Driven by the need to improve fuel economy and reduce carbon emissions, the automotive industry has focused on developing Electric-drive vehicles (EDVs) as well as the lightweighting of vehicles. This increasing trend has been supported by major manufacturers such as Ford and Tesla. However, with any change in technology new challenges develop. Thermal Management of these vehicles is a large challenge, along with the need to structurally hold the components in place.

1. #DWwebinar

2. #DWwebinar
The Advantages of Using Extrusions to
Solve Thermal Management Challenges for
the Automotive Industry

3. #DWwebinar
 This webinar will be available afterwards at
www.designworldonline.com & email
 Q&A at the end of the presentation
 Hashtag for this webinar: #DWwebinar
Before We Start

4. #DWwebinar
Mary Gannon
Moderator
Design World
Stephen Jackson
Business Development
Mgr., TM Products
Sapa Extrusions NA
The Advantages of Using Extrusions to Solve Thermal Management
Challenges for the Automotive Industry

5. ADVANTAGES OF USING EXTRUSIONS
IN THE AUTOMOTIVE INDUSTRY TO
SOLVE THERMAL MANAGEMENT
CHALLENGES
JASON WEBER & STEVE JACKSON
NOVEMBER 3, 2015

6. ADVANTAGES OF USING EXTRUSIONS IN THE AUTOMOTIVE
INDUSTRY TO SOLVE THERMAL MANAGEMENT CHALLENGES
AGENDA
Who is SAPA
Why Aluminum to Lightweight Vehicles and EV’s
Designing Thermal Extrusions
Extrusions versus Castings
Friction Stir Welding (FSW) of Extrusions
Module Heat Sinks
Extruded Cold Plates
Summary

7. SHAPING A SUSTAINABLE FUTURE THROUGH INNOVATIVE
ALUMINUM SOLUTIONS
Precision tubing
Profile-based building
systems
Value-added profiles

8. Present in40countries
100+ production units
5 business areas:
Profiles Europe, Profiles Americas, Profiles
Asia, Buildings System, Precision Tubing
~$8.5 billion sales Worldwide
$2.4 billion sales America’s
SAPA IN FIGURES
World leaderin aluminum solutions
23,000employees worldwide, 6,500 in Americas
* 2011 pro-forma

9. GLOBAL APPLICATION DEVELOPMENT
Sapa Extrusions’ central product development resource. The team
supports customers and regional Sapa resources in developing innovative
solutions and products.
Key competencies
 Aluminum Extrusions
 Product Design & Optimization
 Simulation & Analysis
 Project Management
 Technology & Knowledge
Transfer
Product expertise
 Renewable Energy
 Thermal Management
 LED Thermal Solutions
 Marine
 Engineered Products

10. LOCAL PRESENCE, AROUND THE WORLD

11. SAPA IN NORTH AMERICA
Yankton, SD
Portland, OR
City of Industry, CA
Spanish Fork, UT
Burlington, NC
Connersville, IN
Mountain Top, PA
Mississauga, ON
Montreal, QC
Elkhart, IN Cressona, PA
Gainesville, GA
Delhi, LA
Phoenix
St. Augustine
Sidney, OH
Kalamazoo
North Liberty, IN
Belton
Toronto, ON
Magnolia, AR
Monett, MO

12. Sapa shall offer the market innovative, value-enhancing solutions based on
profiles and strip in the “green” and lightweight material aluminum.
Sapa shall be perceived as the most attractive partner through a
combination of innovation, business know-how and cost effectiveness.
OUR MISSION & VISION

15. HYBRID THERMAL MANAGEMENT
E-Vehicle thermal
management
LED Lights
Capacitor Housing
(Thermal & Structural)
(Thermal)
(Structural)
(Thermal & Structural)
(Thermal & Structural)
(Thermal & Structural)

