FulanoDetailStabilization in the Oven: The spun lignin fibers are then stretched and heated in an oven at around 300°C for 20 to 30 hours in a nitrogen-purged chamber. This step is referred to as stabilization and is crucial for aligning the molecular chains within the fibers. Stretching the fibers in a controlled manner at elevated temperatures under an inert atmosphere (to prevent oxidation) leads to an ordered structure that will later facilitate graphitization.
Carbonization: Once stabilized, the fibers are subjected to a carbonization process. The stabilized fibers are heated to temperatures ranging from 500°C to 1000°C for around 10 minutes in a nitrogen-purged chamber. During this step, the organic components of the lignin fibers decompose, leaving behind carbon structures. The key goal here is to eliminate non-carbon elements (such as hydrogen and oxygen), leaving a highly pure carbon fiber. The use of nitrogen prevents oxidation, which could damage the fibers during heating.
Final Fiber Properties: After the carbonization process, the resulting fibers have good mechanical properties, including high tensile strength and modulus, depending on the specific temperatures and processing conditions used.”
Although this is an astronomically easier way of making carbon fiber compared to the traditional method, I’m a little bit hesitant.
The wood welding like plastic may or may not work, and this method may or may not be practical in a DIY setup…
I say this because I can’t find pure lignin to buy online…
Observation:
I also found out that pitch/bitumen/asphalt/tar can be converted into carbon fiber, which has a tensile strength similar to the lignin-based carbon fiber.
The process of converting pitch resin into carbon fiber is similar to that of conventional carbon fiber (1 to 3 GPa of tensile strength).
Pitch/asphalt/tar/bitumen may be cheaper than buying pure lignin, but it is still more expensive than simply making stuff out of scrap (which is “free”).
The recent progress in pitch derived carbon fibers applications. A Review - ScienceDirect
I just found this method, but I’m not very sure how it is supposed to work.
The article explains it in a very general way and doesn’t tell what was the tensile strength achieved by each bio-precursor nor the specifics.
This paper explains how to make Activated Carbon Fibers from natural precursors. It is essentially done just the same way as the previous natural-based carbon fibers.
“Jute fiber contains lignin and cellulose in considerably higher proportions, which are essential ingredients for creating carbon fiber. Jute fibers are made up of 8% fibrils, 13.6–20.4% hemicellulose, and 67%–75% cellulose. Jute fiber is used a lot because it is one of the least expensive cellulose-based natural fibers and has a high Young's modulus in comparison to other natural fibers [41]. The precursor fiber is typically oxidised in the air; activated carbon fiber is created through carbonization in an inert environment followed by carbon dioxide activation. The oxidation is performed between 200 °C and 300 °C to prevent degradation or melting during the high heat treatment of the carbonization stage. Fig. 2 Schematic representation for the preparation of ACs from jute. The carbonization process occurs at high temperatures between 500 °C and 1000 °C in an inert atmosphere (typically nitrogen). The physical, chemical, and morphological properties of cellulose-based carbon fibers are greatly influenced by pre-treatment and the heat-treatment condition [49].”
You can use Jute, banana peels, coir, flax, maize, sisal, wood, bagasse, rice husk and others.
The paper also lists another method using chemical and heat treatment with Sodium Hydroxide, Zinc Chloride and Potassium Hydroxide.
Like I said, the paper doesn’t focus on the specifics, and in order to find how each type of fiber needs to be pre-treated and processed is only explained in the articles in the references.
Lignin Extraction:
ChatGPT suggested these articles that talk about extracting pure lignin, but all of them are hard and somewhat dangerous. The Organosolv process is one of them, although using cheap solvents (like ethanol) to extract lignin from wood pulp, it needs a pressure chamber of 30 bars of pressure at high temperatures to work.
This article claims to have found a method of doing it at room pressure:
I can’t access the first paper, but the second says the following:
“2.2.3 Alkaline glycerol organosolv treatment This procedure was modified from Guragain et al. [39]. Twenty grams of dry wood sawdust was mixed with 200 mL of glycerol solution in a round bottom glass flask. As a catalyst, 0.8 g NaOH was added into the mixture. The mixture was continuously stirred under reflux at 170 °C for 2 h. At the end of the treatment, the mixture was immediately filtered. The pulp was washed, and the filtrate was diluted with cold deionized water to 1 L. The precipitated alkaline glycerol lignin (AGOL) was washed, filtered, and dried at atmospheric conditions.”
