expanded metal weight reduction
TRANSCRIPT
Extreme weight reduction using expanded aluminum mesh
FEA analysis of a structural member
8/31/2016
Don Blanchet
3B Associates
Goals
Reduce the weight of a small but critical motor mount component for a light single person aircraft.
Due to cost limitations a graphite fibrestructure was ruled out.
Trade study of original solid machined design with metal mesh design.
Location of critical component a part of the engine mount assembly
Solid plate design 6061-t6 aluminum
~ 7 x 4 x 0.5 inches Weight = 0.62 lbs
FEA mesh
Fixed boundary conditions
First resonant frequency920 hz
Static stress = 15,750 psi
Oposing 100 lb loads
Elastic twist deformation= .080 inch
Aluminum mesh core design – vacuum brazed
.010 thick expanded metal mesh
.010 thick cover platesBrazed to mesh both sides
Total Weight = 0.23 lbs
FEA mesh with covers
FEA mesh without covers
First resonant frequency= 1329 hz
Static stress = 32,330 psi
Elastic twist deformation= .150 inch
Results summary
Analysiscase
ResonantFrequency
hz
MaximumStress
psi
Maximumelastic
Deflectioninch
Weightlbs
Factor of SafetyYield
strength = 42,000 psi
Solidmachined
plate920 15,750 0.080 0.62 2.7
Expandedaluminum
core1329 32,330 0.150 0.23 1.3
Conclusions
There is a 63% weight savings using the vacuum brazed expanded metal core design.
The stress design margin will be reduced to 30%.
Very critical weight savings can be attained a at reasonable cost increase.