16. ALUMINUM EXTRUSIONS
Material Advantages Process Advantages
Recyclable & Non-toxic
Lightweight
Strong
Corrosion resistant
Thermally conductive
Reflective
Electrically conductive
Non-magnetic
Non-sparking
Attractive
Finish Options
Virtually Seamless
Complex integral shapes
Easily assembled
Weldable
Machinable
Cost-effective
Short lead times

17. WHY COOLING ? HEAT IS THE ENEMY OF ELECTRONICS
Performance: Functional operation of device
Reliability: Temperature dependency of failures
Integrity: Structurally sound and mechanically strong
HEAT is the ENEMY of Electronics
Lack of Strength is the ENEMY of Shock & Vibration
Cost is the ENEMY of Everyone
Aluminum Extrusions can be the SOLUTION

18. ALUMINUM EXTRUSION SOLUTIONS
Aluminum Extrusions for Air Cooling
Modular Heat Sinks for High-Fin Ratio requirements
Liquid cooler for power electronics (IGBT, control unit, inverters,
converters) and electric motors
Battery enclosures for structural & thermal management
Light-weight parts to light-weight the vehicle

19. THERMAL CONDUCTIVITY OF ALLOYS
Thermal conductivities
0
50
100
150
200
250
pure aluminium extrude Al-alloys cast Al-alloys
thermalconductivity,W/mK
Thermal conductivities:
Diamond is the best, 2,300 W/mK
Too expensive
Copper (pure): 390 W/mK (much heavier
and more expansive)
Pure aluminium: about 230 W/mK
(difficult to extrude)
Extruded alloy AA6063: about 200 -215
W/mK
Cast aluminum alloys: about 120-140
W/mK

20. TYPICAL HEAT SINKS

21. COMPUTER SIMULATION
Basic study on heat sinks
Heat sink optimisation (geometry)
Customers specified simulation
Development of own rapid calculation program
Design for Manufacturability
Evaluation of cost factors

22. Developing the most effective heat sink solutions through the use of
CFD/FEM computer simulations.
Sapa developed software for
designing and optimizing air cooled
heat sinks.
TECHNICAL EXPERTISE IN THERMAL DESIGN

23. PROFILE DESIGN

24. PROFILE DESIGN

25. FAN CURVE AND WORKING POINT:
Fan working point:
Air flow: 0.91 m3/sec (for 4
heat sinks)
Total press-drop: 670 Pa
Air flow per heat sink:
0.23 m3/sec or 820 m3/hour
Pressure drop over heat
sink:
520 Pa (670-150=520)

26. CFD EXAMPLE
20 W
33 W
33 W
3x20 W
4x62.5 W

27. COMPARISON OF TWO DESIGNS

28. Thermal testing setup:
LABORATORY TESTING OF COMPUTER DESIGN
Over-temperature, measurement vs. calculation (SapaCool)
10,0
15,0
20,0
25,0
30,0
35,0
40,0
45,0
0 10 20 30 40
air flow, m3/hour
over-temperature
1.15 measure
1.15 calculation
0.7 measure
0.7 calculation

29. PROFILE DESIGN
What is the goal?
Design the optimal profile that fulfills the demands of the application
at the lowest possible cost.
To design the optimal profile, we must understand factors in production
that increase costs.

30. Fin height to gap ratio is typically limited to 16:1
Example of 7.5:1

31. TOOLING COST FACTORS
Die Breakage
Alloy
Profile type and circle size
Non-fill condition
Thin walls or sharp corners
Thick to Thin Ratio (variable
bearings)
Tolerance requirements

32. PRODUCT DESIGN COST FACTORS
Type of Profile
Solid
Semi-Hollow
Hollow
Fin Ratio
> 6:1; >12:1
Wall Thickness
Thin? Thin to Thick?
Tolerances
Standard AA vs. Tighter
Cut Length
Long Lengths vs. Short
Lengths
Flatness
Fly-cut
Fabricating
How many directions
Surface Finish
Anodize? Paint?

