LIGHTFAIR International 2018 Provider Number - Z136

The Value of 3-D Printing in Manufacturing Solid-State Lighting SystemsL18SM07

N. Narendran, I.U. PereraMay 9, 2018

Credit(s) earned on completion of this course will be reported to AIA CES f AIA b C ifi f

for continuing professional education. As such, it does not i l d h b d dCES for AIA members. Certificates of

Completion for both AIA members and non‐AIA members are available upon request

include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or anyupon request. material of construction or any method or manner ofhandling, using, distributing, or dealing in any material or product.dealing in any material or product.___________________________________________Questions related to specific materials, methods, and services will be addressed at the conclusion of this

This course is registered with AIA CES

services will be addressed at the conclusion of this presentation.

This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written

Copyright Materials

p , , p y ppermission of the speaker is prohibited.

© LIGHTFAIR International 2018

CourseDescription

The explosion of solid‐state lighting (SSL) products in the market and their price erosion has necessitated the search for lower cost materials and manufacturing methods. The automotive, aerospace,materials and manufacturing methods. The automotive, aerospace, and medical industries have recently embraced 3‐D printing for manufacturing, a solution that also could allow the lighting industry to offer lower cost, custom SSL systems that are produced on‐site to achieve on‐time and on‐demand manufacturing. This course will describe current 3‐D printing technologies and materials and whether they can be used to manufacture the thermo‐mechanical, electrical, and optical components necessary for SSL fixtures.

LearningObjectives

At the end of the this course, participants will be able to:

1. Learn about current 3‐D printing technologies and materials and how 3‐D printing of lighting components works

At the end of the this course, participants will be able to:

3 D printing of lighting components works

2. Learn about recent research into the thermal conductivity of 3‐D printing polymers and their ability to create LED heat sinks

3. Learn about using 3‐D printing inks to create electrical traces for solid‐state lighting

4. Learn about possible 3‐D printing technologies for creating optical components

The Value of 3‐D Printing in ManufacturingThe Value of 3 D Printing in Manufacturing Solid‐State Lighting Systems

May 9, 2018 – 8:30 am

N d j h N dNadarajah NarendranIndika Perera

Lighting Research Center, Rensselaer Polytechnic InstituteLighting Research Center, Rensselaer Polytechnic Institute

33‐‐D printingD printing• Objects are fabricated by

depositing material layer by layerlayer

• Also known as additive manufacturing (AM)

S l t f 3 D i tihttps://3dprinting.com/what‐is‐3d‐printing/

• Several types of 3‐D printing processes

7

Most common 3Most common 3‐‐D printing processesD printing processes1. Thermoplastic extrusion process

– Fused deposition modeling (FDM)2 V t h t l i ti2. Vat photopolymerization process

– Stereolithography (SLA)– Digital Light Processing (DLP)Digital Light Processing (DLP)

3. Powder bed fusion process– Selective Laser Sintering (SLS)g– Multi‐jet fusion– Direct Metal Laser Sintering (DMLS)– Selective Laser Melting (SLM)– Electronic Beam Melting (EBM)

4 M i l Bi d j i

8

4. Material or Binder jetting

Most common 3Most common 3‐‐D printing processes D printing processes

1 2 3 4

Source: 3dhubs.com

9

33‐‐D Printer ManufacturersD Printer ManufacturersPrinting technology Printer Manufacturers

Thermoplastic extrusion XYZprinting, Stratasys, 3DSystems UltiMaker3DSystems, UltiMaker, Markforged

Vat photopolymerization Formlabs, 3DSystems, Carbon, B9Creator

Selective laser sintering, M lti j t f i

3DSystems, EOS, SINTERIT, hpMulti‐jet fusionDirect metal laser sintering, Selective laser

EOS, GE (Concept Laser and Arcam), 3DSYSTEMS, SLM g,

melting, and Electron beam melting

), ,Solutions

l d b d h

10

Material and binder jetting

Stratasys, 3DSystems, hp,ExOne, Rize, XAAR,

33‐‐D Printer Material ManufacturersD Printer Material ManufacturersPrinting technology Material ManufacturersThermoplastic extrusion BASF, ARKEMA, Covestro,

M kf d St t P tMarkforged, Stratasys, Proto‐pasta, colorFabb

Vat DSM, Dow Corning, Henkel, Vatphotopolymerization

SM, ow Corning, Henkel,SARTOMER (ARKEMA),3DSystems,

Direct metal laser sintering, Selective laser melting, and Electron

ATI Powder Metals, SANDVIK Osprey, Renishaw, Metco, Praxair, GKN Hoeganaes, g,

beam melting, g ,

Materialise

Selective laser sintering, ARKEMA, BASF, Covestro,

11

Material jetting, and Binder jetting

Evonik, OPM

Expanding Market for 3Expanding Market for 3‐‐D PrintingD Printing• Industries that have embraced 3‐D printing for

manufacturing parts and systems – Automotive– Automotive – Aerospace – Medical– Consumer products

