Skip to main content

Questions tagged [composite]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
0 answers
20 views

Seeking Advice: Improving Resin Application in Honeycomb Lamination for a Sustainable Project

I am trying to laminate a honeycomb structure with a fiberglass and resin reinforcement. However, I have problems because a large amount of resin falls through the holes of the honeycomb and the final ...
BeeSwell's user avatar
0 votes
0 answers
16 views

How would you go about the steel columns being adjacent where an expansion joint is expected?

The building is a steel building with a composite slab. The expansion joint is required because the building is 60m in length. The problem is where the expansion joint is expected, the columns are ...
Yafet Bouchagra's user avatar
0 votes
0 answers
24 views

Case studies in Carbon Fiber composite tubes to verify FEA

Whenever I build a model of something new, I like to have some analytical results that I can compare with my model so I can reassure myself the model is correct. I have some resources that show me ...
user3533030's user avatar
0 votes
0 answers
29 views

Why don't we calculate buckling in composite beams?

I have a frame, it consists of steel beams and my flooring is a composite deck. It consists of composite beams that are hinged to my steel frame beams. Composite beams do not transfer moments. Now, ...
Bilgehan Yılmaz's user avatar
0 votes
0 answers
18 views

What does "dc" stand for in this Positive Bending Moment for Plastic resistance of a composite concrete slab formula?

I'm designing a building with a composite slab with profile sheeting and steel structure, while trying to test the resistance of the composite slab in "composite phase" to bending moment I ...
Yafet Bouchagra's user avatar
1 vote
0 answers
38 views

Optimizing the layer lines of a 3d printed part, based on subjected forces

I was directed here from the 3d printing stackexchange... For years I have been fortunate to only have had to make 3D prints that don't require a large amount of force on them. But recently (since ...
nick carraway's user avatar
0 votes
1 answer
48 views

Why the size of top and bottom rollers is different in three point bend test?

In a short beam shear testing of polymers, the configuration is such that the top (loading) roller is bigger than the bottom (support) rollers. Why is this the case, and what happens when the size of ...
Uz1's user avatar
  • 1
0 votes
1 answer
45 views

How to find Tensile Modulus of a layer of Plain Woven GFRP with GSM of Fabric given

I need to Input "E" the tensile modulus for analysis of a composite layer made from Plain Woven E-Glass Epoxy composite material. I know the GSM (g/m^2) of fabric is 106. Using GSM =106, ...
Rehan Jamshed's user avatar
0 votes
0 answers
94 views

Composite Beam Theory - Calculating torsion and beam deflection of a composite beam made up of a pipe inside a pipe

I am trying to calculate two things. First the beam deflection of my model after bending and second angle of twist after applying torque. My model is composed of two tubes (cylindrical hollow beams). ...
Curry's user avatar
  • 1
1 vote
1 answer
59 views

Confusion about boundary condition (steady heat conduction)

Given a composite material composed of two materials each having different thermal conductivities and heat flux vectors. This leads us to write the two properties as position dependent. One thing I ...
user134613's user avatar
0 votes
1 answer
189 views

Why don't people use sodium silicate to bind fiberglass instead of epoxy?

I tried to search for it, but I couldn't find any answer on the subject. I could only find that water glass is normally used mixed with other stuff like sand to make casting molds. In my mind it would ...
Fulano's user avatar
  • 51
0 votes
1 answer
74 views

Failure criteria for CFRP single plate bolted joint

Which equation can be used to find failure based on ply orientation. Tension,shear & bearing faliure to validate against fem analysis
SACHIN SAJIKUMAR's user avatar
2 votes
2 answers
646 views

What Are The Recommended Binding Methods For A Carbon Fibre Chassis Frame?

I'm looking for a simple way (that doesn't require high pressure chambers or state of the art tools) to permanently bind a set of carbon fibre pieces in order to make the frame of a chassis that could ...
Alfred's user avatar
  • 23
1 vote
5 answers
247 views

Exactly what makes steel-concrete composite beam better than pure steel?

A composite action beam may have a concrete section the top, carrying the compression load, and steel at the bottom, carrying tension. But I have always thought that concrete had lower strength for a ...
Abdullah is not an Amalekite's user avatar
1 vote
0 answers
18 views

why did my ceramic matrix composite turn out brittle as snow?