33. PROFILE CLASSIFICATIONS
Solid
Low production cost
Low die cost
Semi-Hollow
Tooling could break sooner
Higher material and die cost
Hollow
Higher Material and Tooling Cost
Multi-Void hollows have the highest
cost

34. CIRCLE SIZE DIAMETER

35. GEOMETRY OPTIMIZATION

36. DIFFICULT, MULTI-HOLLOW SHAPES

37. PROFILE DRAWING

38. DAMAGED DIE

39. EXTRUSIONS VERSUS CASTINGS
The vast majority of heat sinks are extrusions or castings
Depending on the criteria and requirements, either can work
Volume and budget are large factors in making the decision

40. Thermal
Conductivity
Lack of
Porosity Near Net Shape
Tooling
Costs Piece Part Price
Secondary
Machining
Required Design
Extrusion 1 1 2 1 2 2 2-Dimensional
Die Casting 3 2 1 5 1 1 3-Dimensional
Permanent Mold Casting 4 4 3 3 3 3 3-Dimensional
Sand Casting 5 5 4 2 5 4 3-Dimensional
1 = Best, 5 = Worst
Not all castings are the same
Do you need a three dimensional solution
Will the design change?
Can the design accept draft angles required for castings?
Is surface finish important?

41. EXTRUSION ALLOY VS. DIE-CAST ALLOY

42. TEMPERATURE:
23% REDUCTION OF MAX TEMPERATURE
Existing design (Die
Cast)
Sapa’s proposed design (Extrusion)
Notice the difference in temperature only through changing the shape of the fins
THERMAL ANALYSIS OF EXTRUSION VS. CASTING

43. PROFILE DESIGN

44. WHAT IF THE RATIO IS TOO BIG TO EXTRUDE?

45. WHAT IF THE FINAL WIDTH IS TOO WIDE TO EXTRUDE?

46. HISTORY
Invented and patented by the Cambridge, England based The
Welding Institute (TWI) in 1991.
Sapa, the largest aluminum extruder in Europe, played an active part
in the process of converting theory and laboratory experiments into
full scale production.
In 1996, Sapa started series production in the railway and marine
industries.
FRICTION STIR WELDING

47. DEFINITION
FSW is a method of joining two pieces of metal with no filler material by
subjecting the components to heavy plastic deformation, at high
temperatures, but lower than the melting point.
FRICTION STIR WELDING

48. PROCESS
A rotating tool is plunged into the components and friction heat is generated.
The tool produces severe plastic deformation under high pressure, at which
time the weld interfaces are stirred together and a homogenous structure is
formed.
FRICTION STIR WELDING

49. METHOD
FRICTION STIR WELDING

50. WELD STRUCTURE
Fully re-crystallized fine grain micro-structure is created in the nugget by the
intense plastic deformation at elevated temperature.
FRICTION STIR WELDING

51. TIG WeldingMIG Welding
FRICTION STIR WELDING

52. Compared to Fusion Welding, Friction Stir Welding provides:
Increased strength (High tensile, fatigue & bend properties)
Improved sealing, completely void-free leak proof joints
Reduced thermal distortion and shrinkage
Improved repeatability
The ability to join two different alloys
Suitable for automation
No filler metal (parent metal thermal conductivity)
Cost effective
FRICTION STIR WELDING

53. MECHANICAL PROPERTIES
*MATS ERICCSSON AND ROLF SANDSTROM AT THE ROYAL INSTITUTE OF TECHNOLOGY
6082 T6 Aluminum Yield Strength (MPa) Tensile Strength (Mpa) Elongation (%)
Min specification for profile, 5mm 250 295 6
Actual Specimen 291 317 11.3
Pulsed MIG 147 221 5.2
TIG 145 219 5.4
FSW 150 245 5.7
FRICTION STIR WELDING

54. WIDE EXTRUSIONS:
7” Circle Size is the most common width of extrusions
21” circle sizes are available, but expensive
With proper design, there is no limit to the width of a FSW extrusion
FSW can penetrate the surface as deep as 20 mm
The base provides an efficient thermal path to remove the heat.
FRICTION STIR WELDING