12

Reasons for pursuing 3Reasons for pursuing 3‐‐D printing today D printing today • Prototyping

P d t d l t• Product development

• CustomizationCustomization

• Innovation

• Reduce stocked inventory

13

Source: 3D printing: The next revolution in industrial manufacturing, UPS and Consumer technology Association, 2016

33‐‐D Printing Market Size D Printing Market Size • 3‐D printing industry is expected to grow to more

than $21 billion in revenue by 2020.

https://www.computerworld.com/article/3066862/emerging‐technology/3d‐printing‐i d i l i f 21b h l

14

industry‐to‐triple‐in‐four‐years‐to‐21b.html

CanCan SolidSolid StateState LightingLighting BenefitBenefitCan Can SolidSolid‐‐StateState‐‐Lighting Lighting Benefit Benefit from from 33‐‐D printing? D printing?

15

LED Luminaire Market Size LED Luminaire Market Size • LED luminaire market size is projected to reach $45

billion by 2022.

http://www.ledsmagazine.com/articles/print/volume‐14/issue‐5/features/strategies‐in‐light‐2017/market‐outlook‐brightens‐for‐leds‐with‐new‐ssl‐applications‐emerging.html

Philip Smallwood, Strategies in Light 2017

16

Price Erosion for LED Lighting FixturesPrice Erosion for LED Lighting Fixtures• Industry trend

– LED lighting fixtures are manufactured overseas and shipped to U Sand shipped to U.S.

• Commodity (low cost)• Increased carbon footprint p

• Lighting trends for 2018– Lighting fixtures with more functionality

• will have sensors, radios for wireless connectivity, processors for increased intelligence to conserve energy or deliverintelligence, to conserve energy or deliver tailored light, etc. (IoT ready)

• 3‐D printing could further add value

17

– custom lighting fixtures, made on‐site, on‐demand

Why 3Why 3‐‐D printing for SSL fixtures?D printing for SSL fixtures?• Today: Prototyping (form factor only)• Potential benefits if complete fixtures can be printed

in the futurein the future– Custom fixtures

• Improved visual appeal and functionsp pp– Reduced fixture cost

• Heat sinks with tailored thermal properties• Print and assemble optics (one‐step) • One‐step process for all components • Reduce stored inventory of systems and parts

– Reduced carbon footprint: • Manufacturing on site (3 D printing)

18

• Manufacturing on‐site (3‐D printing)

33‐‐D printing for LightingD printing for Lighting• Some lighting companies are

already exploring the benefits of AM for lighting

Philips Lighting Telecaster: Philips New Venture for 3D Printed Architectural Lightingof AM for lighting

Repro‐light Consortium aims

http://www.3dprinting.lighting/

Repro light Consortium aims to Revolutionize the Lighting Industry by 2020

19

Vision for SSL and 3Vision for SSL and 3‐‐D PrintingD PrintingChange Architectural Lighting PracticeChange Architectural Lighting Practice

https://commons.wikimedia.org/wiki/File:Edificio_dise%C3%B1ado_para_el_mar.jpg

Fixture design On‐demand, On‐site manufacturing

Custom fixtures

20Credit: Lighting Research Center

Lighting Research Center Studies Lighting Research Center Studies • Goal:

– To investigate if functional thermo‐mechanical, electrical and optical components can beelectrical, and optical components can be fabricated using current 3‐D printing technologies and materials to manufacture complete SSL li h i filighting fixtures

[LRC 2017]

21

[LRC 2017]

Credit: Lighting Research Center Credit: Lighting Research Center

33‐‐D Printing Processes InvestigatedD Printing Processes Investigated

22

Material extrusionMaterial extrusion• Material is selectively

dispensed through a nozzle– Fused deposition modeling– Fused deposition modeling (FDM® [term and abbreviation trademarked b S ])by Stratasys, Inc.]).