I have attempted making a ceramic matrix composite (cmc) by wetting glass fiber cloth with waterglass and baking it at 200°C. The resulting material disintegrated on touch. Unwetted fibers did not ...
Francis L.'s user avatar
3 votes
0 answers
54 views

Is there any formula to model the effective Young's Modulus of a fluid-filled spherical shell?

I am creating composites of a host epoxy and filler particles which are thin-walled fluid-filled shells. Using the Halpin-Tsai equations, for example, I can predict the bulk composite Young's modulus ...
Trevor Buckner's user avatar
-1 votes
1 answer
703 views

Why use Mylar for vacuum bagging

During my work at a composites workshop I got some experience with composites and vacuum-bagging. I decided to make a foam core wing for a model aeroplane. I checked for some internet info on it, and ...
GZoltan's user avatar
1 vote
1 answer
473 views

Bending stiffness of composite shaft

What is the method to compute the effective bending stiffness "EI" of a composite structure, in this case a shaft (as seen below). The shaft is hollow with outer radius $r_{o}$, inner radius ...
Omar's user avatar
  • 19
-1 votes
1 answer
55 views

How to know the material of key-top?

There are keys (push buttons) on the front panel of an avionics device that fits inside the aircraft cockpit. I need to know the material of which those key-tops are made from. I can guess the ...
scico111's user avatar
  • 109
1 vote
0 answers
34 views

What's the rationale for closely spaced standard LVL sizes?

Generally LVLs in the US seem to conform to heights that were historically used for solid lumber. e.g., 5 1/2" is the height of a nominal 2x6. This makes sense because presumably LVLs had easier ...
StayOnTarget's user avatar
-1 votes
1 answer
179 views

Composite materials

I am writing to ask about a unidirectional composite material T700/M21, how can I understand why this material has the same modulus of elasticity in direction 2 and 3 which means (E2 = E3,E1) in an ...
user avatar
1 vote
0 answers
73 views

How do I define properties orientation in a 2D short random fibers composite? ABAQUS

I generated different 2D microstructures with different fibers volumetric fraction (basically a square representing the matrix and a lot of small rectangles inside, with different measures and random ...
Federico De Bianchi's user avatar
1 vote
0 answers
326 views

How can I calculate the shear modulus (Gxy) for the material of a composite laminate [10/-10/-10/10] using test data?

I have the data from a tensile test including axial displacement, force, and strain, as well as E1, E2, Nu12, and Nu21 for the carbon fiber prepreg. I am trying to use this axial data to calculate Gxy ...
Renato's user avatar
  • 11
0 votes
3 answers
444 views

Composite beam- increase in bending moment due to reinforced steel

While trying to solve this question and using the flexure formulas of bending for composite beams I obtained a lower value of moment for steel than for aluminum.How is that possible?
Roy Rizk's user avatar
0 votes
2 answers
170 views

What are equations related to the compaction of composite metal powders?

Say I am trying to create a metal composite and have a mixture of 3 different metal powders each with varying weight %'s. I'm going to compact them into the shape of a ring by applying a force P. The ...
Davin's user avatar
  • 15
3 votes
2 answers
660 views

How to compute core stress in honeycomb structure?

Assume I have a honecomb(sandwich) panel under distributed normal load. Each edge of this panel is simply supported(pinned) as on the picture below: The problem is how to find the core stresses σ-z (...
Eugene's user avatar
  • 63
-1 votes
1 answer
106 views

Why do people build the core of a sandwich structure using composite

Usually I see composite as a laminate wrapped around the core of a sandwich structure. Usually in loading such as bending the bending stress is the highest furthest away from the neutral axis, while ...
Kai's user avatar
  • 1
0 votes
0 answers
65 views

Buckling of composite plates help

I am trying to write code for the buckling of composite plates using the Ritz approximation but I can't understand something. According to Reddy (Mechanics of laminated composites), this is the ...
Tristan Greenwood's user avatar
1 vote
2 answers
231 views

Young's modulus for composite auxetic material

If you look at the screenshot you will see a composite auxetic material. How would you calculate the E-modulus for it? Is it as simple as the rule of mixtures, ...
Niklas's user avatar
  • 145
0 votes
1 answer
84 views

Why is graphlite so strong in tension?

This comes from the composites store website: These high performance carbon shapes are produced by packing a high volume of carbon fiber into epoxy resin under tension resulting in an unmatched ...
juggler's user avatar
  • 203
1 vote
1 answer
966 views

How to calculate scarf ratio or lap overlap for composites?