I searched and this is the easiest version of the method,and the article says that all of the methods presented were able to yield 10 to 45% (45% being the glycerol + sodium hydroxide method) of lignin from the initial 20 grams of sawdust.
I would need 20 liters of glycerol and 100 liters of water to extract around 1 kilogram of lignin.
I searched for papers that use other materials (like cellulose) instead of lignin as the carbon precursor, but every material needs a different treatment that is inaccessible to me.
Some use ionic fluids, complex (and dangerous) acids, complex machines etc etc etc.
… Guess that this whole section was useless after all…
HDPE to Dyneema:
… Or maybe not.
… Because I revisited the original article that talked about increasing the strength of UHMWPE by adding 1% PE wax, because I felt that it was too good to be true.
The Structural and Mechanical Properties of the UHMWPE Films Mixed with the PE-Wax - PMC
And I was indeed correct, because it is not as simple as “just” adding PE wax to HDPE.
The method:
“2.1. Materials
UHMWPE GUR 4120 with a molecular weight of 5 × 106 g/mol and polyethylene wax PLWN-3W with a molecular weight of 4 kg/mol were purchased from “Ticona GmbH” (Germany) and “INHIMTEK LLC” (Novokuibyshevsk, Russia) respectively. PE-wax is a high-quality, non-oxidized, non-polar, linear, low molecular weight polyethylene, produced according to the high-temperature destruction process. P-xylene with a ratio of 2.5 mL of a solvent per 1 g of the polymer blend was used as a plasticizer for the UHMWPE composites.
2.2. Fabrication of the Films
Mixing UHMWPE and PE-wax powders was done in a high-energy planetary ball mill APF-3 by using steel drums with a volume of 900 mL. The grinding media was steel balls (their diameter is in the range of 7–9.5 mm). In the mixing process, current water was used in order to cool down the drums and control the temperature of the blends at about 60 °C. The average rotation speed was 450 rpm. The total time for mixing was 90 min. The UHMWPE/PE-wax powders with various PE-wax contents (0.1, 0.2, 0.5, 1.0, 1.5, 2.0, 10.0, and 20.0 wt.%) were prepared.
Gel-spinning technology was applied to obtain the oriented UHMWPE films by using a small amount of the solvent as a plasticizer in accordance with the approach described in the reference [19]. The first step was mixing the UHMWPE/PE-wax powders and stirring them with p-xylene at 140 ± 2 °C for 20 min. The UHMWPE/p-xylene gel was extruded at a temperature of 150 ± 3 °C by using ram extruder UE-MSL (Extrusion Machinery Sales Ltd); after being stored for 15 min in the extruder at this temperature. The die size was 10 mm × 2 mm and the extrusion rate was equal to 500 mm/min. Then, the obtained gel was dried at room temperature for 2 days to obtain xerogel (solvent-free UHMWPE gel). The primary stage of the thermal orientation of xerogels was carried out by using rolling machine (BL-6175-A). Xerogels were rolled at 110 °C to reach a draw ratio value of 1.5–2.0. In the next stage, a particular laboratory device was used to make the UHMWPE/PE-wax films pass through a bath of a silicone oil and to draw them (Figure 1). The oil temperature was stable within ± 0.1 °C precision. Multi-stages hot orientation process for the UHMWPE films was carried out stepwise at various temperature values ranging from 120 °C to 142 °C. In each stage of the thermal orientation process, each UHMWPE/PE-wax composite had a different range of a draw ratio value at different levels of temperature.”
Xylene is not hard to find, the problem is P-xylene. I found only one website where it is sold, and it costs 1000 reais per liter (around 200 dollars).
The other article about making a full Polyethylene based composite also needed expensive solvents to dissolve HDPE, UHMWPE and PE wax.
This is me from the future:
I thought that P-xylene was something very hard to find, but in actuality, “Xylene P.A” is the same as “P-xylene”.
You need to check the molecular formula of the xylene in question, it needs to be “C8H10” with or without “C6H4(CH3)2”.
And I just found a 5 liter gallon for around 150 reais (30 dollars).
Of course, it won’t be as pure as the one used in the articles, but at least it is accessible.
Although, it is toxic.
HOWEVER:
The articles talk about fiber fabrication, not solid object fabrication.
In essence, they use a method similar to the one used to make Dyneema fibers.
