Integrated Computational Materials Engineering

Lab Heat Results Supporting DOE Targets

Grant Thomas, AK Steel Research

Prof. David Matlock, Colorado School of Mines

Radhakanta Rana, Colorado School of Mines

Louis Hector Jr., Principal Investigator, General Motors

Prof. Fadi Abu-Farha, Clemson University

Project Overview

Timeline:

• Project Start Date: February 1, 2013

• Project End Date: January 31, 2017

• Percent Complete: ~40%

Budget

• DOE Share: $6,000,00

• Contractor Share: $2,571,253

Project Goal:

Create a model for Third Generation Advanced

High Strength Steels (3rd Gen. AHSS)

• Incorporate different length scales

- Integrated Computational Materials

Engineering (ICME)

• Aid development

• Aid application

• Products to market faster

Project Plan

Modeling

Assembly

Predictive

Validation

Performance

This Presentation

Experimental

Department of Energy Targets for 3G AHSS

Yield Strength

(MPa)

Tensile Strength

(MPa)

Total Elongation

(%)

Uniform Elongation

(%)

800 1200 30 20

1200 1500 25 8

Simple Rule of Mixtures Model—Microstructure

D.K. Matlock and J.G. Speer, “Design Considerations for the Next Generation of Advanced High Strength Sheet Steels,” Proceedings of the

3rd Int. Conf. on Structural Steels, ed. by H.C. Lee, Korean Institute of Metals and Materials, Seoul, Korea, 2006, pp. 774-781.

Mixtures of austenite and martensite can give excellent properties.

Meta-Stable Austenite—More Design Opportunity

D.K. Matlock and J.G. Speer, Proceedings of the 3rd Int. Conf. on Structural Steels, The Korean Institute of Metals and Materials, Seoul,

Korea, 2006, pp. 774-781.

Mixtures of meta-stable austenite and martensite

may have the potential to reach DOE targets.

Austenite

Stability

Conditions

Many Paths to 3rd Generation AHSS

Tensilized SS

Med. Mn Lower $$

TWIP

D.K. Matlock , J.G. Speer, R. Radhakanta, E. De Moor, ICME Kickoff Meeting, SMDI, Southfield, MI, DOE#: DE-EE0005976, March 12, 2013

Enhanced

PHS

Q&P

Enhanced,D

P, TRIP

Med. Mn

Q&P

MEDIUM MANGANESE STEEL

Laboratory Results from Experimental Heats of

1 m

Intercritical Annealing—Mn Partitioning

P. Gibbs, Ph. D. Thesis, Colorado School of Mines, 2012

E. De Moor, D. K. Matlock, J. G. Speer, M. J. Merwin, Scripta Mater., 2011, 64 (2),

185

.

Ferrite

Austenite

Image courtesy of Hyokyung Sung

and Sharvan Kumar, School of

Engineering, Brown University

Hydrogen

Atmosphere,

Furnace

Cool

Experimental Laboratory Heats

Following previous literature • P. Gibbs, Ph. D. Thesis, Colorado School of Mines, 2012

Fe-0.15 C-10 Mn-1.5 Al-0.2 Si (wt pct)

Expected Result from Previous Literature

[1] P. Gibbs, Ph. D. Thesis, Colorado School of Mines, 2012

Yield

Strength

(MPa)

Tensile

Strength

(MPa)

Total

Elongation

(%)

Uniform

Elongation

(%)

Expected1 780 1090 46 45

Furnace cooling after reversion annealing produced

exceptional tensile properties, however, lower strengths

than targeted.

Tensile Properties After Reversion Annealing

Yield

Strength

(MPa)

Tensile

Strength

(MPa)

Total

Elongation

(%)

Uniform

Elongation

(%)

Expected1 780 1090 46 45

Furnace

Cooled 810 915 45 39

Hydrogen

Atmosphere,

Furnace

Cool

Experimental Laboratory Heats

Following previous literature • P. Gibbs, Ph. D. Thesis, Colorado School of Mines, 2012

Fe-0.15 C-10 Mn-1.5 Al-0.2 Si (wt pct)

Nitrogen

Atmosphere,

Air Cool

Tensile Properties After Reversion Annealing

Exceptional properties near DOE (1200 MPa) target

can be achieved using 10Mn concept.

