BS ISO 10113 pdf download – Metallic materials一 Sheet and strip 一 Determination of plastic strain ratio

BS ISO 10113 pdf download – Metallic materials一 Sheet and strip 一 Determination of plastic strain ratio.
5 Principle
A test piece is subjected to a tensile test to a specified plastic strain level and the plastic strain ratio. r, is calculated from measurements of the changes in length and width. The orientation of the test piece relative to the rolling direction, and the plastic strain level for which the values of rare determined, are as specified in me relevant product standard, As a rule, the strain level shalt be lower man the plastic extension at maximum force.
6 Test equIpment
The tensile testing machine used shall comply with the requirements of ISO 6892.
For the manual method, the device for the measurement of the changes In gauge length shall be capable of rneasunng to within ± 0,01 mm, The device used for determining the changes in gauge width shall be capable of measunng to within t 0.005 mm.
For the automatic method (see Clause 8), extensomelers defined In ISO 9513:1999. of class 1 or better, shall be used.
NOTE When a long gauge length and large elongation are applied, the maximum relative error of the class I extensometer may be greater than a 001 mm.
The method of gripping the test piece shall be as specified in ISO 6892.
7 Test piece
7.1 The test piece shall be taken In accoi’dance with the reqarements of the relevant prockict standard or, II not specified therein, as agreed between the interested parties.
The type of the test piece and its preparation, wicluding machining tolerances, the tolerances on shape and the marking of the original gauge length. shall be as defined in ISO 6892:1998. Annex A, but within the gauge length the edges shall be sufficiently parallel thai two width measurements do not dif let by more than 0,1 % of the mean of all the width measurements.
7,2 The test piece thickness shall be the full sheet thickness, unless otherwise specified.
7.3 The surface of the test piece shall not be damaged, e.g. by scratches.
8 Procedure
8.1 In general, tests are camed out at an.ent temperature between 10 C and 35 C. Tests carried out under controlled conditions, where required. shall be made at a temperature 01(23 ± 5) C.
8.2 If the measurements are made manually, the original width of the test piece shall be measured at a minimum of three points evenly distributed along the gauge length, including one measurement at each end at the gauge length. The mean value of these width measurements shall be used in calculating the plastic strain ratio.
8.3 If the measurements are made automatically, the extension and the change of width, at least at one measurement point, shall be measured using an extensornefer, as specified in Clause 6.
8.4 In the plastic range. the strain rate of the parallel length shall not exceed 0,008/s.
For an explanation, see Figure 2.
If the automatic method is used, in Equations (5) and (7) L0 should be replaced by Le.
From a strictly physical standpoint, in Equations (5), (6) and (7) the true cross-sectional area S according to Equation (8) should be used instead of the original cross-sectional area S0, to calculate the true plastic length strain t . the true plastic width strain c b and the plastic strain e. Practice has proved that the results obtained with S0 or S are not significantly different. Hence, the original cross-sectional area S0 should be used in Equations (5), (6) and (7).