Single fibre tensile testing Justine Beauson Section of Composites and Materials Mechanics, Department of Wind Energy
Introduction Fibre properties Fibre orientation Matrix properties Mechanical performance of composites Porosity Fibre length Fibre content Fibre packing ability Fibre/matrix interface properties 2
Introduction Favimat+ and Airobot2 from TechTexhno The alternative Manufacturer s data sheet; Card board method ASTM C1557-03 procedure. 3
Presentation The machine The test The results 4
The machine Preparation area Testing area 5 Robot Storage area
The machine Preparation area 6 8 November 2016
The machine Preparation area 7
The machine Preparation area Testing area 8 Robot Storage area
The machine Testing area 9
The Test 1. Linear density test 2. Tensile test 10
The test 1. Linear density test : Resonance frequency : Fibre modulus : Fibre radius 1 2.. 1.. L: gauge length : Linear density : Pre-tensioning Force 11
The test 1. Linear density Carbon fiber 1 2.. 1.. Linear Density T [dtex] Gauge length L: 20mm 1,00 0,80 0,60 0,40 0,20 0,00 0,00 0,50 1,00 1,50 2,00 2,50 3,00 Pretension F [cn/tex] Linear Density T [dtex] 12 Gauge length L: 40mm 1,00 0,80 0,60 0,40 0,20 0,00 0,00 1,00 2,00 3,00 4,00 Pretension F [cn/tex] Linear Density T [dtex] Gauge length L: 50mm 1,00 0,80 0,60 0,40 0,20 0,00 0,00 1,00 2,00 3,00 4,00 Pretension F [cn/tex]
The test 1. Linear density Glass fiber 1 2.. 1.. Linear Density T [dtex] Gauge length L: 20mm 10,00 8,00 6,00 4,00 2,00 0,00 0,00 1,00 2,00 3,00 4,00 Pretension F [cn/tex] Linear Density T [dtex] 10,00 8,00 6,00 4,00 2,00 0,00 0,00 1,00 2,00 3,00 4,00 13 Gauge length L: 40mm Pretension F [cn/tex] Linear Density T [dtex] Gauge length L: 50mm 10,00 8,00 6,00 4,00 2,00 0,00 0,00 1,00 2,00 3,00 4,00 Pretension F [cn/tex]
The test 1. Linear density 1 2.. 1.. 4 14 A Density measured with pycnometer
The test 2. Tensile test 15
The results Glass fibres 1. Linear density 2. Tensile test 16
The results 1. Linear density Comparison vibroscopy / microscopy Linear density, T [dtex] Vibroscopy Cross sectional area [µm 2 ] Microscopy Average diameter measured [µm] Cross sectional area [µm 2 ] Relative difference [%] Fibre 1 5,74 222 17,24 ± 0,24 234 5 Fibre 2 5,79 224 17,32 ± 0,26 236 5 Fibre 3 6,39 247 18,55 ± 0,25 270 11 Fibre 4 4,90 189 16,44 ± 0,75 212 10 Fibre 5 4,02 155 15,04 ± 0,30 178 10 Fibre 6 8,23 318 20,55 ± 0,26 332 6 Fibre 7 5,62 217 17,30 ± 0,18 235 8 Fibre 8 5,47 211 17,02 ± 0,22 228 7 Fibre 9 5,82 225 17,74 ± 0,23 247 10 Fibre 10 5,99 231 17,92 ± 0,22 252 9 Average 8 17
The results 1. Linear density Effect of sizing 50 45 40 35 pristine Percentage 30 25 20 15 Acetone washed 10 5 0 From 3 to 4 From 4 to 5 From 5 to 6 From 6 to 7 From 7 to 8 From 8 to 9 From 9 to 10 From 10 to 11 Linear density [dtex] 18
The results 2. Tensile test Machine compliance Glass fibres The contribution by the load train system and specimen-gripping system to the indicated crosshead displacement, by unit of force exerted in the load train. Gauge length /Modulus (mm/gpa) 1 0,9 0,8 0,7 0,6 0,5 0,4 0,3 0,2 y = 0,0121x + 0,0116 0 20 40 60 80 100 Gauge Length Lo [mm] : Experimental modulus : gauge length : slope of the curve : Actual modulus 19
The results 2. Tensile test Sizing removal Acetone washing to remove sizing Stress [MPa] Stress [MPa] Strain [MPa] 20
The results 2. Tensile test Data post-processing Double fibre tested (strange stiffness, doubled linear density) Gliding in the clamps 4000 The raw data 49 data Deficient test removed 42 data 3500 3000 Stress [MPa] 2500 2000 1500 Stress [MPa] Stress [MPa] 1000 500 21 0 0 1 2 3 4 5 6 Strain [%] Strain [MPa] Stiffness [GPa] Strength [MPa] Average 92,7 2445 Std dev. 90,8 3009 Strain [MPa] Stiffness [GPa] Strength [MPa] Average 80,7 1998 Std dev. 0,6 452
Thanks you for your attention! Justine Beauson Development Engineer DTU Wind Energy Technical University of Denmark Department of Wind Energy Frederiksborgvej 399 Building 228 4000 Roskilde Denmark Direct +45 46775708 jube@dtu.dk www.vindenergi.dtu.dk 22