– Thermoplastic material through heated extruder

Source: http://www.lboro.ac.uk/research/amrg/about/the7categoriesofadditivemanufacturing/materialextrusion//through heated extruder

Fused filament fabrication (FFF) (Equivalent to FDM)

– Continuous fiber fabrication (CFF)

23

Vat photopolymerizationVat photopolymerization• Produce parts from

photopolymer material in a liquid state cured using either:liquid state cured using either:– Stereolithography (SLA)

• Selectively cure material using lasers

– Digital light processing (DLP)• Cure photopolymerCure photopolymer material using digital light projectors

24

Source: Wallace et al., “Validating continuous digital light processing (cDLP) additive manufacturing accuracy and tissue engineering utility of a dye‐initiator package,” Biofabrication, 2014, 6, 015003

Mechanical Mechanical ComponentsComponents

Mechanical ComponentMechanical Component• Heat sink

– To keep LED junction temperature low D b k H E i O d i d– Drawbacks: Heavy, Expensive, Overdesigned thermal management

26

Estimated Tj for heat sink Estimated Tj for heat sink κκLED heat sink

Parameter Value

LED package

Parameter Value1 ,2, 5, 10W

10°C/W

12.7 mm

10.0 cm

10.0 cm

2.5 mm0.9

20°C

27

Thermal conductivity of aluminum~200 W m-1 K-1

Credit: Lighting Research Center

Study ObjectivesStudy Objectives• To investigate potential use of thermoplastic filament

in 3‐D printing heat sinks for LED applications– To characterize and quantify 3‐D printed– To characterize and quantify 3‐D printed components with commercial filament

• Build orientation and infill percentage– To quantify and compare 3‐D printed heat sinks with aluminum heat sink of similar geometryT i ti t h t i k t ff t LED– To investigate heat sink geometry effects on LED performance

• Temperature profilep p• Temperature gradient

28

Preparation of 3Preparation of 3‐‐D printed test samplesD printed test samples

20.0±0.1 mmCross‐section of

10.0±0.10 mmdeposited materialVoids (air)

L 3

Layer 1 Layer 2 Layer 3

Cross‐planeIn‐planeLayer 1 Layer 2 Layer 3

29

Credit: Lighting Research Center

Methodology and setup for thermal Methodology and setup for thermal characterizationcharacterizationcharacterizationcharacterizationSteady‐state heat equation (Fourier’s law);

Assuming constant heat flux;

Credit: Lighting Research Center

30

Thermal characterizationThermal characterization

Credit: Lighting Research Center

31

Reference: Perera, I.U., N. Narendran, V. Terentyeva. 2018. “Thermal characterization of three‐dimensional printed components for light‐emitting diode lighting system applications” Opt. Eng 57(4),

manuscript in press.

Thermal characterizationThermal characterization• Temperature gradient per

unit length – In‐pane < Cross‐plane– In‐pane < Cross‐plane

• Additives decreased temperature gradient per unit length

• Improvement in material required for comparablerequired for comparable performance to Aluminum heat sinks

Credit: Lighting Research Center

32

Reference: Perera, I.U., N. Narendran, V. Terentyeva. 2018. “Thermal characterization of three‐dimensional printed components for light‐emitting diode lighting system applications” Opt. Eng 57(4),

manuscript in press.

Thermal characterizationThermal characterization• Build orientation along the heat transfer direction• Increased infill percentage decreased temperature

differencedifference – Decreasing thermal resistance in the 3‐D printed sample

33

Thermal performance of heat sinksThermal performance of heat sinks• To understand how composite polylactic acid or

polylactide (PLA) filaments with thermally conductive additives affect thermal conductivity of printed heatadditives affect thermal conductivity of printed heat sinks.

34 Credit: Lighting Research Center

Estimated Tj with different heat sinksEstimated Tj with different heat sinks• Increased thermal conductivity reduces LED junction

temperature– Case temperature is about 20°C lower than Tj– Case temperature is about 20 C lower than Tj

35Reference: Narendran, N., I.U. Perera, X. Mou, and D.R. Thotagamuwa. 2017. Opportunities and challenges for 3‐D printing of solid‐state lighting systems. Proceedings of SPIE 10378, 16th International Conference on Solid State Lighting and LED‐based Illumination Systems, SPIE Optics + Photonics, San Diego, Calif., August 2017, Paper 10378‐35.

Measured material thermal conductivityMeasured material thermal conductivity

Materialκ [W m‐1 K‐1 ] In‐plane

Cross‐lIn‐plane Cross‐plane planeIn plane Cross plane

Generic PLA 0.29 0.22 1.32Copper infused PLACopper infused PLA variant A 0.56 0.42 1.33

Copper infused PLA 0 51 0 40 1 28variant B 0.51 0.40 1.28

Carbon fiber PLA 0.60 0.26 2.31Bronze infused PLA 0 57 0 44 1 30Bronze infused PLA 0.57 0.44 1.30Conductive PLA 0.45 0.31 1.44Graphene infused PLA 0.97 0.50 1.95