They partially or completely dissolve the Polyethylene polymers in a solvent, then they draw/stretch the solution while removing the solvent in order to organize the molecules like a linear chain.
At best, they make films of the material.
In the first article they did in fact make solid objects with it, but it only achieved a maximum tensile strength of 160 MPa.
HOWEVER², I was wondering about something:
Since melting the molecularly aligned fibers into a molten material would make the resulting material lose its molecular properties, but what about partially melting the fibers? Like in a 3D printer style?
For example, if you align these fibers in a unidirectional laminate and then use heat and pressure to fuse them together, like a film. Would that maintain the properties of the polymer?
You could still use graphene powder and glass fiber for maximum strength.
From ChatGPT (because Deepseek always have its servers completely full):
“Incorporating graphene into ultra-high molecular weight polyethylene (UHMWPE), the base polymer of Dyneema fibers, has been shown to enhance tensile strength and other mechanical properties. Studies have demonstrated that adding 1 wt% graphene oxide to UHMWPE can increase the tensile modulus from 864 MPa to 1236 MPa and the tensile strength from 12.6 MPa to 22.2 MPa.
Another study reported that incorporating 1 wt% graphene nanoplatelets into UHMWPE improved tensile strength from 45 MPa to 68 MPa.
These enhancements are attributed to the high mechanical properties of graphene and its ability to improve the crystallinity and molecular alignment of the polymer matrix. However, the effectiveness of graphene reinforcement depends on factors such as the type and amount of graphene used, dispersion quality, and processing methods.
While these studies indicate potential benefits, specific research on incorporating graphene during the drawing/stretching process of Dyneema fibers is limited. Further investigation is needed to determine the optimal conditions and potential advantages of this approach.”
It seems it is a common application of dyneema fibers, which means I will find enough information to confirm if it is viable or not. Although the use of highly toxic Xylene is already a downside…
(PDF) Design with Ultra Strong Polyethylene Fibers (it doesn’t go into specific numbers, but it seems like the tensile strength of GPas was maintained for pressed laminate objects)
High performance Dyneema% fiber laminate for impact resistance/ macro structural composites (the delamination strength was around 0.05 MPa in this specific article)
Understanding the Thickness Effect on the Tensile Strength Property of Dyneema®HB26 Laminates
From the above article: “Russell et al. [9] noted that the failure strength and strain to failure of the yarn is 20% and 30–50% greater than the failure strength and strain to failure of the laminate, respectively. They attributed these differences to the changes in the morphology of the fibres during the consolidation process.”
Temperature and Strain Rate Related Deformation Behavior of UHMWPE Fiber-Reinforced Composites (also in the 600 MPa to 800 MPa)
Effect of Hot-Pressing Process on Mechanical Properties of UHMWPE Fiber Non-Woven Fabrics
Determination of tensile strength of UHMWPE fiber-reinforced polymer composites
Soooooo… It seems that all the stuff I wrote about all other options seems like unnecessary bloat to the project log…
Or maybe not, right?
I don’t like the idea of working with xylene… But all processes have their own pros and cons…
Also, there are lacquer thinners for Polyethylene that are easily accessible and a little more safer. They may or may not be as good as the very specific Xylene I talked about.
… Sooooooooo… I need to find a new solution.
Solutions for Structure Material:
Again, I’m not an engineer and you do the building steps at your own risk.
Option 1:
Just make composites with 80% graphene per weight.
Essentially: F*ck it, we ball.
Most, if not all articles about graphene powder composites focus on making composites with maximum 8% graphene per weight, none of them explore the possibility of simply using a polymer/resin as matrix for graphene powder reinforcement filler.
They only use it as an additive to slightly increase the strength of materials.
Continuous and low-carbon production of biomass flash graphene | Nature Communications
You can use biochar for the flash graphene process, and in order to make biochar you need to take wood/grass/food and just heat it in a low temperature space.
It is just charcoal/vegetable coal. 😐
The good part is that the equipment to make flash graphene is the same that I can use to test wood welding.
Observation: Just now I took the volume of a human with around 265cm tall (which is the height of the mech) and I added to a weight, volume and density calculator, which gave around 400kg to 570kg.
So you can’t make it 100% solid.
Observation 2:
In previous project logs I talked about graphene fibers, but after thoroughly reading a lot of them, all the methods are extremely hard to do in a DIY setup or just don’t achieve a significant strength.