55. FRICTION STIR WELDING

56. This process is usually performed on FSW equipment up to thirty feet
long
FRICTION STIR WELDING - CONSISTENTLY ENABLING STRONGER, MORE
EFFICIENT STRUCTURES

57. Renewable Energy (aka Battery) Housings:
Super Capacitors are being used to store energy for hybrid and electric vehicles. The
capacitors are usually held together via a housing. Thermal management has been a
challenge for these, however FSW extrusions are a proven solution. They provide:
Thermal Efficiency
Custom Shapes
Tight fit to capacitor
Structural integrity
Low start-up costs
FRICTION STIR WELDING

58. FRICTION STIR WELDING

59. FRICTION STIR WELDING

60. Another use of FSW has been in the lighting industry where specialized lights
are required to be sealed from the atmosphere. Sapa has successfully friction
stir welded an aluminum extruded hollow heat sink to a casting end cap to
provide a complete seal.
FRICTION STIR WELDING

61. MOTOR HOUSINGS

62. BONDED FINS:
Definition: Joining an aluminum extrusion or plate to a sheet of
aluminum via a thermal epoxy.
Challenges: Manual operation, thermal interference
FRICTION STIR WELDING

63. SOLUTION: Sapa FSW Module Heat Sinks
Ratios up to 40:1
8% more thermally efficient than comparable bonded fin heat sinks
Automated process
Custom solutions possible
FRICTION STIR WELDING

64. FSW Bonded
FSW Heat sink vs. bonded fin heat sink:
FRICTION STIR WELDING

65. THERMAL RESISTANCE:
The thermal resistance of FSW modular heat sink is 8% lower than
bonded fin design.
*THE DEFINITION OF THERMAL RESISTANCE:
FRICTION STIR WELDING

66. LIQUID COOLING
Typical Definition: Copper pipes thermally glued to aluminum plate,
than vacuum brazed
Challenges: Rising price in copper, manual process, lengthy process
Sapa Solution: FSW cold plates with extruded “pipes”
FRICTION STIR WELDING

67. METHOD
The liquid cooler is sealed by friction stir welding the lids to the
extruded body.
FRICTION STIR WELDING

68. *PATENTED BY SAPA
EXTRUDED LIQUID COOLER*
FRICTION STIR WELDING

69. 69
METALLOGRAPHIC EXAMINATION
PRESSURE TEST
The liquid cooler can withstand burst pressure up to 90 bar.
FRICTION STIR WELDING

70. LIQUID COOLING: COMPARISON OF TWO DESIGNS
Heat source
30
Heat source
15
199

71. LIQUID COOLING: TEMPERATURE & FLOW
Design No.2Design No.1

72. LIQUID COOLER (COLD PLATE) FOR COOLING OF ELECTRONICS IN
HEV

73. Thermal
Performance
- Alloy selection
- Fin design/spacing
- Heat sink orientation
- Surface treatment
- CFD Analysis
Extrusion
Design
- Weight reduction
- Profile functionality
- Space limitations
- Best practice mfg.
Efficient
cost
effective
solution
SUMMARY OF ALUMINUM EXTRUSIONS & FSW
FRICTION STIR WELDING - CONSISTENTLY ENABLING STRONGER, MORE
EFFICIENT STRUCTURES

74. #DWwebinar
The Advantages of Using Extrusions to Solve Thermal Management
Challenges for the Automotive Industry
Stephen Jackson
Business Development Mgr., TM Products
Sapa Extrusions NA
Stephen.jackson@sapagroup.com
Questions?
Mary Gannon
Senior Editor – Moderator
Design World
mgannon@wtwhmedia.com

75. #DWwebinar
Thank You
 This webinar will be available at
designworldonline.com & email
 Tweet with hashtag #DWwebinar
 Connect with Design World
 Discuss this on EngineeringExchange.com

76. #DWwebinar