Introduction to Aluminum Use in Automotive1pp2jy1h0dtm6dg8i11qjfb1-wpengine.netdna-ssl.com/... ·...
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Introduction to Aluminum Use in
AutomotiveThe Aluminum Transportation Group
2019 Aluminum Transportation Group
Russ Long
Arconic
Chief Engineer – Ground Transportation Products
Presenter
2019 Aluminum Transportation Group
Day 1 Agenda – Introduction
• Value of lightweighting
• Common automotive aluminum uses
• Potential weight savings
• CAFE overview
• Current BIW and closure applications
• Alloy and temper designations
2019 Aluminum Transportation Group
Day 1 Agenda – Aluminum Sheet Use
• Aluminum sheet production –
flowpath
• Aluminum alloys commonly used for
BIW and closures
• Sheet properties
• Yield, ultimate and elongations as
received
• Properties after paint bake
• Natural aging
• Formability measures
• Joining – spot welding, SPR,
adhesives, flow drill screws, etc.
• Design example – aluminum hood,
aluminum door
2019 Aluminum Transportation Group
Day 1 Agenda – Extrusion Use
• Extrusion process
• Common auto applications
• BIW components
• Bumpers, crash boxes
• Extrusion alloy properties
• T4 versus T6 temper
• Specialty alloys – crush, high
strength for bumpers
• Geometric limitations and guidelines
for extrusion design
• Design example – bumper
2019 Aluminum Transportation Group
Day 2 Agenda – Extrusion Fabrication• Extrusion process (review)
• What is post-extrusion processing?
• Machining
• Joining
• Bending
• Coating
• Summary
2019 Aluminum Transportation Group
Day 2 Agenda – Casting Applications
• Foundry processes and castings evolution
• Casting alloys and designation system
• Foundry metallurgy essentials (101)
• Permanent mold and die casting alloys
• 356.2 series, 354, 355, 357, 359, 413
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Day 2 Agenda – Casting Applications• High integrity aluminum structural die casting
o Conventional vs. high pressure vacuum die castings
o Case study
o Requirements and factors affecting thin wall structural casting
o Properties and tempers F-T4-T5-T6-T7
• Joining
• Modeling
• Stress-engineering strain curves
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Day 2 Agenda – Corrosion and Repair• Introduction
• Objective
• Importance of aluminum surface technologies
• Impact of corrosion in automotive
• Surface influence on several automotive applications and in-service performances
• Factors determining rate of corrosion
• Typical forms of corrosion in automotive body sheets
• Sources of oxidation in aluminum processing
• Methods to control and improve surface quality of aluminum
• Influence of pretreatment on adhesive bonding in automotive joints
• Repair of aluminum panels and BIW parts
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Aluminum Use in AutomobilesAluminum use is growing both in total
weight per vehicle and as a % of curb
weight
Includes all aluminum use (powertrain, BIW,
closures and suspension aluminum)
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Common Uses of Aluminum
Suspension components
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BIW and Closures
2019 Aluminum Transportation Group
Aluminum BIW and closure use increasing and as engines get smaller,
engine block/transmission weight is reduced.
BIW and Closures
2019 Aluminum Transportation Group
Dramatic Weight Reduction Across All Applications
Potential weight savings with aluminum
D-class vehicle
• 10% reduction in curb weight gives a 6% improvement in fuel economy
• Initial OEM focus is on closure panels
• OEMs are developing future aluminum intensive body structures due to greater mass savings potential
• Secondary weight savings are reductions associated with subsystems driven by curb weight (for pass cars — often 25% of primary savings)
• The savings shown will result in a 10-14% curb weight reduction (for ICE vehicles)
Steel (1)
(kg)
Aluminum
(kg)
Typical Wt.
Saving (kg)
%
saving
Hood 16 8 8 50
Fenders 7 3.5 3.5 50
Deck lid 17 9 8 47
Doors 73 43 30 41
BIW 328 209 119 36
Total 441 272.5 168.5 44.870
50 kg
saved
Percentage of BIW + closure weight
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Weight and Size History
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Fuel Economy Regulations – Worldwide
Passenger Vehicle Fuel Economy Fleet Average Passenger Vehicle GHG Emissions Fleet
Average
20
30
40
50
60
70
80
2000 2005 2010 2015 2020 2025 2030
EU
Japan
South Korea
China
US
Solid Lines = Actual Std.
