Page 115 - Template Tesis UTM v2.0

Low-velocity impact test was carried out according to ASTM D7136-12 [133],

by using the instrumented drop weight impact test, Instron-Ceast 9350 as shown in
Figure 3.9. The specimens were cut with a dimension of 100 mm x 100 mm and

clamped circumferentially along a diameter of 75 mm. Prior to the test, specimens
were automatically clamped, then impacted with an indentor identical to the one used

in the quasi-static indentation test. To prevent the specimen from having multiple
impacts, the tup was caught on the rebound by a brake in the test apparatus. Damage

was imparted through out-of-plane, concentrated impact (perpendicular to the plane of

the laminated plate) and the damage resistance was calculated in terms of size and type
of failure mode exhibited in the specimens. In general, the damage resistance

properties generated are highly dependent on several factors, including specimen
geometry, lay-up, impactor geometry, impactor mass, impact force, impact energy,

and boundary conditions [133]. The contact force history of the specimens was
obtained from the instrumented tup and the data was measured by a high-speed data

acquisition device (DAS 64K) with a sampling rate of 100 kHz. At least three impact

tests were performed for each sample to obtain the average data. The impact energy is
calculated based on the following recommendations as shown in Equation 3.6 [133];

x 2
= (3.6)

2

Where ;

- impact energy (J)

- mass of impactor (kg)

- impact velocity (m/s)

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