| dc.description.abstract | The main purpose of this experiment is to compare the mechanical properties of hydrogen
charged and uncharged samples. This thesis work started with the machining samples of AISI
1074 rectangular bar into tensile test specimen. This whole process involved cutting,
machining, heat treatment, tempering and this results to 17 samples for tensile test. To obtain
this all the specimens were heated at 900 degree Celsius for 30 minutes and quenched into the
oil. Later on different samples were tempered at different temperature as per the selection. They
were split into 3 groups, where 2 groups were hydrogen charged with different time durations.
Vickers hardness test is used to measure hardness of different samples.
The next step is to induced hydrogen inside the samples for certain period of time by placing
into the electrolyte with distilled water 3.5 wt. % Nacl. The sample had each an incubation
period of between 14-20 days assuming sufficient hydrogen diffusion after 2 weeks. The
samples from group 2 and group 3 were hydrogen charged which is done by designing and
machining a canister to surround the specimen during testing where group 1 were tested in air
with normal strain rate. This samples underwent normal tensile test to determine the elastic
modulus, yield strength of the material. And the other group of rods were immersed inside the
3.5 wt. % NaCl and subjected to the cathodic protection, where titanium electrode were used
as counter electrode for the diffusion of hydrogen inside the sample. Results were compared
between all series shows clear indication of hydrogen embrittlement in group 2 and group 3. | |
