Strength Validation
Materials
Face Sheet Testing
These properties will be needed to generate a model of our face sheets in ansys
Properties needed - For each bullet point, 2 have the same value, meaning we need to find 18 individual values
Youngs Modulus (x,y,z)
Poisons ratio (xy,yz,xy)
Shear Modulus (xy,yz,xz)
Tensile Strength (x,y,z)
Compressive Strength (x,y,z)
Shear Strength (xy,yz,xz)
Tensile Strain Limit (x,y,z)
Compressive Strain Limit (x,y,z)
Shear Strain Limit (xy,yz,xz)
Face sheet testing will be broken into a few different tests in order to get all the properties needed
Tensile Test
Tensile testing will be conducted in accordance (or as close to as possible) to ASTM D3039 with a 57.5% min fiber volume fraction
Will wrap test pieces with emery cloth and the clamp
10 in by 1 in
Test strips of 11 in by 6 in
Will be measuring for ultimate tensile strength, tensile modulus, and Poisson's ratio
5 tests of each type will be performed to account for variability
Tests being preformed
0 deg 4 ply; 3k Twill; West Systems 105/209 (T1)
cut 4 11x6 in strips 3k Twill
0 deg 4 ply; 3k Twill; Fibre Glast System 2000/2120 (T2)
cut 4 11x6 in strips 3k Twill
0 deg 4 ply; 3k Plain Weave; West Systems 105/209 (T3)
cut 4 11x6 in strips 3k Plain Weave
0 deg 4 ply; 3k Plain Weave; Fibre Glast System 2000/2120 (T4)
cut 4 11x6 in strips 3k Plain Weave
0/45/-45/90 ply; 3k Twill; West Systems 105/209 (T5)
cut 2 11x6 in strips 3k Twill
cut 2 11x6 in strips 3k Twill 45 deg
0/45/-45/90 ply; 3k Twill; Fibre Glast System 2000/2120 (T6)
cut 2 11x6 in strips 3k Twill
cut 2 11x6 in strips 3k Twill 45 deg
0/45/-45/90 ply; 3k Plain Weave; West Systems 105/209 (T7)
cut 2 11x6 in strips 3k Plain Weave
cut 2 11x6 in strips 3k Plain Weave 45 deg
0/45/-45/90 ply; 3k Plain Weave; Fibre Glast System 2000/2120 (T8)
cut 2 11x6 in strips 3k Plain Weave
cut 2 11x6 in strips 3k Plain Weave 45 deg
Total cuts:
12 11x6 in strips 3k Twill 0 deg
4 11x6 in strips 3k Twill 45 deg
12 11x6 in strips 3k Plain Weave 0 deg
4 11x6 in strips 3k Plain Weave 45 deg
Shear Testing
In-plane shear
Testing will be conducted in accordance to ASTM D3518
5 tests of each type will be performed to account for variability
Specimen Dimensions
Width: 1 in.
Length: 8 in.
[45°, -45°] alternating ply; Total of 8 ply
Tabs (as referenced in ASTM D3039) are not required
Tests to be performed (all [45, -45] 8 ply):
3k Twill; West Systems 105/209 (S1)
cut 8 9x6 in strips 3k Twill 45 deg
3k Twill; Fibre Glast System 2000/2120 (S2)
cut 8 9x6 in strips 3k Twill 45 deg
3k Plain Weave; West Systems 105/209 (S3)
cut 8 9x6 in strips 3k Plain Weave 45 deg
3k Plain Weave; Fibre Glast System 2000/2120 (S4)
cut 8 9x6 in strips 3k Plain Weave 45 deg
Total cuts:
16 9x6 in strips 3k Twill 45 deg
16 9x6 in strips 3k Plain Weave 45 deg
Out-of-plane shear
Testing will be conducted in accordance to ASTM D6415
Specimen Dimensions(CURVED SPECIMEN):
Length: L>3.5in. ~ 4in. (length of each straight section)
Width: 1 in.
Inner Radius(at bend): 0.25 in.
Thickness: 0.08-0.50 in. → 10 ply(all 0°)
Tests to be performed(all 0° 10 ply)
3k Twill; West Systems 105/209
3k Twill; Fibre Glast System 2000/2120
3k Plain Weave; West Systems 105/209
3k Plain Weave; Fibre Glast System 2000/2120
Compression
ASTM D6641 - mix loading
Will need to design fixture(shouldn’t be bad)
Looks like strain gauges are typically used(extensometer possibility?)
Specimen Dimensions
Width: 0.5 in.
Length: 5.5 in. (make longer then cut short so the ends aren’t tapered[6 in.])
