imtex 2019 additive manufacturing: an overview...nature does always additive manufacturing!!! since...
TRANSCRIPT
IMTEX 2019
Additive Manufacturing:
An Overview
K.P. Karunakaran
IIT Bombay
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
2
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
3
PrinciplePrinciple 1: Divide and conquer
• “Divide and conquer” approach degenerates
complex 3D into several 2D which is easier.
• Vertical growth: Bother only today, not troubled
by the past and future!
4
This approach is responsible for
the stairstep error!
AM is an
automatic process
of manufacturing
objects (parts,
prototypes, tools
and even
assemblies)
directly from their
CAD models
without any
cutters, tools or
fixtures specific to
the object
geometry.
PrinciplePrinciple 2: Need for support mechanism
Scaffolding for a water tank
It is a necessary evil in 3DP like friction or …
Support removal is responsible for further
loss of finish as well as high cost (of raw
material and time)!
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
6
Nothing rotates in nature (except at the extremes of celestial and
atomic scales!)
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Rotation?
7
Is wheel really the greatest
invention of mankind? Could
have been something else? Our
imaginations are blocked by the
symmetry of wheel!
Mathematically simpler horizontal flat surface “z=0” is more
expensive to produce than a cylindrical surface which is
mathematically more complex “x2 + y2 – r2 = 0”
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Rotation? …
8
The
cheapest
machine is
lathe, then
shaper,
milling
machine
etc.
Nothing in nature is flat (2D) or symmetric;
all are 3D, organic and asymmetric.
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Flat? Symmetric?
9
Is writing – expressing the
sense of sound through
symbols, the simplest form of
sense of vision, another worst
invention of mankind? It has
been a major source of
human conflict!
Engineering
graphics –
Effort to
capture 3D on
2D!
• Nothing in nature is homogeneous – different densities and
material compositions at different places
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Homogeneity?
10
• Nature does not make individual parts and assemble
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Assembly?
11
• Nature’s manufacturing has no wastage!
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Assembly?
12
3D Printing Takes Us Closer to the Nature!Characteristics of Nature: Assembly?
13
All these characteristics are because,
Nature never does subtractive manufacturing!
Subtraction means destruction!!
Nature does always Additive Manufacturing!!!
Since 3D printing also uses Additive Manufacturing, it
takes us closer to the Nature. So, it can realize direct
assemblies, complicated ducts, gradient matrix etc.
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
14
Total automation is the foremost advantage of 3D printing.
Objects of any kind of geometric (direct assemblies, non-linear ducts,
custom, difficult, optimal light/lattice structures) or material (any variety
– poly/ metal/ ceramic, non-equilibrium, gradient – mono/ composite/
gradient, porous/lattice, soft/hard) complexity can be produced.
DFM (compromise) vs DFAM (design freedom makes it disruptive).
3D Printing – A Disruptive TechnologyState-of-the-arts
Ge
om
etr
ic (
bo
un
da
ry)
Ma
teria
l (in
teri
or)
15
3D Printing – A Disruptive TechnologyGeometric complexity: Direct assemblies
Thin walled turbine combustion
chamber, produced on EOSINT M 270,
material EOS Nickel Alloy IN 718.
Courtesy: Materialise Solutions, U.K.
Courtesy: EoS, Germany
Courtesy: Stratasys, USA
16
3D Printing – A Disruptive TechnologyGeometric complexity: Non-linear ducts (CCC)
3D Printing – A Disruptive TechnologyGeometric complexity: Customized solutions
Mass customization – redefined!18
3D Printing – A Disruptive TechnologyGeometric complexity: Optimized light/lattice structure
Shape or topology
optimization: Popular
FEA packages now-a-
days have module for
iterating the shape to
remove non-load
bearing matter!
Eg.: Altair’s Optistruct
19
3D Printing – A Disruptive TechnologyMaterial complexity: Gradient and/or non-equilibrium Matrix
Courtesy: Optomec, USACourtesy: Bajaj Auto, Pune Courtesy: ZCorp, USA
20
Total automation is the foremost advantage of 3D printing.
Objects of any kind of geometric (direct assemblies, non-linear ducts,
custom, difficult, optimal light/lattice structures) or material (any variety
– poly/ metal/ ceramic, non-equilibrium, gradient – mono/ composite/
gradient, porous/lattice, soft/hard) complexity can be produced.
DFM (compromise) vs DFAM (design freedom makes it disruptive).
3D Printing – A Disruptive TechnologyState-of-the-arts
Ge
om
etr
ic (
bo
un
da
ry)
Ma
teria
l (in
teri
or)
Anything that can be modelled, can be printed!
21
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
22
CAD model
AM part
(i) Poor surface finish
due to stair-step error
(ii) Irregularities created during
support removal
When surface finish is very poor,
tolerance cannot be better than that!
