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Pultrusion or Vacuum injection moulding?
- Thread starter carbongr
- Start date
Some general advice is possible, but without knowing more about the form of structure to be made it's hard to be genuinely helpful.
Pultrusion with unidirectional fibres can give 70% fibre volume fraction, which will give the greatest rigidity (stiffness) for a given bar size with deformation along the bar axis (bending or axial). Pultrusion isn't really that well suited to producing sheets and is a bit limited for non-unidirectional fibre direction options.
Vacuum injection (VARTM, etc.) is more suited to somewhat lower fibre volumes (often 50-55%) and large sheet areas, with preference usually given to cloth and non-crimp fabric reinforcements, though small fitting-like components can also be infused economically.
The two manufacturing methods are sufficiently different that usually they are not considered alternatives for a given form of structure.
An exception might be beams of constant section such as those sometimes used in truck beds.
What are you making?
Pultrusion with unidirectional fibres can give 70% fibre volume fraction, which will give the greatest rigidity (stiffness) for a given bar size with deformation along the bar axis (bending or axial). Pultrusion isn't really that well suited to producing sheets and is a bit limited for non-unidirectional fibre direction options.
Vacuum injection (VARTM, etc.) is more suited to somewhat lower fibre volumes (often 50-55%) and large sheet areas, with preference usually given to cloth and non-crimp fabric reinforcements, though small fitting-like components can also be infused economically.
The two manufacturing methods are sufficiently different that usually they are not considered alternatives for a given form of structure.
An exception might be beams of constant section such as those sometimes used in truck beds.
What are you making?
- Thread starter
- #4
spudpeeler
Materials
If the part count is high pultrusion is the best way forward. If the part count is not in the hundreds I would consider a vacuum molding process or press molding with prepreg.
If you are manufacturing UD fiber bars, use pultrusion.You can also make a hand pultrusion unit if you don't require continuous production. It is difficult to make rods using vaccum bagging and achieve better stiffness. Pultrusion yields better stiffness too.
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- #7
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