I found this patent that claims that its 90% graphene 10% polymer (or the reverse) can achieve 100 to 300 MPa of tensile strength, but it didn’t specify which polymer was used and which proportion of graphene to polymer resulted in 300 MPa.
KR101195490B1 - Graphene composite fiber and the method for preparing the fiber - Google Patents
Option 2:
Or you can use glass fiber + epoxy resin with 0.2% graphene per weight and you would get a predictable result around 600 MPa.
Fiberglass is really expensive, especially in bulk and woven in bidirectional layers.
I had a huge section just to check for the prices of fiberglass rolls and packages that are sold online, but I think it was useless. The idea is to make this mech from scratch.
The cheap ones are made out of random fibers in a mantle (they are kept together by styrene), and can cost around 600 reais (100 dollars) for around 40kg in total, the chopped fibers are even cheaper (for every 10 kilograms you pay 100 reais or 16 dollars). But they aren’t that stronger in any case.
The glass fiber yarn normally costs around 500 reais (100 dollars) for around 20kg, and you would need to knit the laminate cloths by hand. DIY Loom + Electric Spinning Wheel - Printed Tee From Scratch (even with 3D printed looming machines it can take a while) Arduino CNC Embroidery Machine Oluwaseyi Sosanya's 3D weaving machine
The better and stronger ones can easily cost just as much per kilogram, so it is not viable.
Maybe you could manufacture your own fiberglass by melting glass or glass matrix composites.
Or maybe not, the tensile strength of chopped fiberglass epoxy resin is normally around 60 to 160 MPa depending on a few factors.
Physical and Mechanical Characteristic of Chopped E-Glass Fiber Reinforced Epoxy Composites
You could add a few fiberglass rebars (that you can cheaply buy only) and/or fiberglass woven clothes and/or metal meshes to increase structural integrity while the bulk is maintained by the chopped fibers + graphene.
But if you want to go ahead with the idea:
Fiberglass: How It's Made and Its Many Uses
Fiberglass Manufacturing How Fiberglass Is Made
Mini Lesson 3: How are Glass Fibers Made?
THE CONVERSION OF GLASS INTO GLASS FIBRE
GPX Glass Processing Application – Fiber Bundle
And yes, you can make fiberglass from any kind of glass, but specific types of glass will result in specific types of fibers. Some stronger, others weaker.
ChatGPT said that during the recycling process you could add:
“Limestone (Calcium Carbonate), Magnesium Oxide, Calcium Oxide, Barium Oxide, Sodium Sulfate, Alumina (Aluminum Oxide), Titania (Titanium Dioxide, and adding fibers, such as basalt, silica, or even carbon fibers.”
I guess that you could just add a lot of ceramic powders
For the fiberglass processing:
“In the production of fiberglass, chemical sizing or coating plays a crucial role in enhancing the performance and durability of the fibers. The sizing formulation typically includes a variety of components designed to improve the fibers' compatibility with resin systems and protect them during processing. Here are the main components used in fiberglass sizing:
Key Components of Chemical Sizing/Coating
Water: Often used as a solvent in the sizing formulation.
Silane Coupling Agents: These are specifically used for glass and basalt fibers to promote adhesion between the fibers and the resin matrix. Silanes help to create a chemical bond that enhances the overall strength of the composite material.
Film Formers: These can be in dissolved, emulsified, or dispersed forms and are essential for creating a continuous film over the fibers, which aids in handling and processing.
Additives and Modifiers:
Surfactants: Help to improve the wetting properties of the sizing, ensuring better coverage of the fibers.
Plasticizers: Increase the flexibility of the sizing, making the fibers easier to handle.
Anti-static Agents: Reduce static electricity, which can cause fibers to clump together.
Antifoams: Minimize foam formation during the application of the sizing.
Rheology Modifiers: Adjust the flow properties of the sizing formulation to ensure even application on the fibers [1][2].
Importance of Sizing Sizing is critical for:
Protecting Fibers: It prevents damage during manufacturing processes such as weaving or winding.
Enhancing Compatibility: It improves the adhesion between the fiberglass and the resin, which is vital for the mechanical performance of the final composite product.
Providing Chemical Resistance: Sizing contributes to the chemical stability and thermal resistance of the fiberglass in various applications [2].
In summary, the chemical sizing/coating for fiberglass involves a complex formulation that includes silane coupling agents, film formers, and various additives to enhance the fibers' performance and compatibility with resins.”
