Damage mechanics Fatigue lifetime FEA and Fatigue damage calculation. Geometry Material property...
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Damage mechanicsFatigue lifetime
Mean load change Prediction models Linear Cycle Mix (LCM) effect Two constants need to be definedConstants change with the type of load spectrumN [cycles to failure]Residual load R [kN]Fatigue load decreasingabcdeComplex loading
Vertical jump approachIndependent of type of load spectrumNo constants need to be definedCan be applied to any type of interaction effectsN [cycles to failure]Residual load R [kN]Fatigue load decreasingabcdComplex loading
Variable amplitude fatigueResults and discussion
Type of load interactionExperimental results (No. of cycles)Miner rule prediction (No. of cycles)LCM approach (No. of cycles)Vertical jump approach (No. of cycles)
L1 = 6.5kN; L2 = 8kNn1=10; n2=5 1706502018501707
L1 = 6.5kN; L2 = 8kNn1=1000; n2=5 18085 32127 21174 17757L1 = 8kN; L2 = 9.5kNn1=10; n2=5 97684518691022L1 = 8kN; L2 = 6.5kNn1 = 10; n2=5129662704199259518
AC DC against CAA surface pre-treatmentStatic strengthCycles to failure for max. fatigue load of 60% of static strength
ACDC SummaryA two-stage anodisation process has been developed to facilitate interphase formation without compromising corrosion protection.
The process is simple, fast and robust.
Initial results show excellent adhesion and corrosion performance comparable to CAA.
4. CONCLUDING REMARKSGiven an understanding of film formation mechanisms oxides can be nanoengineered for optimised adhesion.
Hexavalent chromium chemistry is widely used in Al processing within the aerospace, defence, automotive sectors. Drop-in replacements are urgently sought.
ACDC processes offer additional advantages:environmentally benignsimpleincreased processing speeds.