Issues to be addressedPoor geometric quality: surface finish & accuracy
- Each RP process has a limited
material composition, that too,
in narrow band of properties
FDM – Polymers
(thermoplastics)
SLA – Photo-polymer
SLS/3DP – Good variety from
polymer to metal but one
machine for each.
LOM – Paper
- Inherently anisotropic
- All RP materials are
proprietary and exorbitantly
priced (60-70%). Exorbitantly
priced equipment too in order
to recover IP fast.
- Due to open loop (absence
of human)
- Commercial reasons
- Limited shelf life
Issues to be addressedPoor matrix quality: Less options, anisotropy, shelf life
Issues to be addressedPoor matrix quality: Residual stresses
The aspect ratio in 3D printing is too high. So, layers tend to warp so
much that they hit the blade causing chip off.
The part may have warpage or even breakage,
Matl: Ti64; Size: 83 x 68 x 131; layer thk. = 0.040 (1700); Time: 60 hrs.
MCP Realizer
at LERMPS-
UTBM, Belfort
Stand in front of a CNC machine for 5 min (when it is working!) and
then in from of a AM machine for 5 min. You will find out which is fast!
That is why we do not call it RP any more!!
Issues to be addressedLow build rate
RP
Indirect Processes
AM has linearity of cost
(& time) with quantity.
Issues to be addressedLinearity of cost & time with production volume
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions: Hybridization & Integration of
Multiple Technologies in One Machine
• Conclusions
Outline
28
Emerging Solutions: HybridizationApproach: Add/ Subtract/ Zero
Nomenclature:
Processes - One can replace the other within the group.
Technologies - None can replace the other.
Processes Technologies
Approach: Add/ Subtract/ Zero
Joining: Arc/ Laser/ EB/ Binder
Layering strategies: Hor/ Conf
Kinematics: 3-ax/ 5-ax; Sl/ Par
Preheating
Stress relieving
Face milling
Inspection
Raw stock: Wire/ Strip/ Powder/ … …
Emerging Solutions: HybridizationCombining material addition & subtraction
Additive Stage:
Focus: interior or matrix.
Result: near-net shape.
Subtractive Stage:
Focus: exterior or surface
Result: finished component.
We proposed scan milling using
angle cutters which will permit
higher layer thicknesses without
loss of precision. Alternately 5-
axis motions also are possible.
[JMPT Vol. 105 (2000) – pp. 371-381].
Synergic integration: Competing
processes complement.
Hybrid approach is not new to 3DP community. Eg.:
Early ones:
• Laminated Object
Manufacturing (LOM)
• Solid Ground Curing (SGC)
• Shape Deposition
Manufacturing (SDM)
• ModelMaker II
• HM (KIST, Korea; IITB etc.)
Recent ones:
• Solidscape
• Lumex from Matsuura, Japan
• Sodick, Japan
Emerging Solutions: HybridizationCombining material addition & subtraction
Emerging Solutions: HybridizationEarly hybrid 3D printers: Laminated Object Mfg (LOM)
Emerging Solutions: Hybridization Early hybrid 3D printers: Solid Ground Curing (SGC)
Emerging Solutions: HybridizationRecent hybrid 3D printers: Solidscape; Model Maker-II
Emerging Solutions: HybridizationRecent hybrid 3D printers: Lumex from Matsuura, Jp
Emerging Solutions: Hybridization Recent hybrid 3D printers: Hybrid Layered Mfg. (HLM)
3-axis HLM
5-axis HLM
Multiple torches
MIG→TIG→Laser
3-Axis HLM 5-Axis HLM (Positional) 5-Axis HLM (Continuous)
Monolithic dies
Composite Dies with conformal cooling
Components without undercuts
Components with undercuts
Components with several 3-
axis features in different
orientations
Impeller
Blisks
Emerging Solutions: HybridizationRecent hybrid 3D printers: Capabilities of MIG-HLM
Emerging Solutions: Hybridization Elimination of support using 5-ax deposition in HLM
Emerging Solutions: Hybridization Joining: Arc/ Laser/ EB/ Binder
Nomenclature:
Processes - One can replace the other within the group.
Technologies - None can replace the other.
Processes Technologies
Approach: Add/ Subtract/ Zero
Joining: Arc/ Laser/ EB/ Binder
Layering strategies: Hor/ Conf
Kinematics: 3-ax/ 5-ax; Sl/ Par
Preheating
Stress relieving
Face milling
Inspection
Raw stock: Wire/ Strip/ Powder/ … …
Feedstock: Powder form is more popular. But we use wire because:
Emerging Solutions: Hybridization Different energy sources: Laser with wire
- Bias (we started from MIG)
- Wire has high yield
- Wire gives high integrity
- Single inventory for hybrid energy
sources of laser and MIG
Emerging Solutions: Hybridization Combining diff energy sources: HLM (Laser & MIG)
Desired
layer
3 fine layers of 0.5mm thick in 5-axis using laser.
These may be adaptive too.
3-axis filling
using MIG.
