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Forming & Fabricating Community of SMEhttp://sme.org/ffc/
The Forming & Fabricating Community focuses on key metal forming and fabricating technologies. The community also engages members as technical experts and manufacturing practitioners. They support the sharing of manufacturing knowledge and solutions through professional networking.
Community Advisors: Brian Peshek, Dean Philips, Jon Brouwer,
Charles Caristan (your host today), Bob Iossi, Eric Kam, Viwek Vaidyahttp://sme.org/ff-advisors/
Housekeeping Rules
� 1.5 hour webinar + 30 min. Q&A
� All participants will be muted during the webinar
� During the presentation, you can log along your questions in the Q&A window of the WebEx screen.
� Q&A session immediately following the presentation: all participants will be unmuted
� The whole presentation is recorded and a web link to the recording will be emailed by SME to all attendees.
Meet the Presenters:
Professor Susil K Putatunda
Department of Chemical Engineering and Materials Science and
Engineering,
Rozalia Papp
Business Development Specialist / Heat Treatment
www.us.airliquide.com
Frederick J. (Rick) Diekman
President and Founder www.metal-wear.com
Controlled Thermal Processing, Inc.
Deep Cryogenic Treating (DCT) of Metals,
an Emerging Technology
Rozalia Papp
Sr. Business Development Specialist (Heat Treat & SPAL)
Frederick J. Diekman
President
Susil K. Putatunda
Professor, Department of Chemical Engineering and Materials Science
and Engineering,
Controlled
Thermal Processing, Inc.
Presentation Objectives
• Define Deep Cryogenic Treating (DCT)
• Metallurgical timeline and development
• Discuss the Process
• Show Some of the Research
• Show Some of the Possible Economic Impacts of the Process
• The future of DCT science
Deep Cryogenic Treating (DCT) is:
The Creation of Structural and Mechanical Changes in Materials By Exposing Them to Cryogenic
Temperatures.
The Cryogenic Society of America
Considers Cryogenic Temperatures to be
Temperatures Below 1200K
(-2440F, -1530C)
(00K= Absolute Zero)
Why is it not more well known?
• Man has been changing materials with heat for many thousand years.
• Man has been using heat to treat metals for 7500 years.
• Man has had cryogenic temperatures for only ~100
years.
Phase Diagrams Rarely Show Phases Below Zero Degrees Celsius
0ºC
http://wikis.lib.ncsu.edu/images/9/95/CH434_binardsc.gif
-273ºC?
Fig 1: Microstructures of samples Fig 1: Microstructures of samples austemperedaustempered at 550at 550°°FF
--BainiticBainitic ferrite and austenite with graphite nodules.ferrite and austenite with graphite nodules.
--very fine scale ferrite and austenitevery fine scale ferrite and austenite
Fig.2: Microstructure of the cryogenically treated Fig.2: Microstructure of the cryogenically treated sample showing the presence of carbide.sample showing the presence of carbide.
The Effect Of Cryogenic Processing On The Mechanical Properties Of
Austempered Ductile Cast Iron (ADI)
The Effect Of Cryogenic Processing On The Mechanical Properties Of
Austempered Ductile Cast Iron (ADI)
Air Separation Plants
The gases from the air, nitrogen (N2), oxygen (O2) and argon (Ar) are produced from the fractional distillation of air.
- 320ºF
- 297ºF
- 302ºF
Wkipedia Says
• A cryogenic treatment is the process of treating workpieces to cryogenic temperatures (i.e. below −190 °C (−310 °F)) to remove residual stresses and improve wear resistance on steels.
• The process has a wide range of applications from industrial tooling to improvement of musical signal transmission. Some of the benefits of cryogenic treatment include longer part life, less failure due to cracking, improved thermal properties, better electrical properties including less electrical resistance, reduced coefficient of friction, less creep and walk, improved flatness, and easier machining.
Kinetics of Cryogenic Treatment(ASM Handbook Volume 4 Heat Treating, ©1991 and last revised in 2001)
“There are several theories concerning reasons for the effects of cryogenic treatment. One theory involves the more nearly complete transformation of retained austenite into martensite. This theory has been verified by x-ray diffraction measurements. Another theory is based on the strengthening of the material brought about by the precipitation of submicroscopic carbides as a result of the cryogenic treatment. Allied with this is the reduction in internal stresses in the martensite that happens when the submicroscopic carbide precipitation occurs. A reduiction in microcracking tendencies resulting from reduced internal stresses is also suggested as a reason for improved properties.The absence of a clear-cut understanding of the mechanism(s) by which cryogenic treatment improves performance has hampered its widespread acceptance by
metallurgists. Nonetheless, it is important to review the studies done to determine the effects of cryogenic treatment on the performance of steel in a variety of applications.”