Dotted Lines = Estimated Std.
Conversion factor between fuel economy and CO2 emissions:
• 8887 g CO2 per gallon of gasoline
• 10180 g CO2 per gallon of diesel
MP
G (C
AF
E T
est C
ycle
Norm
aliz
ed)
70
90
110
130
150
170
190
210
230
250
270
2000 2005 2010 2015 2020 2025 2030
Solid Lines = Actual Std.
Dotted Lines = Estimated Std.
G-C
O2/k
m (N
ED
C T
est C
ycle
Norm
aliz
ed)
Regulations only get tougher moving forward
2019 Aluminum Transportation Group
US CAFE Standards are Size Based
How can auto OEMs get to 50 to 60 MPG? I don’t get near this fuel economy with my car!
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
60.0
65.0
35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0
T
a
r
g
e
t
M
P
G
Footprint (square feet)
CAFE Targets for Passenger Cars
2012 Car target
2016 Car target
2017 Car target
2018 Car target
2019 car target
2020 Car target
2025 Café Target
Chrysler 300MalibuCruzeFiesta
2019 Aluminum Transportation Group
US CAFE – Light Truck Targets
What is a light truck?
20.0
25.0
30.0
35.0
40.0
45.0
50.0
55.0
30.0 40.0 50.0 60.0 70.0 80.0
T
a
r
g
e
t
m
p
g
Footprint (sq ft)
Truck CAFE targets
2012 Truck target
2016 truck target
2017 Truck target
2018 Truck Target
2019 truck target
2020 truck target
2025 truck target
F150DurangoGrand
Cherokee
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0 1 2 3 4 5 6 7
Low Friction Lubricants
Engine Friction Reduction
VVT - Dual Cam Phasing (DCP)
Discrete Variable Valve Lift (DVVL) on OHV
Stoichiometric Gasoline Direct Injection (GDI)
Combustion Restart
Turbocharging and Downsizing
Exhaust Gas Recirculation (EGR) Boost
6/7/8-Speed Auto. Trans with Improved Internals
Dual Clutch or Automated Manual Transmission
Electric Power Steering
Improved Accessories
Belt mounted Integrated Starter Generator
Mass Reduction (1.5% of Curb Weight)
Mass Reduction (3.5 to 8.5% of Curb Weight)
Low Rolling Resistance Tires
Low Drag Brakes
Aero Drag Reduction
% Improvement in Fuel Economy
3.5 – 6%
Ref: Corporate Average Fuel Economy for MY2012-MY2016 Passenger Cars
and Light Trucks – Final Regulatory Impact Analysis, NHTSA, March 2010
14 – 25%
5.5 – 9.5%
Drivetrain Alone Cannot Provide the Fuel Savings Required by 2020
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MP
G R
equirem
ents
Multi-material
High Volume Auto Body Evolution
Steel & Aluminum Hybrid(High scrap utilization, Steel to aluminum joining)
Tailoring Products
Aluminum Intensive Vehicle(Strength & ductility for safety, Robust joining)
Aluminum Closures(Increased formability for design/styling)
Evolution of auto design scenarios
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Aluminum BIW are Not New
1922 Ford Model T
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Grumman LLV
US Postal delivery trucks began production in 1987
Vehicle design life was 24 years and
was extended to 30 years in 2009
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Acura NSX
All aluminum – 1990-2005 2016 – present
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Audi Mixed-Material Vehicles
Audi A8
Aluminum since 1994
Audi TT
Aluminum since 2008 (hybrid steel/alum)Audi R8
Aluminum since 2006
Audi Q7 (hybrid steel/aluminum)
Aluminum since 2016
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2016 Audi Q7 – Hybrid Steel/Aluminum
48% steel / 52% aluminum
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Jaguar/Land Rover Aluminum VehiclesAll Jaguar and Land Rover vehicles have aluminum BIW
Jaguar XJ
Aluminum since 2003
Jaguar XE
Aluminum since 2015
Jaguar F-Type
Aluminum since 2013
Range Rover Sport
Aluminum since 1970, 2013
Jaguar F-Pace
Hybrid steel/aluminum
Jaguar XF
Aluminum since 2008
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Range Rover
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Range Rover
Product % of BIW
6xxx sheet 37%
5xxx sheet 37%
Extrusions 6%
Castings 15%
HS Steel 4%
PH Steel 1%
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Ferrari/Lamborghini Aluminum Vehicles
Ferrari 430
Aluminum since 1998
Ferrari 599
Aluminum since 2003
Lamborghini Gallardo
Aluminum since 2003
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Corvette Stingray
