Author(s): Muhammad Sardar
Mentor(s): Shaghayegh Bagheri, Department of Mechanical Engineering
AbstractNumerous studies in the field have commonly relied on a singular mixing method for composite formulation, without delving into the comparison of various mixing techniques. Consequently, the primary objective of this research is to identify the most optimal manufacturing process for formulating FDM printed PLA/HA composite structures, achieved through a comprehensive comparison of four distinct mixing methods. These methods include the utilization of a magnetic stirrer, and speed mixer, which will be systematically examined for fabricating PLA/HA material. In order to arrive at a sound conclusion, this study will conduct thorough mechanical and tribological characterizations of the FDM printed PLA/HA structures, aiming to ascertain the best methodology for fabricating PLA infused with 3% wt of HA. By presenting these findings, this research aims to contribute significantly to the collective knowledge surrounding FDM printing and the formulation of PLA-based composites. The data obtained will offer valuable insights for the advancement of this innovative field.
Audio TranscriptHello everyone and welcome to my project on mechanical and surface characterization of PLA/HA composites.
The main objective of this research is to find an optimal manufacturing method for PLA/HA composite, based on the comparison of three mixing methods. We have seen that previous studies have only focused on the weight percent of Hydroxyapatite in the PLA samples, but no studies have been found yet to focus on the manufacturing method and how it affects the mechanical characterization and surface area of the sample. So, for that purpose, we have proposed three manufacturing methods that includes magnetic stirring, dry speed mix and wet speed mix.
Now, the dry and wet speed mix are not that different, except, the wet speed uses an organic compound called dichloromethane or DCM, which exists in a liquid state at room temperature. Once the material is ready, it is then used for filament extrusion.
This is machine, called extruder where the raw material is fed into which melts these pellets at about 210 Celsius and we can see the filament is coming out on the other side. This filament is then inserted into a 3D printer to print the sample.
This is the next step called indentation, where the machine applies and gradually increases the load to access the hardness and elasticity of the sample. This step is then later on key to analyze the tribology and surface properties of the sample.
From Electron Microscope images, we can see the indentation that was done on the surface with a closer view on the right side.
Apart from the SEM images, we have also done something called EDS, or electron dispersive spectroscopy. Basically, what it does is the electron beam in the electron microscope emits high energy electromagnetic waves, or x-rays, on the surface of sample which results in ejection of innermost electrons and hence, we can see what the chemical composition of the sample is.
As expected, we have seen an abundance of carbon followed by oxygen and phosphorus. The gold is only present because the sample was gold coated before doing EDS to prevent it from burning. All the colored areas indicate the presence of their respective element, and we are also given a spectrum as to the percentage of each element is present.
I think it is important to mention here about the limitation of our Scanning Electron Microscope as it cannot detect hydrogen. We have seen some cases where the percent composition is not adding up to 100% so it‘s probably most likely that this is hydrogen unless we know that our sample does not have any trace amount of hydrogen in it.
PLA/HA composites have plethora applications in the real world from aerospace to modern medicine to especially in bioengineering where it is used in bone fracture repair, which is the motivation of our research.
Now this concludes my video and if you have any questions about my research, don‘t forget to comment down below and I will reach out to you as soon as possible. Thank you very much!
The main objective of this research is to find an optimal manufacturing method for PLA/HA composite, based on the comparison of three mixing methods. We have seen that previous studies have only focused on the weight percent of Hydroxyapatite in the PLA samples, but no studies have been found yet to focus on the manufacturing method and how it affects the mechanical characterization and surface area of the sample. So, for that purpose, we have proposed three manufacturing methods that includes magnetic stirring, dry speed mix and wet speed mix.
Now, the dry and wet speed mix are not that different, except, the wet speed uses an organic compound called dichloromethane or DCM, which exists in a liquid state at room temperature. Once the material is ready, it is then used for filament extrusion.
This is machine, called extruder where the raw material is fed into which melts these pellets at about 210 Celsius and we can see the filament is coming out on the other side. This filament is then inserted into a 3D printer to print the sample.
This is the next step called indentation, where the machine applies and gradually increases the load to access the hardness and elasticity of the sample. This step is then later on key to analyze the tribology and surface properties of the sample.
From Electron Microscope images, we can see the indentation that was done on the surface with a closer view on the right side.
Apart from the SEM images, we have also done something called EDS, or electron dispersive spectroscopy. Basically, what it does is the electron beam in the electron microscope emits high energy electromagnetic waves, or x-rays, on the surface of sample which results in ejection of innermost electrons and hence, we can see what the chemical composition of the sample is.
As expected, we have seen an abundance of carbon followed by oxygen and phosphorus. The gold is only present because the sample was gold coated before doing EDS to prevent it from burning. All the colored areas indicate the presence of their respective element, and we are also given a spectrum as to the percentage of each element is present.
I think it is important to mention here about the limitation of our Scanning Electron Microscope as it cannot detect hydrogen. We have seen some cases where the percent composition is not adding up to 100% so it‘s probably most likely that this is hydrogen unless we know that our sample does not have any trace amount of hydrogen in it.
PLA/HA composites have plethora applications in the real world from aerospace to modern medicine to especially in bioengineering where it is used in bone fracture repair, which is the motivation of our research.
Now this concludes my video and if you have any questions about my research, don‘t forget to comment down below and I will reach out to you as soon as possible. Thank you very much!