What Cryogenic Metallurgy Does
• Relieves Residual Stresses (All Metals)
• Refines the Crystal Structure (All Metals) (Unproven Theory)
• Modifies Point Defects in the Crystal Structure (All Metals)
• Precipitates Fine Eta Carbides (Steels With Carbide Forming Elements Only)
• Converts Retained Austenite to Martensite (Hardened Steels Only)
Basic Metallurgy Teaches
For all temperatures above 0oK, there is a thermodynamically stable concentration of vacancies and interstitial atoms. Introducing a point defect into a crystal increases its internal energy vis-a-vis a perfect crystal. (Italics added).
Russell, Alan M., and Lee, KOK Loong, STRUCTURE-PROPERTY RELATIONS IN NONFERROUS METALS John Wiley and Sons 2005 Page 18
Results of Deep Cryogenic Treating
• Increased abrasion and wear resistance
• Increased fatigue life
• Increased ductility
• Reduced residual stresses
• Mild increase in tensile strength
• A change in vibration characteristics
Typical Cycle Steps in Cryogenic Metallurgy
Hold or Soak
Room Temp
Ram
p D
ow
n
Ram
p U
pTem
per R
amp
Up Temper Hold
Tem
per R
am
p D
ow
n
Time
Temperature
MEI machine uses spraybartechnology
Insulation is a mineral wool.
300 Below uses electric refrigeration compressors to -100ºF, then spraybars
Insulation is polyurethane foam
Cryo - Processors
Vacuum Insulated Machines by Applied Cryogenics Heat Exchanger TechnologyCapable of -320ºF to +320ºF
LN2 Consumption at -300ºF 7 liters/hour
Cryo - Processors
InsulationPrice versus Performance
• R5 or R1500, its your (extreme) choice• Overall Efficiency, four basic factors:
1. Thermal conductivity2. Vacuum level ($$$)3. Cost of labor ($$) and materials ($)
Source:http://lartpc-docdb.fnal.gov/0002/000217/001/Cryogenic_Insulation_Technology.pdfCryogenic Thermal Insulation Systems, James E. Fesmire, Stan D. Augustynowicz
MATERIAL High Vacuum
Medium Vacuum No Vacuum
High Vacuum .5 to 5
Nitrogen gas at 200 18.7
Fiberglass, 16 kg/m 2 14 22
PU foam, 32 kg/m 21
Cellular glass foam, 128 kg/m 33
Perlite powder, 128 kg/m 1 16 32
Aerogel beads, 80 kg/m 1.1 5.4 11
Aerogel composite blanket, 125 kg/m 0.6 3.4 12
MLI, foil and paper, 60 layers, 79 kg/m 0.09 10 24
! LCI, 30 layers, 78 kg/m3 0.09 1.6 14
Representative k Values (mW/mK)
Source: http://lartpc-docdb.fnal.gov/0002/000217/001/Cryogenic_Insulation_Technology.pdf
Cooling Cost Factors in Deep Cryogenic Processing
The Major Cost is the Liquid Nitrogen
1. Cooling the Load .25L/pound of steel2. Cooling the inside of the machine .25L/pound of steel3. Heat infiltrating through the insulation insulation and construction
dependent4. Heat created by air circulation 1.5 L/hour/horsepower
Performance Experiments
Effects of Cryogenically Treated Steel
Comparison of wear-resistance ratios for five high-carbon steels soaked at -84°C and -190°C
(-120 and -310°F). Soaking temperatures below -84°C does not significantly change the
hardness of the material.
Theories about the reasons for the effects of cryogenic treatment include a more nearly complete transformation of retained austenite into martensite; precipitation of submicroscopic carbides; and a reduction in internal stresses in martensite that occurs when the submicroscopic carbide precipitation occurs. A reduction in microcracking tendencies resulting from reduced internal stresses is suggested as a reason for improved properties.
(Source: ASM Handbook, Vol. 4, Heat Treating, ASM International, 1991, p 205
Heat Treating Progress: Volume 2, Number 49, December 14, 2007)
Army Aviation & Missile Command Research With Illinois Institute of Technology Research
Institute
• Study of wear resistance under Hertzian contact stresses of 9310 steel.
• 50% extra pitting resistance
• 5% more load carrying capacity
• 400F to 600F higher tempering temperature
Wind Turbine Gear Boxes
• Failure is biggest maintenance cost.