Aluminum since 2013
Z series aluminum since 2006
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Tesla Model S Electric VehicleTesla Aluminum Vehicles – All Aluminum
Model S Model X
Model 3
Hybrid steel/aluminum BIW
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Mercedes Benz – All Aluminum Vehicles
Mercedes Benz SL Roadster
Aluminum since 2013
110 kg lighter than steel body
Mercedes Benz AMG SLS Coupe
Aluminum since 2011
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Mercedes Benz C-Class (2014 to present)
24.8% aluminum
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Mercedes Benz S-Class (2013 to present)
32% aluminum
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All Aluminum Ford F-150 – Launched in 2015
Contributes to
CAFE improvement
for first time
America’s best-selling
vehicle for over 40 years
Best in class cargo
performance
700-890lbs lighter
than 2014 steel
model
2019 fuel economy (20/26 mpg) – 2WD 2.7 L Ecoboost (10 speed)
2019 fuel economy (22/30 mpg) – 2WD 3.0 L Diesel (10 speed)
Upgraded to five-star safety rating:
2014 Steel F150
2015 Aluminum F150
2019 Aluminum Transportation Group
2014 Steel F-150 and 2015 Aluminum F-150 Comparison
Steel
2014 F150
(kg)
Aluminum
2015 F150
(kg)
Wt.
Savings
(kg)
% Savings
Hood 10.9 (Alum) 10.6 0.3 3
Fenders 20 7.5 12.5 60
Tailgate 20 9.8 10.2 51
Doors (4) 85 47.6 37.4 44
Cab 283 158 125 43
Cargo Box 105 60 45 43
Total 524 294 231 44
Reference: EuroCarBody 2015, October 21-22, 2015, Bad Nauheim, Germany.
•Ford F-Series is the best-selling
vehicle in America
•2015 F-150 is flagship vehicle
•Super Duty trucks (F-250, F-350,
F-450) also in aluminum
Supercrew with 5.5 ft box
Length = 5890 mm
Wheelbase = 3670 mm
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Steel Ford F-150 and Aluminum F-150 Fuel Economy
37
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Ford Super Duty, Expedition, Lincoln Navigator – All Aluminum
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Cadillac CT6 – Hybrid Steel/Aluminum• 62% aluminum – 38% steel
Includes all aluminum closures
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Chrysler Pacifica
Aluminum hood, sliding doors and liftgate (Mg cast inner)
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2018 Jeep Wrangler
Aluminum hood and doors
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2019 Silverado
Aluminum hood, doors and tailgate
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RAM 1500
Aluminum hood and tailgate
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Daimler Truck
Class 8 Cascadia cab
Aluminum since 1992
Business Class – M2 cab
Aluminum since 2001
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Kenworth and Peterbilt Trucks
Class 8 Kenworth T680 Class 8 Peterbilt 579
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Weight-Sensitive Trailers
Gasoline tankers
Dry bulk trailers
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Weight-Sensitive Trailers
All aluminum flatbeds
Dry van and refrigerated trailers
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Sustainability
Aluminum Is More Sustainable Today
Than Any Other Period In History
of all primary aluminum for automotive applications in North America is smelted in Quebec using
hydropower, resulting in the lowest production carbon footprint for the industry.
More than 75%
Most aluminum automotive parts also contain recycled aluminum, of which the energy demand and carbon footprint is just a tiny
fraction of primary aluminum. Combining these two factors, the production phase emissions of aluminum parts does not increase
when heavier counterparts are replaced. The significant reductions during a vehicle’s driving and end-of-life phases makes
aluminum stand out as the best material to reduce life cycle emissions.
2019 Aluminum Transportation Group
Life Cycle Assessment
A literature review conducted by a team of US EPA researchers on 26 life cycle
assessment (LCA) studies concludes “most of the LCAs demonstrated that
aluminum-intensive designs were able to achieve the largest reductions in life-
cycle energy use and GHG impacts” (Source: Hottle et al 2017).