Emerging Solutions: Hybridization Combining diff energy sources: HLM (Laser & MIG)
• Combining two energy sources
• Combining slicing strategies – 3-/5-axis
– discrete adaptive slicing
Emerging Solutions: Hybridization Different energy sources: EB – Its unique advantages
• Higher energy efficiency: EB is
95% whereas laser is 20-25%
• Need of vacuum: No longer a
limitation; high integrity of the
parts
• Higher scanning speeds: 10,000
times faster than laser.
• Versatility for metals:
Conductive, reflective, refractive
materials
• Less capital and running cost
• Right time to start
Emerging Solutions: HybridizationCombining layering strategies and kinematics
Nomenclature:
Processes - One can replace the other within the group.
Technologies - None can replace the other.
Processes Technologies
Approach: Add/ Subtract/ Zero
Joining: Arc/ Laser/ EB/ Binder
Layering strategies: Hor/ Conf
Kinematics: 3-ax/ 5-ax; Sl/ Par
Preheating
Stress relieving
Face milling
Inspection
Raw stock: Wire/ Strip/ Powder/ … …
Planar layers (adaptive & edge types) Conformal layers
Emerging Solutions: HybridizationCombining layering strategies and kinematics
Emerging Solutions: HybridizationCombining layering strategies and kinematics
Emerging Solutions: HybridizationDiff. layering strategies, kinematics: Conformal
Desired
layer
3 fine layers of 0.5mm thick in 5-axis using laser.
These may be adaptive too.
3-axis filling
using MIG.
Emerging Solutions: HybridizationCombining diff energy sources: HLM (Laser & MIG)
• Combining two energy sources
• Combining slicing strategies – 3-/5-axis
– discrete adaptive slicing
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions: Stress Management
• Conclusions
Outline
49
Emerging Solutions: Stress managementStress management: Prevention & cure
Nomenclature:
Processes - One can replace the other within the group.
Technologies - None can replace the other.
Processes Technologies
Approach: Add/ Subtract/ Zero
Joining: Arc/ Laser/ EB/ Binder
Layering strategies: Hor/ Conf
Kinematics: 3-ax/ 5-ax; Sl/ Par
Face milling
Preheating
Stress relieving
Inspection
Raw stock: Wire/ Strip/ Powder/ … …
Emerging Solutions: Stress managementNature of warpage and residual stresses in 3D printing
Tool steel die
broke into two
pieces due to
inadequate
preheating
(> 450°C) and
stress relieving.
Emerging Solutions: Stress managementResidual stress management: Preheating & hammering
Emerging Solutions: Stress managementResidual stress management: Comparison with organisms
Who Type Cause Relieving Methods
Engineering
components
Tensile/
Compressive
Manufacturing
process/ Loading
during use
• Pressure (incl.
vibration)
• Heat
Organisms
including
humans
-do- Day-to-day
working
environment
-do-
(Exercises,
entertainments, trips,
smoking, drinking …)
Emerging Solutions: Stress managementResidual stress management: Comparison with organisms …
A 3kW induction portable heating heating system was fabricated. It
costed hardly Rs. 55,000 but is very effective.
Emerging Solutions: Stress managementResidual stress management: Induction preheating
Emerging Solutions: Stress managementResidual stress management: Pneumatic hammering
a. Preheating
b. Deposition-MIG
c. Deposition-TIG
d. Deposition-laser
e. Face milling
f. Inspection
g. Stress relieving
SSMA → MSMA
Emerging SolutionsIntegrated Multi-Station Multi-Axis HLM
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions: Indigenization and Innovations
• Conclusions
Outline
58
• Equipment is priced
ruthlessly high. Raw
material contributes about
60-70% of cost.
• Our approach:
1. Indigenization
(price/3)
2. + Innovation (price/10)
• Govt supports proposals
generously if Industry
contributes in cash.59
Emerging SolutionsIndigenization and Innovations
• Powder manufacture (metal, plastics & ceramics)
• Software for 3D printing
• Expertise in Generative Design & Lattice Design
60
Emerging SolutionsIndigenization and Innovations
• Principle of AM/3DP
• Claim 1: 3D Printing takes us closer to Nature!
• Claim 2: 3D Printing is a disruptive technology!
• Issues to be addressed
• Emerging Solutions
• Conclusions
Outline
61
• Additive Manufacturing takes us closer to the Nature.
• Its ability to realize certain unique geometric and matrix features
makes it disruptive.
• No process is omni-potent. So, Hybrid processes integrated with
multi-technologies with synergy is the need of the hour.
• Arc (MIG/TIG), laser and EB are useful as deposition/cladding
technologies, each varying in precision, speed and cost and hence
they have their own windows of applications.
• Indigenization and Indigenizations can help us cut down the price of
imported goods by 10. Sand, foam and ice are the materials.
• We are developing hybrid 3D printers for Sand, foam and ice. We
have initiated EB machine development too. All are funded in PPP.
Conclusions
62