24 - C3 MACHINE AND TEST PIECE BEHAVIOUR DURING TEST
25 - C4 STRAIN RATE CATEGORIES
26 - C5 METHODS OF CONTROL OF STRAIN RATE
26 - C5.1 By servo control
26 - C5.2 By the use of a strain rate meter
26 - C5.3 By control of grip separation rate
26 - C6 CALIBRATION OF EQUIPMENT USED TO PERFORM TESTING AT HIGH SUPPLEMENTARY STRAIN RATES
26 - C6.1 The force measuring system
26 - C6.2 Extensometer
27 - C7 DISCONTINUOUS YIELDING
27 - C8 STORED ENERGY AND ENERGY RELEASE AT YIELD
28 - APPENDIX D - ERRORS DUE TO THE USE OF SIMPLIFIED EQUATIONS IN THE DETERMINATION OF CROSS-SECTIONAL AREA OF LONGITUDINAL TUBE
29 - APPENDIX E - GUIDANCE ON DETERMINATION OF PERCENTAGE ELONGATION AFTER FRACTURE
29 - E1 MARKING OF GAUGE LENGTHS
29 - E2 MEASUREMENT
29 - E3 SURFACE FINISH
30 - APPENDIX F - GUIDANCE FOR PRODUCT STANDARDS DRAFTING COMMITTEES

Sets out requirements for test pieces and specifies methods for the uni-axial tensile testing of metals at room temperature to determine tensile strength, yield, proof and permanent set stresses and percentage elongation and reduction of area. It specifies a standard strain rate but allows the use of four supplementary strain rate categories for special test applications.

This Standard sets out methods by which a test piece of metal is strained in uni-axial tension at room temperature in order to determine one or more of its tensile properties. It defines the properties to be determined and the terms used in describing tests and test pieces. The Standard also specifies the dimensions of standard test pieces and methods for tensile testing a wide range of product forms. This Standard does not cover through thickness tensile tests, tensile tests at elevated temperature (see AS 2291), the determination of uniform elongation (see AS 2346), or the measurement of plastic strain ratio (see AS 2403).NOTES:1 The properties which are to be determined and the criteria for assessment of the results of tests are not included; they should be set out in the relevant product Standard.2 Advice and recommendations on information to be supplied by the purchaser at the time of enquiry and order for the testing to be performed are contained in Appendix A.

First published as AS A23-1928 (being endorsement of BS 18-1910 without amendment).
Second edition 1960 (being endorsement of BS 18-1956 subject to Australian amendment).
Third edition 1964 (being endorsement of BS 18-1962 subject to Australian amendment).
AS A23-1964 revised and redesignated AS 1391-1974.
Second edition 1991.