Several third-party North American LCA studies prove
aluminum’s ability to reduce life cycle energy demand and
GHG emissions of vehicles. Including recent studies
conducted by the Natural Resources Canada (Dubreuil et al
2012), Oak Ridge National Laboratory (Das 2014), Ford
Motor Company & Magna International (Bushi et al 2015)
and Athena Institute (Bushi 2018).
2019 Aluminum Transportation Group
Life Cycle AssessmentReducing vehicle weight with aluminum
increases fuel economy while cutting
both tailpipe and life cycle emissions.
In 2019, the Automotive Science Group found the Ford F-150 holds the
smallest life-cycle carbon footprint of any full-size truck in North America.
The key…automotive aluminum. (Source: The Automotive Science Group)
An aluminum body on a pickup truck can
lower total life cycle global warming
potential and primary energy demand by
7.8 metric tons of CO2 equivalent.
(Source: 2018 EDAG Silverado Body
Lightweighting study)
2019 Aluminum Transportation Group
Recycling
Aluminum can be recycled repeatedly. As a result,
these industry-leading automakers tap into an
endlessly renewable supply of aluminum through
their operations.
Jaguar Land Rover and Ford
Motor Company pioneered closed-
loop recycling of aluminum scrap in their
manufacturing efforts.
Ford’s F-150 manufacturing plants
recycle enough aluminum to produce
At the end of a vehicle’s life, automotive
aluminum is fully and appropriately
recycled and reused for
automotive parts. Two studies conducted by scientists at the
Worcester Polytechnic Institute showed that metal
recovery of automotive aluminum at the end-of-life
recycling is as high as 96% (Source: WPI 2016, 2018)
30,000 new trucks per month.(Source: Ford Motor Company)
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Quiz
1. Open a browser on your laptop, tablet or mobile device
2. Visit: pollev.com/aassociation001
3. Answer the questions based on knowledge from this session.
2019 Aluminum Transportation Group
Questions?
Aluminum Alloy Designations
The Aluminum Transportation Group
2019 Aluminum Transportation Group
Aluminum Alloy Classifications
• Aluminum alloys are categorized by two main groups
• Wrought alloys are further divided into two subgroups
Casting Alloys Wrought Alloys
HEAT TREATABLE
ALLOYS
Their properties
depend on age
hardening
NON HEAT
TREATABLE
ALLOYS
Derive their
properties from
strain hardening
(work hardening)
HEAT TREATABLE
ALLOYS
Properties depend
on age hardening
2019 Aluminum Transportation Group
Some Examples of Alloy-Temper Designations:
1050-O
3003-H24
6111-T4
5052-H32
7075-T6
What does it all mean?
Let’s deal with alloy first….
Alloy Temper
2019 Aluminum Transportation Group
Aluminum Alloy Designation and Nomenclature
• The Aluminum Association system was adopted in 1954
xxxx
1. Alloy group
3. Modification of original
or impurity limits
2. Identification
of alloy, or
aluminum purity
2019 Aluminum Transportation Group
Aluminum Alloy Designation and Nomenclature
1xxx at least 99.00% aluminum (Al)
2xxx main alloying element is copper (Cu)
3xxx main alloying element is manganese (Mn)
4xxx main alloying element is silicon (Si)
5xxx main alloying element is magnesium (Mg)
6xxx main alloying elements are magnesium AND silicon (Mg and Si)
7xxx main alloying element is zinc, Zn (usually also magnesium, Mg)
8xxx alloyed with other elements (e.g. Fe, Li)
xxxx
Non-heat treatable alloys
Heat-treatable alloys
The ‘catch all’ (mainly NHT, but some HT alloys also)
1. Alloy group
2019 Aluminum Transportation Group
Aluminum Alloy Designation and Nomenclature
2. Identification or
aluminum purity
xxxx
For the 1xxx alloys (>99.00% Al) these
two digits tell you the purity of the alloy.
The digits are the minimum Al content
above 99%, examples:
1050 Al > 99.50%
1100 Al > 99.00%
1230 Al > 99.30%
For all the other alloys (non-1xxx) these
two digits identify the alloy within the main
alloy series, i.e. within 2xxx, or 3xxx, etc.
