2013 12-05-sirris-materials-workshop-fgm-magien
DESCRIPTION
Sirris Materials Workshop - 5 december 2013 - Functional Graded Materials with Additive Manufacturing - Julien Magnien, SirrisTRANSCRIPT
What you should know about FGM Sirris Materials day 2013
Introduction Principle & description History Applications Manufacturing methods Pros and cons Conclusions
Principle & description A Functionally Graded Material (FGM) is a substance in which properties,
composition and/or structure is not homogenous. There is a controlled spatial distribution of these characteristics to optimize the part made of this FGM.
Example with a turbine blade :
Erosion & heat
weight
Pressure &
vibration
=> Ceramic on the
external surface
=> Metal matrix
=> Light weighted core
Principle & description FGM is composite 2.0 :
Composite Sharp interface Risk of delaminating Weakness and strength
everywhere
FGM Smooth transition Very good bond Volume properties
distribution material adaptation for
specific application.
The whole part is a bit ductile and a bit hard, homogenously
This region is largely hard
This region is largely ductile
History : FGM in Nature :
Bamboo fibre reinforced biocomposites: A review - H.P.S. Abdul Khalil, I.U.H. Bhat, M.Jawaid, A. Zaidon, D. Hermawan, Y.S. Hadi - Materials & Design - Volume 42,
December 2012, Pages 353–368
http://www.britannica.com
First human FGM in 1985. challenge : 1000°C temperature gradient over a thickness of only 10 mm :
700°C
10 mm
History :
1700°C
Outside Inside
http://en.wikipedia.org/wiki/Functionally_graded_material
Cutting tool : Mitsubishi Carbide developed “Miracle Coated
Indexable Inserts” : carbide substrate
Applications :
http://www.mitsubishicarbide.com/mmc/en/product/pdf/b/b031g.pdf
Applications Architecture :
Applications : Articulated mechanical parts :
Biomimesis in Standford
Applications : Thermal choc resistant for thermal barrier FGM:
Applications : Tailored thermal conductivity property for thermal management :
Heat removal in engine bloc Cooling of electrical components
Definition of a ceramic (alumina foam)/metal (aluminum) gradient. The ceramic is an insulator which protects cold devices from heat and aluminum drives heat away from hot devices
Applications : Graded porosity of bones implants for better bone re-
colonization :
Applications : Graded porosity for adapted mechanical behavior :
Applications : Functionally graded implants :
http://research.unt.edu/ises/advanced-metallic-materials
Applications : Constant dielectric characteristic over temperature:
5 layers/compositions => ~composite
21 layers/compositions, same thickness => FGM
21 layers/compositions, variable thickness
http://144.206.159.178/ft/677/43119/781575.pdf
Applications : Thermal dilatation in High-Intensity Discharge lamp :
http://www.toto.co.jp/E_Cera/lampparts/fgm_electrode.htm
Applications : Reduced electrical field stresses in power supply insulators :
Δ = 100 kV
uniform
FGM
http://ir.nul.nagoya-u.ac.jp/jspui/bitstream/2237/14528/1/1097.pdf
Applications Buffer section between 2 different materials :
Material distribution in the FGM layer
Applications : Manufacturing of an ablation resistant SiC/C FGM:
Higher
number of layers is
better for residual thermal stresses
Linear evolution is better for residual thermal stresses
Processing methods Classification :
Homogenizing Segregating Constitutive
Processing methods – powder metallurgy Formation of graded powder compact (green) : Stepwise change : Die compaction (powder stacking) Limited N° of layers (< 10, 1mm/layer) Discontinuous process Low productivity
Processing methods – powder metallurgy Formation of graded powder compact (green) : Stepwise change : Sheet lamination Complex shapes achievable Sheets are expansive (powder rolling or
tape casting -> “green” state) Assembly by hot pressing
Processing methods – powder metallurgy Formation of graded powder compact (green) : Stepwise change : Wet powder spraying : Coating on complex surface Layer thickness from 50 µm -> ~1 mm
Processing methods – powder metallurgy Formation of graded powder compact (green) : Stepwise change : Slurry dipping : Thin coating by dipping in different
baths. Suitable for series production. Enter porous body by capillarity.
Processing methods – powder metallurgy Formation of graded powder compact (green) : Stepwise change : Solid freeform processes : Hot powder-binder mixtures extruded in
a mixing nozzle.
Processing methods – powder metallurgy Formation of graded powder compact (green) : Continuous change : Gravity sedimentation: Material choice limited Inter-particles interaction in highly
loaded suspensions Simple and repeatable
Processing methods – powder metallurgy Formation of graded powder compact (green) : Continuous change : Electrophoretic deposition: Continuous change of suspensions Different electrophoretic mobility Risk of bubble entrapment Several mm thick
Processing methods – powder metallurgy Formation of graded powder compact (green) Continuous change : Thermal spraying : Gradient coating on existing parts “Mechanical” bond
Processing methods – powder metallurgy Melting processes : Laser/plasma cladding : Gradient coating on existing parts.
Inconel 718 -> SS 316L
Pure SS 316L
SS 316L -> Inconel 718
Pure Inconel 718
SIRRIS
Processing methods – powder metallurgy Melting processes : Centrifugal/sedimentation casting : Solubility or wetting problems
Review Fabrication of Functionally Graded Materialsunder a Centrifugal Force Yoshimi Watanabe and Hisashi Sato
Processing methods – powder metallurgy Melting processes : Controlled mold filling : FGM width controlled by the degree of
solidification of the first melt
Processing methods – powder metallurgy Melting processes : Infiltration processing : Preform (metallic foam, pre-sintered green
part,…) with porosity gradient Infiltration by lower melting component Open pores/wetting needed
Processing methods summary
Processing techniques for functionally graded materials - B. Kieback, A. Neubrand, H. Riedel – materials science & engineering A - 2002
Software developments New file format to develop the famous “.stl”, with
its own standard : ASTM F2915-12 “AMF” stands for “Additive Manufacturing Format” XML script Open source Volume capabilities for FGM or lattices
A lot of characteristics can be selected for each voxel such as color, texture, material, density,…
http://amf.wikispaces.com/ http://www.astm.org/Standards/F2915.htm
Software developments Another FGM software from the MIT : Spec2Fab
http://spec2fab.mit.edu/
Pros
Solution for incompatible materials combinations
Improve materials efficiency Increase part lifetime
Cons
Processes hard to control Complex phenomenon occur
(shrinkage, dilution, distortions,…)
Expansive techniques
Pros and Cons :
Conclusions FGM = composite 2.0 More efficient use of materials capabilities Already in the industry Applicable in every technological fields.
=> Thank you for your attention !