advanced high strength steels2
DESCRIPTION
Presentation provided for non-technical audiences, which may be interested in steel research.TRANSCRIPT
Building Lighter Cars with Advanced High-Strength
SteelsCharles Lester
Georgia Institute of TechnologySchool of Materials Science and Engineering
3/15/2011
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Automotive Applications of Steel Motivation for Improvement in the
Automotive Industry Desirable Attributes of Steel Wheel
Materials Strengthening Mechanisms Why Now? Current Research Summary
Overview
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ArcelorMittal; http://www.arcelormittal.com
Applications
Locations of Steel Components
Rear Cross-MemberWheel Pillar
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Fuel Efficiency
1400 1600 1800 2000 2200 2400 2600 2800 30000
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10
15
20
25
Weight of Vehicles (Kg)
10
-15
Mod
e F
uel
Mileag
e (
Km
/lit
er)
Physical Metallurgy of Modern High Strength Steels, ISIJ International , Vol. 41 (2001), pp.520-532
Motivation for Improvement
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Fuel Efficiency Aesthetics
◦ Create complex shapes
New Microalloyed Steel Applications for the Automotive Industry, Materials Science Forum, pp87-96
Motivation for Improvement
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Fuel Efficiency Aesthetics
◦ Create complex shapes Manufacturing
Considerations◦ Welding different parts
together◦ Ability to form parts using
conventional methods◦ Cost
MachineDesign.com; http://machinedesign.com/article/cranking-out-wheels-0807
Motivation for Improvement
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Shackleford, J., Introduction To Materials Science for Engineers, pp. 193
Mechanical Attributes
Strain
Stress
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Shackleford, J., Introduction To Materials Science for Engineers, pp. 193
Desirable Attributes
Strain
Stress
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1. Solid solution hardening◦ Putting extra material into iron
2. Precipitation hardening◦ Letting material fall out of iron
3. Grain refinement◦ Making the Iron particles smaller
4. Work hardening◦ Applying a load to the iron
Strengthening Mechanisms
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Control of the process has improved◦ Computer control◦ Temperature control◦ Microalloying
Material can be added in precise amount
Why Now?
Current Research
Solid Solution Hardening Precipitation Hardening
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Motivation for steel research◦ Fuel Efficiency◦ Aesthetics◦ Effective Manufacturing
Maximize the absorbed energy Effective strengthening mechanisms Better Processing
Summary
Lighter Steels = Better Fuel Mileage
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Questions