Maybe after the production of the fibers, you could give them a salt bath in order to convert them into gorilla glass.
How to chemically strengthen glass (eg Gorilla Glass) I say MAYBE because the process can be really dangerous, Potassium Nitrate is explosive.
More useful links:
The Incredible Properties of Composite Materials
Carbon Fiber - The Material Of The Future?
Carbon Fibre Tubes - Everything You Need to Know
The Incredible Properties of Composite Materials
Easy Tricks Using Fiberglass Strengthening!
Composite Core Construction (In this one he uses phenolic microspheres, I couldn’t find it on my country [Brazil], but I do believe you can use any kind of microsphere as long it's made from a light-weight material and/or are hollow)
Home Made Micro Balloons - RC Groups
(I found these link that says that you can make DIY microspheres/microballoons or nanospheres/nanoballoons by grinding down styrofoam)
https://www.sciencedirect.com/science/article/abs/pii/S0167577X08009828
“Epoxy micro-balloons are prepared by dropping and stirring epoxy mixture in heated silicon oil. The mixture of epoxy, curing agent and blowing agent forms sphere particles, which are then blown via the function of blowing agent and simultaneously cured to form epoxy micro-balloons. “
“Glass microspheres can be made by heating tiny droplets of dissolved water glass in a process known as ultrasonic spray pyrolysis (USP), and properties can be improved somewhat by using a chemical treatment to remove some of the sodium. Sodium depletion has also allowed hollow glass microspheres to be used in chemically sensitive resin systems, such as long pot life epoxies or non-blown polyurethane composites.”
Making Infrared Cooling Paint From Grocery Store Items (w/Novel CaCO₃ Microsphere Synthesis) Although this video isn’t about structural composites, at 5:50 he explains that when packing spheres, the most efficient way of occupying as much space as possible is by mixing smaller spheres within the bigger spheres.
The issue is that I don’t know how many times the smaller spheres must be smaller than the bigger spheres.
I asked to ChatGPT:
“Experimental Evidence: Studies on binary sphere packings suggest that the optimal size ratio can vary based on specific conditions, but a ratio of about 1:3 to 1:4 (smaller to larger) is often cited as a good starting point for achieving efficient packing [2].”
From the link:
“Even if the large spheres are not in a close-packed arrangement, it is always possible to insert some smaller spheres of up to 0.29099 of the radius of the larger sphere.”
1 ÷ 3,436544211141 = 0.29099
By how much I talk about micro powders and all that stuff, I was thinking of buying microscopes to check the size of the fillers.
Do Cheap Microscopes Actually Work?
Laser Scanning Microscope from Blu-ray Player #3: Increasing the Resolution
You wont believe what you can see with this DIY Laser Microscope!
Super Strong Epoxy with Diamonds and More!
Observation:
You could replace the diamonds by zirconia, silicon carbide, alumina, boron carbide or moissanite.
Mouldless Carbon Fibre Technique for One-Off and Prototype Components
Resin Showdown: Epoxy vs Polyester Resin
HOW-TO CHOOSE THE BEST RESIN FOR YOUR NEXT PROJECT-DIY FIBERGLASS
HOW TO MAKE STRINGERS and TRANSOMS with PLYWOOD and EPOXY
Most Common Mistakes Working With Fiberglass!
Composite Materials : Vacuum vs Pressure
Understanding Honeycomb Panel and Honeycomb Composite Structures
HOW TO REPAIR FIBERGLASS DAMAGE WITH LIMITED ACCESS!
THINGS I WISH I KNEW AS A BEGINNER USING EPOXY FOR FIBERGLASS BOAT REPAIRS!
HOW-TO MAKE YOUR OWN EPOXY FILLERS and PUTTIES-DIY EPOXY FILLERS
HOW-TO MAKE FIBERGLASS and EPOXY SMOOTH and STRAIGHT-DIY EPOXY
Who Engineered the OceanGate Titan V2 Hull? Maybe Nobody Did?
OceanGate Titan Hull - Hundreds of Ill-advised Carbon Fiber Grind Spots
12 Weird Facts About Stockton's Titan Viewport
Also:
ChatGPT:
“Commercial two-part epoxy resin composites often undergo multi-curing and post-curing processes to enhance their mechanical and thermal properties. These processes can include methods such as dual curing, co-curing, and post-curing heat treatments.
