Experimental and numerical investigation of plain and Ni-reinforced porous alumina ceramics composites produced with agro-waste pore formers
The mechanical and corrosion resistance properties of porous alumina ceramics are of utmost importance in understanding their operational behavior if they are to stand the test of time. Recently, porous alumina systems have been considered suitable for application in wide-ranging industrial pr...
Saved in:
| Main Author: | |
|---|---|
| Format: | Thesis |
| Language: | English |
| Published: |
2018
|
| Subjects: | |
| Online Access: | http://psasir.upm.edu.my/id/eprint/75672/1/FK%202018%20135%20-%20IR.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | The mechanical and corrosion resistance properties of porous alumina ceramics are
of utmost importance in understanding their operational behavior if they are to stand
the test of time. Recently, porous alumina systems have been considered suitable for
application in wide-ranging industrial processes that require extreme service
conditions such as high temperatures and corrosive mediums due to their satisfactory
thermal, mechanical and corrosion resistance properties. However, due to the
inherent brittleness of ceramics and their high sensitivity to thermo-mechanical
loading, large-scale production of porous alumina components for the above
applications is constrained. In the present study, the singular effect of different pore
formers (rice husk and sugarcane bagasse) as well as the joint effect of these pore
formers and nickel (Ni) reinforcement on the mechanical and corrosion resistance of
plain and Ni-reinforced porous alumina ceramics composites have been studied
respectively. Experimental results showed that the mechanical properties of the plain
porous alumina ceramics decreased with rising pore former content (hardness, tensile
stress and compressive stress of 529.1-26HV, 20.4-1.5MPa and 179.5-10.9MPa
respectively). Moreover, higher mechanical properties were observed in the SCBgraded
samples up to the 15wt% PFA mark, while beyond this point, the silica peak
present in the RH-graded samples favored their relatively higher value. The corrosion
resistance evaluation of the plain porous alumina ceramics showed that the RH and
SCB graded samples demonstrated superior corrosion resistance in strong acid and
strong alkali mediums respectively. For the Ni-reinforced porous alumina
composites, an inverse relationship was established between the mechanical
properties and Ni reinforcement. Overall, maximum hardness, tensile stress and
compressive stress values of 167.3HV, 12.6MPa and 55.3MPa respectively were
exhibited by the RH-graded porous alumina composite reinforced with 2wt% Ni.
Relative to the plain porous alumina series, the RH-graded composites exhibited a
better corrosion resistance in the corrosive mediums as compared with the SCBgraded
counterparts which demonstrated reduced performance in both mediums.
Moreover, superior corrosion resistance was observed in the RH-graded porous alumina composite reinforced with 2wt% Ni. The Levenberg Marquardt Back
Propagation Artificial Neural Network (LMBP ANN) was deployed as an artificial
intelligence model to characterize the plain and Ni-reinforced porous alumina
ceramics composites developed in the present study. The inputs of the models
developed include the sample formulation and the corroding time while the outputs
are the density, porosity, hardness, compressive stress, tensile stress, tensile modulus,
mass loss in NaOH and mass loss in H2SO4. The accuracy and performance efficiency
of the developed models (ANN I and ANN II) were confirmed by the large coefficient
of determinant (≥ 0.95) registered for the plots of all the experimental results against
their corresponding LMBP ANN predicted results. A Graphical User Interface was
designed to create a user friendly platform that provides users with real time
characterization of the plain and Ni-reinforced porous alumina ceramics composites. |
|---|