Tabs:
Fiberglass
Rectangular(no taper)
Thickness: ~1.6mm(0.06in.) (as long as tabs aren’t so thick that they can’t properly transfer shear stresses, then it’s ok)
Gauge Length: Should be at least ~0.5in(for strain gauges) but not too large so that buckling becomes an issue
Tests to be performed(all 8 ply)
0 deg 8 ply; 3k Twill; West Systems 105/209
cut 8 6x3.5 in strips 3k Twill
0 deg 8 ply; 3k Twill; Fibre Glast System 2000/2120
cut 8 6x3.5 in strips 3k Twill
0 deg 8 ply; 3k Plain Weave; West Systems 105/209
cut 8 6x3.5 in strips 3k Plain Weave
0 deg 8 ply; 3k Plain Weave; Fibre Glast System 2000/2120
cut 8 6x3.5 in strips 3k Plain Weave
0/45/-45/90/90/-45/45/0 ply; 3k Twill; West Systems 105/209
cut 4 6x3.5 in strips 3k Twill
cut 4 6x3.5 in strips 3k Twill 45 deg
0/45/-45/90/90/-45/45/0 ply; 3k Twill; Fibre Glast System 2000/2120
cut 4 6x3.5 in strips 3k Twill
cut 4 6x3.5 in strips 3k Twill 45 deg
0/45/-45/90/90/-45/45/0 ply; 3k Plain Weave; West Systems 105/209
cut 4 6x3.5 in strips 3k Plain Weave
cut 4 6x3.5 in strips 3k Plain Weave 45 deg
0/45/-45/90/90/-45/45/0 ply; 3k Plain Weave; Fibre Glast System 2000/2120
cut 4 6x3.5 in strips 3k Plain Weave
cut 4 6x3.5 in strips 3k Plain Weave 45 deg
Total cuts:
24 6x3.5 in strips 3k Twill 0 deg
8 6x3.5 in strips 3k Twill 45 deg
24 6x3.5 in strips 3k Plain Weave 0 deg
8 6x3.5 in strips 3k Plain Weave 45 deg
Known values
Ultimate Tensile (z) - Epoxy Data Sheet
Compressive Yield (z) (simplifying yield to ultimate) - Epoxy Data Sheet
Tensile Strain (z) - Epoxy Data Sheet
Datapoints collected through face sheet testing
Ultimate Tensile (y) - ASTM D3039
Tensile Modulus (y) - ASTM D3039
Tensile Strain Limit (y) - ASTM D3039
Poisons Ratio (xy) - ASTM D3039
Ultimate Compressive (y) - ASTM D6641
Compressive Modulus (y) - ASTM D6641
Compressive Strain Limit (y) - ASTM D6641
Ultimate Shear - in plane (xy) - ASTM D3518
Shear Strain Limit (xy) - ASTM D3518
Shear Modulus (xy) - ASTM D3518
Ultimate Shear - out of plane (xz) - ASTM D6415
Shear Strain Limit (xz) - ASTM D6415
Calculated/extrapolated values - For note: Same as y, we are making the assumption that since our ply is symmetrical, it will
Ultimate Tensile (x) - Same as y
Tensile Modulus (x) - Same as y
Tensile Strain Limit (x) - Same as y
Ultimate Compressive (x) - Same as y
Compressive Modulus (x) - Same as y
Compressive Strain Limit (x) - Same as y
Ultimate Shear - out of plane (yz) - Same as xz
Shear Strain Limit (yz) - Same as xz
Other Tests
For these 4 values we will be compression testing the epoxy, maybe using ASTM 695
Poisons Ratio (yz, xy) - If I’m not wrong, poisons ratio of resin should be xz and yz since
Compressive Strain (z)
Compressive Stress (z) (for System 2000 epoxy)
Ask Davies about how a compression test would be done:
Ask about specimen geometry
Ask about what kind of fixture is necessary
Categories Completed
Tensile Strength
Compressive Strength
Shear Strength
Shear Strain Limit
Tensile Strain Limit
Panel Testing
These properties are needed
Properties Needed
In plane shear (ASTM C273)
Will be used to find the in-plane shear strength and modulus
Specimen Dimensions: 3 x 9 in.
5 or more panels
Use Loctite E120HP to bond face sheet to metal sheet
Flexural Strength (ASTM D7249)
Our panels will be mainly loaded in bending, and this will give us our failure point in those loading conditions
4 point bending
Specimen dimensions: 24 by 3
5 to 10 panels
Measuring total force of failure
In-plane compression (ASTM C364)
Will be used to find edge-wise compression strength
Useful for judging load-carrying capacity
Specimen dimensions: 3 x 3 in. (If one side ends up longer, let that be the lengthwise direction)
Head displacement: 0.50mm/sec
5 or more panels