Dual Curing: This technique involves applying multiple layers of resin, where each layer is partially cured using a specific curing method. Subsequent layers are added and cured in stages, allowing for overlapping curing phases. This staged approach promotes covalent bonding across layer interfaces, improving interlayer adhesion and overall structural integrity.
https://patents.google.com/patent/US20100272574A1/en?utm_source=chatgpt.com
Co-Curing: In co-curing, different resin systems are cured simultaneously, which can enhance interlayer bonding and streamline the manufacturing process. For example, combining phenolic and epoxy resins in a co-curing process has been shown to produce composites with favorable thermal and mechanical characteristics, making them suitable for aerospace and various industrial applications.
https://www.jkimst.org/journal/view.php?doi=10.9766%2FKIMST.2020.23.5.475&utm_source=chatgpt.com
Pre-Curing Procedures:
Proper Mixing: Accurately measuring and thoroughly mixing the resin and hardener are crucial. Mix the components for a full 2 to 3 minutes, ensuring to scrape the sides, corners, and bottom of the container to achieve a uniform mixture. This thorough mixing prevents improper curing and ensures optimal material properties.
Step-by Step Guide: Measuring and Mixing Epoxy Resins – Swell Composites
Controlled Pre-Curing: In certain applications, allowing the adhesive to undergo a controlled pre-curing phase can be beneficial. For instance, in automotive manufacturing, pre-curing two-component adhesives like epoxy can influence the deformation behavior of bonded joints. Shear tests on joints bonded under different pre-curing processes have shown that pre-curing time affects the strength and deformation characteristics of the adhesive. Therefore, optimizing pre-curing time is essential to achieve the desired mechanical properties in the final product.
During-Curing Procedures:
Temperature Control: Maintaining appropriate curing temperatures is vital. For room-temperature curing epoxies, an ideal range is 22 to 27 degrees Celsius with 20% relative humidity. Higher ambient temperatures can accelerate polymerization, while lower temperatures may slow the curing process.
Composite Fabricating Basics Step 4: Proper Curing
Vacuum Application: In processes like vacuum-assisted resin infusion, applying vacuum during curing helps remove air bubbles and excess resin, leading to a denser and more uniform composite structure. This technique is particularly useful when working with high-temperature curing epoxy resin systems.
https://www.talkcomposites.com/121/resin-infusion-process-using-high-temperature-curing-epoxy-resin?utm_source=chatgpt.com
Infrared Radiation Curing: Utilizing infrared radiation during curing can accelerate polymerization at low temperatures. Studies have shown that infrared curing can reduce the energy barrier of the epoxy/amine reaction, leading to faster curing times without the need for high temperatures. This method offers a cold and universal cure-on-demand process, which can be advantageous in various industrial applications.
Post-Curing Heat Treatments: After the initial curing, composites may undergo additional heat treatments to further polymerize the resin matrix. These post-cure heat treatments can increase the hardness, flexural strength, and fracture toughness of the composite. However, it's important to note that multiple post-cure cycles can alter thermal properties, potentially affecting physical and mechanical properties. Therefore, the number and conditions of post-cure cycles should be carefully controlled to avoid degradation of the resin matrix.
https://journals.sagepub.com/doi/abs/10.1177/00219983231169333?journalCode=jcma&utm_source=chatgpt.com
Implementing these curing processes appropriately can significantly enhance the performance and durability of epoxy resin composites in commercial applications.”
I intend on using glass trash to make the glass fibers in a continuous process, with tempering and chemical bath. Which would be safer, since I wouldn’t need liters and liters of potassium nitrate.
So, I was wondering about the best diameter for glass fiber composites, if the braiding was better than unidirectional fibers, how many fibers per strand is the best, etc.
An experimental study on mechanical properties of GFRP braid-pultruded composite rods In this one it only used a braided cover with a unidirectional fiber core, the purely unidirectional is obviously the strongest, but in only one direction. In the torsion tests, the braided rods surpassed the unidirectional strength by 3 times, and that is just the braided cover. Also, the flexibility of the structure is increased, which can be interesting for composites to avoid catastrophic failure and maintain a progressive, detectable failure.
