ISO 6603-2:2000 pdf download

ISO 6603-2:2000 pdf download.Plastics- Determination of puncture impact behaviour of rigid plastics Part 2: Instrumented impact testing.
4 Principle
The test specimen is punctured at its centre using a lubricated striker, perpendicularly to the test-soecimen surface and at a nominally uniform velocity. The resulting force-deflection or force-time diagram is recorded electronically. The test specimen may be clamped in position during the test.
The force-deflection diagram obtained in these tests records the impact behaviour of the specimen from which several features of the behaviour of the material may be inferred.
5 Apparatus
5.1 Testing device, consisting of the following essentiai components:
energy carrier, which may be inertial-mass type or hydraulic type (see 5.1 .1); striker, which shall be lubricated;
specimen support with a recommended clamping device.
The test device shall permit the test specimen to be punctured at its centre, perpenaicuiar TO its surtac at a nominally constant velocity. The force exertec on the test specimen in the direction of impact and the deflection from the centre of the test specimen in the direction of impact shall be derivable or measurable (see Figure 5).
5.1.1 Energy carrier, with a preferred impact velocity of (4.4: 0.2) rn/s (see 3.1 and note to 3.1). To avoid results, which cannot be compared due to the viscoelastic behaviour of the material under impact, the decrease of velocity during the test shall not be greater than 20 O
NOTE For brittle materials, an impact velocity of I m. s may be found to be more appropriate because it reduces the level of vibration and noise and improves the quality of the force-deflection diagram (see annex Aj
5.1.1.1 Hydraulic type. consisting of a high-speed testing machine witri suitable attachments.
NOTE In many cases, a weighted energy carrier with a total mass m of 20 kg has been found to be sufficient for the larger striker and of 5 kg for the smaller striker (see 5.1.2).
5.1.2 Striker, preferably having a polished hemfspherical striking surface of diameter (20.0 – 0,2) mm.
Alternatively, a (10 ± 0,1) mm diameter striking surface may be used.
NOTE 1 The size arid dimensions of the striker and condition of the surface w11 affect the impact results.
The striker shall be made of any material with sufficient resistance to wear and of sufficiently high strength to prevent plastic deformation. 19 practice, hardened steel or materials with lower density (i.e. titanium) have been found acceptable.
The hemispherical surface of the striker shall be lubricated to reduce any friction between the striker and the test wecimen (see note 2 and annex B).
NOTE 2 Test results obtained with a lubricated or dry striker are likely to be different. Below ambient temperatures. condensation can act as a lubricant.
The load cell shall be located within one striker diameter from the tip of the striker, i.e. mounted as closely as possible to me tip to minimize all extraneous forces and sufficiently near to fulfil the frequency-response requirement (see 5.2). An example is shown in Figure 5.
5.1.3 Support ring (see Figures 5 and 6), placed on a rigid base and designed such that air can not be trapped under the test specimen, thus avoiding a possible spring effect. Below the support ring, there shall be sufficient space for the striker to travel after total penetration of the test specimen. The recommended inside diameter of the support ring is (40 2) mm, or alternatively (100 z 5) mm, with a minimum height of 12 mm.
5.1.4 Base for test device, firmly mounted to a rigid structure so that the mass of the base see Figure 5) is of sufficient stiffness to minimize deflection of the specimen support.
When calculating the deflection from the kinetics of the accelerated mass, a minimum mass ratio m/in of 10 between base (me) and energy carrier (‘c) shall be used. This prevents the base from being accelerated by more than 1 °‘ of the impact speed up to the end of the tes:. For directly measured defiections, this minimum ratio is a recommendation only. For the principles of this specificatior see annex B of ISO 179-2:1997.
5.2 Instruments for measuring force and deflection:
5.2.1 Force measurement system, for measuring the force exerted on the test specimen. The striker may beequipped with strain gauges or a piezoelectric load transducer which shal be placed close to the striker tip. Anyother suitable method of force measurement is also acceptable. The measuring system shall be able to recordforces with an accuracy equal to or within 1 % of the relevant peak force.
The force measurement system shall be calibrated as set-up ready for measurement.Calibration may beperformed statically (for example,by imposing known loads on the striker) or dynamically (see for examplereference [4]).Errors in force measurement after calibration shall be less than = 0.5 % of the forces used forcalibration.
As the duration of the test is very short, only electronic load cells with a high natural frequency shall be used (seenote 1). The natural frequency f, of the test device (striker and load cell） shall conform to the folilowing condition.