Yield

Strength

(MPa)

Tensile

Strength

(MPa)

Total

Elongation

(%)

Uniform

Elongation

(%)

Expected 780 1090 46 45

Furnace

Cooled 810 915 45 39

Air Cooled

(ground) 750 1165 37 34

QUENCHED AND PARTITIONED

(Q&P) STEEL

Laboratory Results from Experimental Heats of

Q&P Microstructural Evolution

Time

Tem

pe

ratu

re

0 RT

Martensite

Start

Ms

Austenite

J. Speer, D. K. Matlock, B. C. De Cooman, and J. G.

Schroth, Acta Materialia, vol. 51, pp. 2611-2622, 2003.

Austenite

+ Martensite Carbon Enriched Austenite

+Carbon Depleted Martensite

+ “Fresh” Martensite

(+Ferrite)

Carbon Enriched Austenite

+Carbon Depleted Martensite

Martensite

Finish

Q&P Microstructures

1 m

Ferrite

Martensite

Austenite SEM

500 nmEBSD

Austenite

G. Thomas, J. Speer, D. Matlock, J. Michael," Microscopy and Microanalysis, vol. 17, pp. 368-373, 2011.

Q&P Steels—Tensile Properties

Previous Q&P literature has shown the capability to produce a wide range of

mechanical properties with enhanced elongation.

E. De Moor, P.J. Gibbs, J.G. Speer, D.K. Matlock, and J.G. Schroth, AIST Trans., Iron & Steel Technology, Vol. 7, No. 11, 2010, pp. 133-144.

E. De Moor, J.G. Speer, D.K. Matlock, J.-H. Kwak and S.-B Lee, ISIJ International, 51(1), 2011, pp. 137-144.

Experimental Laboratory Heats

Following previous literature • E. De Moor, J.G. Speer, D.K. Matlock, J.-H. Kwak and S.-B Lee, ISIJ

International, 51(1), 2011, 137-144.

Fe-0.30 C-3 Mn-1.6 Si (wt pct)

Time

Tem

pe

ratu

re

0 RT

Ms

Mf

Ms

820 °C

180 °C

400 °C, 100 s

[1] E. De Moor, J.G. Speer, D.K. Matlock, J.-H. Kwak and S.-B Lee, ISIJ International, 51(1), 2011, 137-144.

Expected Result from Previous Literature

Yield

Strength

(MPa)

Tensile

Strength

(MPa)

Total

Elongation

(%)

Uniform

Elongation

(%)

Expected1 1055 1490 17 15

Tensile Properties after Q&P Treatment

Excellent properties near DOE (1500 MPa) target

can be achieved using Q&P concept.

Yield

Strength

(MPa)

Tensile

Strength

(MPa)

Total

Elongation

(%)

Uniform

Elongation

(%)

Expected 1055 1490 17 15

Achieved 1220 1540 19 16

Advanced Methods–Coupled DIC and Synchrotron Diffraction

QP980

10Mn

Work performed by Prof. Fadi Abu-Farha, Clemson University; Louis

Hector Jr., General Motors;Argonne National Lab

Digital Image Correlation (DIC) System

Sample

Detector

Tensile Frame

CONCLUSIONS

Next Steps and

Conclusions

Laboratory materials with tensile properties near DOE targets have been produced

Additional (larger) lab heats are underway

Materials are being distributed to project partners for multi-scale testing and model calibration

Acknowledgments

ICME “Steel Experts” Team:

• AK Steel—Kavesary Raghavan, Luis Garza

• ArcelorMittal—Debanshu Bhattacharya

• General Motors—Lou Hector Jr.

• Colorado School of Mines—Professors David Matlock, Emmanuel De Moor, & John Speer, Rana Radhakanta

• Nucor Steel—Dean Kanelos

• U.S. Steel—Bart DePompolo

• Steel Market Development Institute—Jody Hall, Eric McCarty

Brown University—Hyokyung Sung and Sharvan Kumar

Clemson University—Prof. Fadi Abu-Farha

Argonne National Lab

DOE Acknowledgment/Disclaimer

This material is based upon work supported by the Department of Energy National Energy Technology Laboratory under Award Number: No. DE-EE0005976.

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Such support does not constitute an endorsement by the Department of Energy of the work or the views expressed herein.

Thank you for your attention.

Grant Thomas

grant.thomas@aksteel.com