(PDF) Optimisation of the fibre size for a Fiber Glass : Epoxy Composite
89 A STUDY ON E-GLASS FIBRE BRAIDED COMPOSITES274-280 (in this one the braiding only increased the mechanical properties slightly)
Can anybody explain the effect of orienting glass fibers 45 degrees in epoxy matrix? | ResearchGate
Relationship of Tensile Strength of Glass Fibers to Diameter (the thickness of the fibers also influenced the mechanical properties slightly)
Tensile strength and fracture surface characterisation of sized and unsized glass fibers
EFFECT OF SILANE TREATMENT OF E-GLASS ON THE CROSS-LINKING KINETICS OF AN EPOXY RESIN
ChatGPT:
“The choice between unidirectional, helical, or braided fiber configurations in fiberglass-epoxy composites significantly influences their mechanical properties and suitability for specific applications. Here's an overview of each configuration:
Unidirectional Fibers:
Description: Fibers are aligned in a single direction, providing maximum strength and stiffness along that axis.
Mechanical Properties: Composites exhibit high tensile strength and stiffness in the fiber direction but are weaker in transverse directions. This configuration is ideal for applications where loads are primarily applied along one axis.
Considerations: Manufacturing processes must ensure precise fiber alignment to achieve desired properties.
Helical Fibers:
Description: Fibers are wound in a helical pattern, typically at angles between 30° and 60° relative to the axis of the component.
Mechanical Properties: This arrangement enhances torsional strength and provides a balance between axial and hoop strengths. Helical composites are beneficial in applications requiring resistance to twisting forces.
Considerations: Manufacturing helical composites can be more complex and may require specialized equipment.
Braided Fibers:
Description: Fibers are interlaced in a braided pattern, typically at angles of ±45° or ±60° relative to the component axis.
Mechanical Properties: Braided composites offer excellent damage tolerance and resistance to delamination. They provide balanced strength and stiffness in multiple directions, making them suitable for complex load scenarios.
Considerations: Braided structures can be more challenging to manufacture and may require precise control to maintain fiber integrity.
Specific Numbers and Considerations:
Fiber Diameter: Individual fibers typically range from 3 to 20 micrometers (μm) in diameter. For optimal performance, a diameter range of 4 to 15 μm is preferred, with 5 to 10 μm being ideal.
Bundle Thickness: The overall thickness of the fiber bundle is preferably between 10 to 200 μm, with 30 to 150 μm being more favorable, and 50 to 120 μm considered optimal.
Manufacturing Considerations: The choice of fiber configuration should align with the intended application, desired mechanical properties, and manufacturing capabilities. Each configuration offers distinct advantages and challenges that must be balanced based on specific requirements.”
That is cool and all, but some of the sources the ChatGPT links in its answer doesn’t even mention the properties it claims to mention.
Also, when looking at fiber composites, I came across a question that I also couldn’t find the answer:
Which kind of composite is stronger:
Woven fabric rotated layers or unidirectional fiber rotated layers?
I ask this because I think it shouldn’t have a difference, since woven fabrics have each layer divided between 2 directions while unidirectional layers aren’t. But since you can wrap each layer in a different direction, then it wouldn’t make much of a difference on the final strength… Right?
If there isn’t much difference, then it would be easier to make composites with unidirectional layers. Just like those pressure vessels.
Superior energy absorption characteristics of additively-manufactured hollow-walled lattices
Design and Structural Optimization of Topological Interlocking Assemblies (Fabrication Result)
Sources: Design of architectured materials based on topological and geometrical interlocking - ScienceDirect (PDF) A novel non-planar interlocking element for tubular structures
Sources: New Approach to Road Construction in Oil-Producing Regions of Western Siberia A template design and automated parametric model for sustainable corbel dwellings with interlocking blocks
The principle of topological interlocking in extraterrestrial construction
https://www.researchgate.net/publication/228884549_Intricate_isohedral_tilings_of_3D_Euclidean_space
(PDF) Topological Interlocking Materials
https://arxiv.org/pdf/2405.01944
Topological Interlocking Assembly: Introduction to Computational Architecture
Design of Flat Vaults with Topological Interlocking Solids | Nexus Network Journal
(PDF) Response of reinforced mortar-less interlocking brick wall under seismic loading
Topological Interlocking as a Materials Design Concept
Design and Structural Optimization of Topological Interlocking Assemblies
(PDF) Interlocking Manifold Kinematically Constrained Multi-material Systems
In the end, isn't it better to just use a 3D chain structure with the 3D glass printer I showed above?
… Maybe a mix of both?
