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One tensile test piece, transverse to the direction of rolling shall be taken from each lot of 25 tonnes of material or part thereof from each cast rolled or processed at the same time. In case of coils, one tensile test piece shall be taken from each coil.

1.1.1 When plate, sheets and strips of more than one thickness are rolled from the same cast, one additional tensile test shall be made for each thickness

1.2 Tensile Test

The tensile test shall be carried out in accordance with IS 1608, generally using a proportional gauge length Lo = 5.65 √S_o, where S_o is the cross sectional area of the test piece. The pieces with a non-proportional gauge length may be used; in this case the elongation values shall be converted in accordance with IS 3803 :Part I. The tensile strength, yield stress and percentage elongation shall be as given in Table 1.

Tensile Strength MP_a	Yield Stress Mpa, Min.	Percent Elongation at Gauge Length 5.65 √S_o	Internal Diameter of Bend
(1)	(2)	(3)	(4)
350 - 450	240	25	t
where t is the thickness of test piece.

1.2.1 Should a test piece break outside the middle half of its gauge length and the percentage elongation obtained is less than that specified, the test may be discarded at the option of the manufacturer and another test made from the sample selected representing the same cast and batch.

2 Bend Test

2.1 Number of Bend Tests

One bend test piece shall be taken from each lot of 10 tonnes of material or part thereof from each cast and processed at the same time. In case of coils, one bend test piece shall be taken from each coil.

2.1.1 When plates, sheets and strips of more than one thickness are rolled from the same cast, one additional bend test shall be made for each thickness.

2.2 Bend Test

Bend test shall be carried out in accordance with IS 1599.

2.2.1 Bend test piece shall be cut so that the axis of the bend is parallel to the direction of rolling, that is, the longer axis of the test piece shall be at 90° to the direction of rolling.

2.2.2 The test piece shall be bend cold through 180°. The internal diameter of the bend for material shall be as given in Table-3. The test piece shall be deemed to have passed the test if the outer convex surface is free from cracks after complete bending.

2.2.3 It is some times difficult to ensure that the material is accurately following the radius. In case of dispute, the test piece may be pushed into a block of lead by a former of appropriate diameter.

3 Strainage Embrittlement Test

3.1 The plates, sheets and strips shall pass the strain age embitterment test as outlined in 9.1.2 to 9.1.5.

3.1.1 One strain age embitterment test shall be taken from each heat / cast.

3.1.2 The test piece, 75mm long and 25 mm wide, shall be so cut that the longer axis is at right to the direction of rolling. The edges of the test piece may be rounded and smoothed longitudinally to an approximately semicircular counter.

3.1.3 The test piece shall be bent cold through 90° round former having its diameter equal to three times its thickness. The axis of the bend shall be parallel to the direction of rolling.

3.1.4 The test piece shall then be heated at 250 ±5°C and maintained at that temperature for 15-minutes and then cooled in still air to room temperature.

3.1.5 The test piece shall when straightened by hammer blows on the apex of the bend, flatten without cracking.

4 Erichsen Cupping Test

4.1 Cupping test shall be carried out for sheets and strips material having a nominal thickness up to and including 3.15 mm. The test shall be carried out in accordance with IS 10175 Part I for thickness up to and including 2.0 mm and in accordance with the method given in Annex A for thickness above 2.0 mm.

4.2 One cupping test shall be carried out from each lot of 10 tonnes of material or a part thereof from each cast. In case of coils, one cupping test shall be carried out on each coil.

4.3 The surface of the cup shall be smooth and fracture shall not exhibit any undue directionality. The maximum cup depth shall be 13.5 mm minimum for actual sheet thickness range of 2.80 to 3.20 mm. For sheets/strips of other thicknesses, the minimum cup depth shall be mutually agreed upon.

5 Retest

Should any one of the test piece, first selected, fail to pass any of the tests specified in this standard, two further samples shall be selected from the same lot for testing in respect of each failure. Should the test pieces from both these additional samples pass, the material represented by the test sample shall be deemed to comply with the requirement of that particular test.

Should the test pieces from either of these additional samples fail, the material represented by the test sample shall be deemed as not conforming to this standard.

6 Freedom from Defects

The finished material shall be free from harmful defects such as seams, pipe, laminations, cracks, silvers, rolled-in-scale, blisters and pitted surface which will impair the drawability.

7 Dimensions and Tolerances

7.1 Unless agreed otherwise, dimensions of steel plate, sheet and strip shall conform to the dimensions specified in IS 1730.

7.2 Tolerances on length, width, thickness and mass of the steel plate, sheet and strip shall conform to the tolerances specified in IS 1852.

8 Condition of Delivery

8.1 The material may be supplied in hot rolled and normalized or hot rolled under controlled conditions.

8.2 Subject to prior agreement between the manufacturer and the purchaser the material may be pickled and leveled with a suitable protective treatment in accordance with IS 13566.