I'm building a plane, and one of the solutions I've thought of for connecting the wing spars to the fuselage involves connecting carbon fiber parts. As mentioned in this answer, I found this ...
juggler's user avatar
  • 203
1 vote
1 answer
3k views

For the machine element shown, locate the X, Y and Z coordinate of the center of gravity

QUESTION: My working: I had divided the body into 5 common shapes which are shown here: now that I'm solving for x bar, y bar, and z bar I find it difficult in finding the x, y and z directions. ...
Surdz's user avatar
  • 121
2 votes
2 answers
2k views

Can we make engineering grade paper mache by improving on the paper?

Can we bring engineering to the paper in paper mache? It's a mix of a binder and a reinforcing matrix. PVA is common for the binder and is strong. That's fine as I think it's strong enough and ...
Paul Uszak's user avatar
1 vote
1 answer
197 views

Milling aramid composites produces unwanted fuzz at surface

I use standard end mills for cutting carbon fibre sheets. Generally the cutters are 2 to 3 mm diameter, with a flute length of about 8 mm. I use 3- and 4-flute end mills. These work quite well if they ...
Donald Gibson's user avatar
2 votes
2 answers
261 views

Assessment of a concrete beam being strengthened by an additional steel member

Hi there (from Europe), I am completing what should be a relatively quick assessment for the client, but I have started to second guess my self and would like some reassurance. Essentially the job ...
Smeato's user avatar
  • 364
2 votes
3 answers
529 views

Can you postcure epoxy composites outside the mold?

Say I make a fiberglass/epoxy part on a plastic mold, and it cures at room temperature. The epoxy system calls for a postcure at 250F, but the mold cannot withstand 250F. If I take off the part and ...
quantumkayos's user avatar
3 votes
1 answer
82 views

Can the phrases “carbon fibre reinforced polymer composites” (CFRP) and “carbon fibre-epoxy composites” be used interchangeably?

Does the "polymer" in CFRP directly and unambiguously imply the use of an epoxy resin?
aerodokuu's user avatar
1 vote
1 answer
213 views

Design a composite material with good wear resistance and electrical conductivity

For a electrical switching device which opens and closes frequently and forcefully. Would a combination of a soft polymer matrix and a conductive metal fibre be a good choice for this? While polymer ...
zero's user avatar
  • 201
3 votes
2 answers
475 views

Impact load of a bullet on a laminate

Can anyone tell me how to go about this problem? There is a square shaped laminate (polyethylene fiber and epoxy resin composite) that is constrained on one side. A gun is fired and the bullet hits ...
nihal's user avatar
  • 145
4 votes
1 answer
925 views

How do I cut a crack into a polymer/plastic?

We need to cut a very thin crack into a polymer plate for a research project. The closest thing to what we are looking for is Wire EDM but since the polymer we are using is not conductive we cant use ...
Murad Nazari's user avatar
1 vote
2 answers
8k views

How do I calculate the structural properties of a fiberglass laminated wood panel?

I'm constructing 2.2 meters span, 1 m wide shelf. Want to make it cheap but thin. I'm planning to use 18mm thick OSB board and reinforce it with a layer of stronger material stuck to it's bottom. My ...
Gleb's user avatar
  • 163
1 vote
1 answer
1k views

How strong is the adhesion between UHMWPE Fiber and Epoxy Resin?

How strong is the adhesion between Ultra High Molecular Weight Polyethylene(UHMWPE) Fiber and Epoxy Resin normally? If we take the UHMWPE fiber sheet as it is without subjecting it to any chemical or ...
nihal's user avatar
  • 145
1 vote
1 answer
288 views

Impact of mold material in carbon fiber part finish

Does the material with which I make the mold for carbon fiber parts affect the finish the part will get? If it does, I would like to understand how a given material may affect the finish. Another ...
user1790813's user avatar
5 votes
1 answer
173 views

How do I interpret the curing pressure of a composite from this data sheet?

A question asked about the necessary curing pressures for a composite resin in the autoclave. Looking through the corresponding datasheet (HexPly F155), I'm confused: Cure Procedure Apply ...
BeyondLego's user avatar
5 votes
1 answer
6k views

How do I calculate an estimate for the properties of a composite material?

For a given laminate made of composite material (composed of fibers oriented in a carefully designed sequence coated and embedded in a matrix material), where can I begin estimating the stiffness and/...
Mark's user avatar
  • 5,333