I also searched for glass powder reinforced composites, and none of them surpassed even 100 MPa of tensile strength, only half of it (50 MPa).
Tensile Tests of Glass Powder Reinforced Epoxy Composites: Pilot Study | Scientific.Net
Experimental investigation of glass powder reinforced polymer composite - ScienceDirect
Preparation and testing of glass powder reinforced polyester resin lamina - ScienceDirect
Maybe you can mix stainless steel and glass in a 30% to 70% glass ratio and reach a metal foam with a density of 2.7 g/cm³, which is similar to aluminum.
Well, the first problem with the idea is that neither metals nor glasses can be mixed together, called “immiscible”.
So you would need to either make an emulsion or a “bridge”, a material (or a series of materials) that bonds to both glass and metal. Metal alloys, such as steel, don’t have a chemical bond between carbon and iron, but carbon is dissolved into steel. So you would need a material that dissolves in both materials?
Melting Glass & Aluminum Together - ASMR Metal Melting - Bullet Casing Copper Casting - BigStackD
Mixing Glass and Steel using Sunlight non-conductive This video shows that it is very simple to make a mixture of it, but it also shows that the resulting material is extremely fragile…
The author of the video himself:
“Keep in mind I crushed this with a pair of pliers. Broken glass alone is much stronger, and also cannot be detected by a metal detector, also not conductive.”
I also had the idea of “just” melting or sintering alumina into parts, since it has 200 MPa of tensile strength.
But… It is not that simple…
What does sintering mean? Sintering process easily explained
Ceramic sintering at 1200°C using in situ ESEM microscopy
Ultrafast Hight-temperature sintering (UHS) for ceramics
Technology | Fused Aluminum Oxide Process | Imerys
Underwater laser cutting and silver sintering to make ceramic circuit boards
Melting Ceramic with an Acetylene Torch
Microwave Mishap - Silicon Carbide Sinter Experiment
Silicon Carbide Microwave Sinter Results
I don’t know where to post this, but:
Youtube’s algorithm suddenly suggested to me a video about growing crystals at home, so I wondered if it would be possible to grow a high strength crystal at home.
Growing Laser Crystals used in NUCLEAR FUSION!
The crystals that he grows are crystals that are used for lasers, prisms and piezoelectric devices. So they don’t have that much tensile strength, the one in the first video has around 3 MPa of tensile strength.
Most of the crystals that ChatGPT suggests are also in this range of strength.
For now, I can only find low strength crystals.
Anything stronger than this and google only shows extremely expensive, complex and dangerous processes for crystal growth.
How to Make a Real Diamond - (Not Clickbait)
How Are Lab-Grown Diamonds Made?
Making real diamonds from Scratch
Detonation synthesis: Watch how we make polycrystalline micron diamond!
HPHT and CVD Diamond Growth Processes | How Lab-Grown Diamonds are Made | GIA?
I finally found a little information on the subject, but I feel it is a similar rabbit hole of biofiber composites…
Description and effective parameters determination of the production process of fine-grained artificial stone from waste silica | Request PDF (tensile strength reached maximum 40 MPa, while compressive strength is around 100 MPa, but I guess that this is expected since there are essentially mineral stone)
While searching for different options I came across this article:
Source: New approach to prepare the highly pure ceramic precursor for the sapphire synthesis - ScienceDirect
1700ºC is basically half of the temperature required for sapphire/ruby synthesis.
On wikipedia it is said that one of the first synthetic sapphires were made using boric acid and alumina, but if it was that simple, we would be using that method.
“Growth by anhydrous dissolution
Created in 1847 by French chemist Jacques Joseph Ebelmen , this technique brings together in a platinum crucible the components of the desired synthetic gem, an important mineral called silica, a chemical coloring agent and an anhydrous flux (without water). Everything is heated under ambient pressure to the temperature of dissolution and recrystallization into single crystals. Slow rotation allows you to collect rubies, sapphires and emeralds”.
Synthetic laboratory gemstones Flamme en Rose
“In a platinum crucible, a flux consisting of litharge (mineral of PbO) and a small amount of boron oxide (B2O3) is used to dissolve the ruby (or sapphire) ingredients, Al2O3 and Cr2O3 at 1300ºC. This mixture is then cooled at 2ºC an hour over an eight day period. After this time, the temperature is at 915ºC and the flux is still m
Discussions
Become a Hackaday.io Member
Create an account to leave a comment. Already have an account? Log In.