Analysis of the micro-cracking behaviour of carbon fibre reinforced flywheel rotors considering residual stresses

2018 ◽  
Vol 204 ◽  
pp. 587-593 ◽  
Author(s):  
I. Koch ◽  
G. Just ◽  
F. Otremba ◽  
M. Berner ◽  
M. Gude
Keyword(s):  
Residual Stresses ◽  
Carbon Fibre ◽  
Flywheel Rotors

Thermally induced residual stresses in carbon fibre-reinforced aluminium-matrix composites

1992 ◽  
Vol 11 (13) ◽  
pp. 947-949 ◽  
Author(s):  
S. N. Patankar ◽  
C. Suryanarayana ◽  
D. Blackketter ◽  
F. H. Froes
Keyword(s):  
Residual Stresses ◽  
Carbon Fibre ◽  
Aluminium Matrix ◽  
Matrix Composites ◽  
Thermally Induced ◽  
Aluminium Matrix Composites

scholarly journals Influence of Reversed Fatigue Loading on Damage Evolution of Cross-Ply Carbon Fibre Composites

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1153 ◽  
Author(s):  
Just ◽  
Koch ◽  
Brod ◽  
Jansen ◽  
Gude ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Carbon Fibre ◽  
Crack Formation ◽  
Crack Opening ◽  
Local Stress ◽  
Fatigue Loading ◽  
Stress Concentrations ◽  
Delamination Growth ◽  
Stress Ratios ◽  
Carbon Fibre Composites

Microcrack formation and delamination growth are the main damage mechanisms in thefatigue of composites. They lead to significant stiffness loss, introduce stress concentrations andcan be the origin of subsequent damage events like buckling or fibre breakage, especially in case ofshear and compression stresses during load reversal. Fatigue experiments of carbon fibre reinforcedlaminates were conducted at several stress ratios and analysed in terms of crack and delaminationgrowth. These investigations were accompanied by microscopic imaging, digital image correlationand finite element modelling to take into account the effects of residual stresses and crack closure.It was found that residual stresses significantly change the local stress ratio in off-axis layers andlead to residual crack opening of inter fibre cracks. These cracks remain open and close under highcompression loadings only. Furthermore, crack formation under pulsating compression loadingturned out to be driven by residual stresses leading to perpendicular cracks as observed underpure tension loading. The experimental findings further confirm the severe detrimental effect oftension-compression loading on crack formation and delamination growth compared to pulsatingtension-tension or compression-compression loads.

scholarly journals Modelling of the Initial Failure of Cfrp Structures by Partial Discretisation: Amicro / Macro-Mechanical Approach of First Ply Failure

2004 ◽  
Vol 13 (5) ◽  
pp. 096369350401300 ◽  
Author(s):  
Bodo Fiedler ◽  
Stefan Holst ◽  
Thomas Hobbiebrunken ◽  
Masaki Hojo ◽  
Karl Schulte
Keyword(s):  
Residual Stresses ◽  
Carbon Fibre ◽  
Composite Structures ◽  
Tensile Tests ◽  
Reinforced Composites ◽  
Element Analysis ◽  
Matrix Cracks ◽  
Transverse Tensile ◽  
Bending Load ◽  
Fibre Reinforced Composites

The formation of transverse matrix cracks is the early failure in carbon fibre reinforced composites (CFRP). Unidirectional laminates with 90° fibre orientation were tested by transverse tensile tests and in situ under 3 point bending load in the scanning electron microscope (SEM). Finite element analysis were carried on the microscopic level hexagonal unit cell of fibre and matrix, as on the macroscopic level based on homogenized fibre and matrix properties as well. To link the micromechanical approach with the homogenized description of composite structures was done by transferring boundary conditions from one model to the other. The influence of the temperature on the Young's modulus, the non-linear stress-strain behaviour and the strength of the matrix on the micro residual stresses and matrix failure was taken into account has been investigated in detail. Process induced thermal residual stresses and matrix failure of unidirectional carbon fibre reinforced composites (CFRP).

Sign in / Sign up

Export Citation Format

Share Document