Generally arbitrarily assigned (although
some alloys inherited the 2-digit alloy
identifications existing prior to the
Aluminum Association system adopted in
1954 : 52S → 5052, 24S → 2024)
2019 Aluminum Transportation Group
Aluminum Alloy Designation and Nomenclature
3. Modification of original
or impurity limits
xxxxThe first generation of the alloy is assigned the digit ‘0’
Example: 5083
The first modification of the alloy accepted by the Aluminum
Association as being a substantive variation of the base alloy is
assigned the digit ‘1’ Example: 5183
The next modification to the base alloy is assigned the digit ‘2’
and then the next again is assigned ‘3’ and so on: Examples:
5283, 5383, etc.
Note: If a variant of an alloy is not used for many years, it can
be discontinued, and removed from the ‘Teal Sheets’
2019 Aluminum Transportation Group
Aluminum Association ‘Teal Sheets’
2019 Aluminum Transportation Group
Why So Many Alloys?
• Aluminum Alloy Development
• Answer: “Suitability for use”• Strength
• Formability
• Corrosion resistance
• Toughness
• Etc…
• Pure/commercially pure aluminum (1xxx) has many attractive properties and is used in many applications, but we add elements (alloying) to enhance properties, especially strength
• Blending the mixture of added elements (‘alloying’) can furnish the optimum combination of properties for the application (further enhanced by processing)
2019 Aluminum Transportation Group
AA Temper Definitions
1050-O
3003-H24
6111-T4
5052-H32
7075-T6
Temper
2019 Aluminum Transportation Group
AA Temper Definitions
Heat Treatable Alloy: “T” - tempers
“An alloy which may be strengthened by a suitable thermal treatment” 2xxx, 6xxx, 7xxx are heat-treatable. Examples: 2024-T3, 6061-T6
Non-Heat Treatable Alloy: “H” - tempers“An alloy which can be strengthened only by
cold work” 1xxx, 3xxx, 5xxx, and some 8xxx are non-heat-treatable.
Examples: 3003-H19, 5052-H32
2019 Aluminum Transportation Group
Basic Temper Designations
F As-Fabricated (e.g. as-hot rolled, as-cold rolled)
O Fully Annealed
Hxx Strain-Hardened(NHT wrought products only)
W Solution Heat-Treated (HT) and quenched (unstable)
Tx Thermal Treatment (HT)
F, O, and W are single digit temper designations, e.g.
6061-O, 7075-W, 3004-F
The H and T tempers have two or three further digits
(and sometimes more) to describe the temper
2019 Aluminum Transportation Group
Aluminum Alloy Temper Nomenclature:
Non-Heat-Treatable AlloysMost of these temper designations are in the form:
Hxx
Strain hardened temper
Condition
1 = Strain hardened only
2 = Strain hardened and partial annealed
3 = Strain hardened and stabilized
4 = Strain hardened and lacquered or painted
Strength level
2 = Quarter hard
4 = Half hard
6 = Three quarters hard
8 = Full hard
9 = Extra hard
2019 Aluminum Transportation Group
Heat Treat Temper Designations
F As-Fabricated
O AnnealedH Strain-Hardened
(wrought products only)
W Solution Heat-Treated and QuenchedT Thermal Treatment
(Excluding F, O, or H)
2019 Aluminum Transportation Group
The ‘T’ Tempers• T1 cooled from an elevated temperature shaping process and naturally aged to a substantially
stable condition.
• T2 cooled from an elevated temperature shaping process, cold worked, and naturally aged to a substantially stable condition.
• T3 solution heat-treated, cold worked, and naturally aged to a substantially stable condition.
• T4 solution heat-treated and naturally aged to a substantially stable condition.
• T5 cooled from an elevated temperature shaping process and then artificially aged.
• T6 solution heat-treated and then artificially aged.
• T7 solution heat-treated and overaged/stabilized.
• T8 solution heat-treated, cold worked, and then artificially aged.
• T9 solution heat-treated, artificially aged, and then cold worked.
