View
222
Download
0
Category
Preview:
Citation preview
Simfot: Effects of forming methods
on shape distortions of compositesJens Sjölanderjenssjol@kth.se
NFFP6 Simfot – Simulation of composite manufacturing process from forming to demolding
Transfer of results from forming to shape distortion
calculation
Material characterization – Swerea Sicomp
Process induced residual stresses – Saab, Creo Dynamics
Measurement technology – Creo Dynamics
NFFP6 Simfot – Simulation of composite manufacturing process from forming to demolding
Transfer of results from forming to shape distortion
calculation
Material characterization – Swerea Sicomp
Process induced residual stresses – Saab, Creo Dynamics
Measurement technology – Creo Dynamics
Background
We have previously used FE-software to simulate
manufacturing of stacked uni-directional prepreg.
Now in the Simfot project we wanted to combine the results
from forming simulations with shape distortions in an attempt
to simulate the whole process chain
Additionally we want to investigate the effect of different
forming methods on shape distortion
Geometry and material
A double-curved geometry was formed using two different
methods. Hand lay-up and hot drape forming.
Uni-directional prepreg 0.13 mm thick
Stacking sequence [45/-45/90/0]s
Manufacturing methods
Hand layup: Stack was split in to cross-plied pairs
[(45/-45),(90/0),(0/90),(-45/45)] which were formed together
HDF: The whole stack is formed at once at elevated
temperature
Manufacturing angles
U shaped angles which only required 2D-deformation was
formed to investigate the effects of different amount of plies.
Hand layup
8, 16 and 32 layers
Hot drape forming
8, 16 and 32 layers
Simulation
Kinematic: The beam manufactured with hand lay-up was
reproduced using composites modeler in Abaqus
FE-model: The hot drape formed beam was simulated by
using Aniform thus capturing fibre direction due to
interactions between layers and thickness variations due to
in-plane strains.
.post.res .post.msh
oneLayer.py
Displacement.txt
FibDir.txt
thickness.txt
Elem.txt
Node.txt
AniFormToLayup.m
Lager_x.layup
Composites Modeler
stack.layup
Aniform
Abaqus
HDF
Hand Layup
Characterization of material
Inter-ply properties
Rate dependence
Intra-ply properties
Rate and pressure dependence
Shape distortion calculation
Distortions occur due to a
difference in coefficient of
thermal expansion in the in-
plane and out of plane
directions
Modelled by applying a non-
isotropic CTE and a
temperature change
Transfer of results
The results from Aniform where mapped ply by ply into a
layup in composites modeler
The they are then combined into a single layup that can then
be used to generate a solid model
Thickness variation
Radius thickness - experimental
0.26
0.08
0.27
0.11
0.00
0.05
0.10
0.15
0.20
0.25
0.30
2mm 6mm
8 layers
Hand 8
HDF 8
radie
0.18
0.07
0.25
0.10
0.00
0.05
0.10
0.15
0.20
0.25
0.30
2mm 6mm
16 layers
Hand 16
HDF 16
0.12
0.04
0.20
0.07
0.00
0.05
0.10
0.15
0.20
0.25
0.30
2mm 6mm
32 layers
Hand 32
HDF 32
Radie 2 mm
Radie 6 mm
radie radie radie
radie radie
Effect on angle - experimental
1.86
2.43
1.33
1.97
0.00
0.50
1.00
1.50
2.00
2.50
2mm 6mm
8 lager
Hand 8
HDF 8
1.56
1.94
1.321.50
0.00
0.50
1.00
1.50
2.00
2.50
2mm 6mm
16 lager
Hand 16
HDF 16
radie
1.19 1.14
0.74
1.23
0.00
0.50
1.00
1.50
2.00
2.50
2mm 6mm
32 layers
Hand 32
HDF 32
radie
radie radie radie
radie
Radius thinning of zeros
0.262
2 mm HDF 6 mm HDF
Substantial thinning of the zero
degree ply occurs
0°0°
0.0886
0.1953
0.1193
0.2067
0.0000
0.0500
0.1000
0.1500
0.2000
0.2500
2mm 6mm
HDF 8
Hand 8
Preliminary simulation results
Shape distortion straight flange
Shape distortion joggled flange
Conclusion
There is an effect on geometry from the forming process as
well as from the curing process
Especially thickness at the radius seems to be affected
Future work
Characterize material for use in forming simulations
Do shape distortion calculation and compare to new
experimental results
Thank you
Recommended