Trouser tear test specimens, approximately 24 mm
wide, 30 mm long and 1.8 mm thick with each leg being
approximately 12 mm wide and 15 mm long, were
prepared from compression moulded sheets. Approximately
10 mm of the leg of the trouser was clamped in the
grip during testing. As the sample was cut from the sheet
using a razor blade, the initial crack tip would be unrealistically
sharp [4] when compared to a conventionally torn
crack surface. Therefore, prior to tear testing, a more
characteristic crack tip was introduced by performing some
small scale tearing using an in-house straining device.
In order to obtain a wide range of tearing rates, three
different types of test equipment were employed: a screwdriven
test machine; a pneumatic test rig and a dropweight
test rig (Fig. 3). The experimental details are
similar to those described by Sakulkaew et al. [7]. In addition,
for the relatively low test speed approximately
between 8.3 106 m/s and 0.04 m/s, a temperature test
chamber (Instron 3119-005 Temperature Chamber) was
employed with the screw-driven machine. For the relatively
high speed test that is beyond the limit provided by
the screw-driven machine, an in-house temperature
chamber made of aluminium tube with an inside diameter
of 100 mm wrapped with a silicone rubber heating
element, and with a microprocessor-based temperature
controller (Watlow Series 965), was built to help characterise
the rapid tear behaviour at elevated temperatures.
The schematic diagram for the in-house test chamber fitted
with the pneumatic test rig is shown in Fig. 3.
Trouser tear test specimens, approximately 24 mmwide, 30 mm long and 1.8 mm thick with each leg beingapproximately 12 mm wide and 15 mm long, wereprepared from compression moulded sheets. Approximately10 mm of the leg of the trouser was clamped in thegrip during testing. As the sample was cut from the sheetusing a razor blade, the initial crack tip would be unrealisticallysharp [4] when compared to a conventionally torncrack surface. Therefore, prior to tear testing, a morecharacteristic crack tip was introduced by performing somesmall scale tearing using an in-house straining device.In order to obtain a wide range of tearing rates, threedifferent types of test equipment were employed: a screwdriventest machine; a pneumatic test rig and a dropweighttest rig (Fig. 3). The experimental details aresimilar to those described by Sakulkaew et al. [7]. In addition,for the relatively low test speed approximatelybetween 8.3 106 m/s and 0.04 m/s, a temperature testchamber (Instron 3119-005 Temperature Chamber) wasemployed with the screw-driven machine. For the relativelyhigh speed test that is beyond the limit provided bythe screw-driven machine, an in-house temperaturechamber made of aluminium tube with an inside diameterof 100 mm wrapped with a silicone rubber heatingelement, and with a microprocessor-based temperaturecontroller (Watlow Series 965), was built to help characterisethe rapid tear behaviour at elevated temperatures.The schematic diagram for the in-house test chamber fitted
with the pneumatic test rig is shown in Fig. 3.
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