• 5 year predicted life
• Many fail earlier
• Replacement cost of $500,000
• Current installation rate is approximately 2900 turbines /year.
University of Trento, Trento, Italy/GKN Corp.Effect of Deep Cryogenic Treatment of the Mechanical Properties of
Tool Steels(A. Molinari, M. Pellizzari, S. Gialanella, et al. 2001 Journal of Materials Processing
Technology.)
• Studied M2 & H13.
• Improved hardness homogeneity.
• Led to 50% cost reduction.
• Increased toughness on H13.
• No significant changes to microstructure except reduction in retained austenite.
• Need to study the sub-microstructure for mechanism.
Cryogenic Treatment of M1, EN19 and H13 Tool Steels to
Improve Wear Resistance(IE(I) Journal-MM, Vol 86, October 2005 pages 64, 65, 66; P Sekhar Babu,
Member, P Rajendran, Non-member, Dr K N Rao, Fellow)
Cryogenic treatment is said to improve wear resistance of tool and die steels and implemented at many places for that purpose. Although it has been confirmed that cryogenic treatment improves wear resistance and tool life, the process has not been standardized with inconsistent results varying from researcher to researcher.
In this work the authors have studied the improvement in wear resistance of M1, EN19 and H13 tool steels after cryogenic treatment. The materials were tested for improvement in abrasive wear resistance after cryogenic treatment at different temperatures below 0°C.
All the samples were first heat treated as per standard norms and re tempered after cryogenic treatment. The samples were treated at 0°C, -20°C, - 40°C, -80°C and -190°C.
It was observed that the wear resistance improved for all the samples from 315% to 382% depending on the material.
Tool Steel Tooling Accounts for up to 20% of the cost of production of things we buy.
Annual Market for tool steels is 32,000,000 Kg
• Drills• Milling Cutters• Die Casting Dies• Stamping Dies• Knives• Forging Dies
• Molds• Extruding Dies• Forming Rolls• Broaches
Brakes• Lab Tests indicate up to 7 times life.
• Specified by the US Postal Service after extensive testing.
• California County Sheriff fleet of 450 Ford Crown Victoria’s saving over $650,000/year based on a one year practical test.
• United States Commercial & Government Fleet --31,600,000 Vehicles
• Proven environmental benefits
Copper Welding Electrodes Last Longer
(Sub-zero Treatment of Steels Technology/Processes/Equipment, Linde AG | Linde
Divison/82049 Hollriegelskreuth/Germany).
Cryogenic treatment of copper welding resistance electrodes increases their life by a factor 2 to 9.
These electrodes are used by the hundreds of thousands in automotive and appliance industries.
Cryogenic Treatment of Cutting Tools
(Andrew Yong A thesis submitted in 2006 for the degree of Doctor of Philosophy,
Department of Mechanical Engineering’ National University of Singapore)
•Cryogenic treatment significantly alters the microstructure of tungsten carbide.
•Cryogenic treatment increases the hardness of the tungsten carbide tools.
•Cryogenically treated tungsten carbide tools in continuous cutting operations show a marked decrease in tool wear during the initial duration of cutting as compared to untreated tools.
•Cryogenically treated tungsten carbide tools perform well in intermittent cutting operations, such as milling operations.
Other Areas of Use
• Electronics
• Stereo Equipment
• Chip Manufacturing
• Plastics
• Stabilization of Metals
• Springs
• Sports Equipment
The Cryogenic Society of America
CSA is a non-profit technical society serving all those interested in any phase of cryogenics, the art and
science of achieving extremely low temperatures —
almost absolute zero.www.cryogenicsociety.org
Cryogenic Research Database
• Joint effort between ASM & CSA
• Papers & Articles reviewed by a committee of experts
• Complete papers published where possible
• Available to the public
www.cryogenictreatmentdatabase.org
ASM Cryogenic Processing Sub Committee
• Educate Markets
• Encourage and Coordinate Research
• Discourage Frivolous Claims
• Create a Research Database
• Review Cryogenic Processing in ASM Publications
• Provide Peer Review of Research
To Conclude
• DCT can further change structure and properties of metals.
• DCT can improve mechanical properties and reduce production costs.
• Research & practical testing have proven the process in many cases.
• Next steps in the DCT science shall include but not be limited to:
– Understand phase changes down to 0ºK (absolute Zero)
– Determine the best processing parameters for each material )metallic and non-metallic)
– Develop a specification driven, industry approved process for each material and each application
– Include the new scientific advancement in the teaching system