• T10 cooled from an elevated temperature shaping process, cold worked, and then artificially aged.
e.g. Tx51 Stress-relieved by stretchingOther digits may be added to signify additional processing:
2019 Aluminum Transportation Group
OEM Specific Designations
• Most Auto OEMs purchase to one of their internal specifications
• For example: Ford
Ford
Spec
Typical Application AA Designation
6EH 6xxx outer panel with enhanced
hemming
6022, 6014
6DR1 6xxx exterior or interior 6022, 6016
6HS2 6xxx high strength 6111
6ST1 Alternative high strength 6061
5HF 5xxx High form 5182
5ST 5xxx standard 5754
2019 Aluminum Transportation Group
OEM Specific Designations• Most Auto OEMs purchase to one of their internal specifications
• For example: GM
GM Spec Typical Application AA Designation
Al-S-6000-S-90 6xxx exterior panel 6022, 6014
Al-S-6000-IBR-100 6xxx exterior panel – improved paint bake 6022, 6016, 6451
Al-S-6000-IH-90 6xxx exterior enhanced hemming 6014, 6016, 6022
Al-S-6000-HS-115 Alternative high strength 6111
Al-S-6000-R-110-U 6xxx reinforcement 6022-T4, 6016-T4
Al-S-5000-S-110 5xxx High form 5182
Al-S-5000-RSS-100 5xxx High form – reduced stretcher strain 5182
Al-S-5000-ST-90-90 5xxx Standard 5754, 5454
2019 Aluminum Transportation Group
Aluminum Design Manual
• The aluminum design manual has useful information for design
• It is not set up for automotive design and does not include the alloys we have been discussing, it includes:
• General bearing strengths,
• Methods of calculating design allowables
• Filler alloy selection guide
• Typical welded joint strengths
• Quick fatigue guides
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AA Design Manual – Additional Property Information
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AA Design Manual – Selection of Weld Filler Alloys
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AA Design Manual – Local Buckling Allowables
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Allowable Stresses
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Minimum Bend Radii
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To Convert from Steel to Aluminum:
To Match Bending Stiffness:• Since Modulus of aluminum is 1/3 of steel
Ialum = 3 Isteel
In most cases, the moment of inertia of aluminum parts can be roughly 2.5 Isteel.
When was the last time you upgauged a steel part to reach a stiffness requirement?
To Match Bending Strength:Salum sy alum = Ssteel sy steel
Salum = Ssteel (systeel/ sy alum)
• Density is 1/3, so significant weight savings are possible
2019 Aluminum Transportation Group
X
Y
Ixx = (1/12)*((bd^3-b1d1^3))
Iyy = (1/12)*((db^3-d1b1^3))
dd1
b1
bA = bd – b1d1
Remember minor changes in section size can yield big gains
2019 Aluminum Transportation Group
Simple Example
88
X
Y
d
b
X
Y
d
bSteel Aluminum
b = 60 mm
d = 40 mm
t = 2 mm
Ixx = 102272 mm4
Iyy = 193152 mm4
b = 60 mm (hold because of
packaging)
d = 50 mm (To increase stiffness –
target 2x)
t = 3 mm
Ixx = 241672 mm4 (2.36 x Steel)
Iyy = 322632 mm4 (1.67 x Steel)
Weight Savings = 45%
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Rocker Example
89
Steel T=1.0 Aluminum T=2mm
168.3
89.3
Moments of Inertia Ixx = 2360195 mm4
Iyy = 668175 mm4
178.3
91.3Moments of Inertia Ixx = 5184127 mm4 (2.19 Ixx steel)Iyy = 1451793 mm4 (2.17 Ixx steel)Weight savings = 35%
Moments of Inertia (Centroidal)Ixx = 5826014 mm4 (2.47 Ixx steel)Iyy = 1835972 mm4 (2.75 Ixx steel)
Aluminum T=2.5mm
2019 Aluminum Transportation Group
Roof Rail Example
90
Steel T=1.0 Aluminum T=1.5 mm
72.5
50
78.5
60Moments of Inertia (Centroidal)Ixx = 171111 mm4
Iyy = 90610 mm4 Moments of Inertia (Centroidal)Ixx = 327830 mm4 (1.92 Ixx steel)Iyy = 219817 mm4 (2.42 Iyy steel)Weight savings = 45%
2019 Aluminum Transportation Group
Questions?
2019 Aluminum Transportation Group
Tell Us How We Did!
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