36

Copper‐based liquid 1.54 NASilver‐based ink 7.96 NA

Heat sink temperature profileHeat sink temperature profile• Low κ of 3‐D printed heat sinks

had high resistance – From fin base to fin tip 34 mm

28 mm

– From fin base to fin tip– cross‐sectional area temperature gradient < 20°C

34 mm29 mm

9 mm 9 mm

75%100%

Graphene composite PLAAluminum heat sink

60% 50%

C di Li h i R h C

37

Copper composite PLA Generic PLACredit: Lighting Research Center

Credit: Lighting Research Center

Heat sink geometry effectsHeat sink geometry effects• Increase in surface area at the

high temperature region reduced LED case temperaturereduced LED case temperature

Tc=64 °C

Tc=66 °CTc=66 °C

38

Tc=70 °CCredit: Lighting Research Center

Credit: Lighting Research Center

Thermal conductivity of printed partsThermal conductivity of printed parts• Thermal conductivity of 3‐D printed PLA components

depends on build orientation and filler material propertiesproperties – Compared to cross‐plane, the in‐plane thermal conductivity is much better

• 30% to 131% higher– Infill percentage increase increased the thermal conductivity of 3 D printed componentsconductivity of 3‐D printed components

– Graphene‐infused PLA had the highest κ value• Still 20 times smaller

– Need improved performance filaments to meet thermal conductivity needs of heat sinks for LED

39

systems

Electrical ComponentsElectrical Components

Electrical propertiesElectrical properties• Study objective:

– To investigate if 3‐D printed electrical traces haveelectrical traces have suitable electrical properties

• Three types of filamentCredit: Lighting Research Center

– Graphene‐infused PLA– CNT‐infused PLA– Carbon black‐infused PLA

• Three build orientationsParallel to the current flow Current – Parallel to the current flow

– Normal to the current flow 45° angled to the current Voltage

channel

3‐D V

A

41

gflow

Voltage channelprinted

traceCredit: Lighting Research Center

Reference: Narendran, N., I.U. Perera, X. Mou, and D.R. Thotagamuwa. 2017. Opportunities and challenges for 3‐D printing of solid‐state lighting systems. Proceedings of SPIE 10378, 16th International Conference on Solid State Lighting and LED‐based Illumination Systems, SPIE Optics + Photonics, San Diego, Calif., August 2017, Paper 10378‐35.

Results and SummaryResults and Summary• Graphene‐infused PLA filament 6.1×10‐3 Ωm

– Copper traces (1.7×10‐8 Ωm)I l b ild i t ti h d th l t– In‐plane build orientation showed the lowest resistivity

• Inks with resistivity values similar to copper are y ppavailable– Cannot be processed using unmodified FFF‐type 3 D i t3‐D printers.

– Requires paste extruder materials

https://support.voxel8.co/hc/en‐us/articles/208004096‐Working‐with‐the‐Conductive‐Silver‐Ink‐Solvent

Credit: Lighting Research Center42

Optical ComponentsOptical Components

Optical properties of printed componentsOptical properties of printed components• Study objective:

– To investigate if SLA printing and commercially availableand commercially available materials are suitable for printing lenses Before

polishingAfter

polishing

Secondary lens and holder

• Light transmission and scattering as a function of print resolution and print orientation

50 μm

250 μmresolution and print orientation– Resolution: 50 μm and 250 μm print

μ

laser

– Print orientation: in‐plane and cross‐plane

In‐plane

laserR f N d N I U P X M d D R Th t 2017

Cross‐planeCredit: Lighting Research Center

Reference: Narendran, N., I.U. Perera, X. Mou, and D.R. Thotagamuwa. 2017. Opportunities and challenges for 3‐D printing of solid‐state lighting systems. Proceedings of SPIE 10378, 16th International Conference on Solid State Lighting and LED‐based Illumination Systems, SPIE Optics + Photonics, San Diego, Calif., August 2017, Paper 10378‐35.

44

Results and SummaryResults and Summary• Both print resolution and orientation affect light

transmission and scattering distribution – Polishing the 3‐D printed optical elements– Polishing the 3‐D printed optical elements improved performance

– Increased print resolution increased light transmission and decreased light scattering

– In‐plane print orientation had greater light transmission (~3 times) compared to cross planetransmission ( 3 times) compared to cross‐plane print orientation

– Cross‐plane print orientation had greater light scattering compared to in‐plane print orientation

• Requires post‐processing to refine and improve optical performanceoptical performance

45

Final remarksFinal remarks• Opportunities

– Change architectural lighting practicesM t i ti– Mass customization

• ChallengesChallenges– 3‐D printed mechanical, electrical, and optical components cannot be performed on the same platform

– New materials are needed to meet performance needs of SSLneeds of SSL

– Faster printing speed needed to meet application demand

46

AcknowledgmentsAcknowledgments• LRC Faculty, Staff, and Students• LRC internal funding

ASSIST• ASSIST• FAA

l i d / / lidwww.lrc.rpi.edu/programs/solidstate

47

Thank you

Please remember to complete h l ithe course evaluations.

Thank you.Thank you.

48