PREFORMS - PReform Engineering using Forward and Reverse Modeling Simulation
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Deformation Control Technology, Inc. and Wright State University PREFORMS - PReform Engineering using PREFORMS - PReform Engineering using Forward and Reverse Modeling Simulation Forward and Reverse Modeling Simulation
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PREFORMS - PReform Engineering using Forward and Reverse Modeling Simulation. Deformation Control Technology, Inc. and Wright State University. Features. A reverse forming simulation software tool. A true design tool not just a simulation tool. - PowerPoint PPT Presentation
Transcript of PREFORMS - PReform Engineering using Forward and Reverse Modeling Simulation
Deformation Control Technology, Inc.and
Wright State University
PREFORMS - PReform Engineering using PREFORMS - PReform Engineering using Forward and Reverse Modeling SimulationForward and Reverse Modeling Simulation
FeaturesFeatures
A reverse forming simulation software tool. A true design tool not just a simulation tool. Incorporates reverse simulation and optimization. UNIX and PC platforms. Works with DEFORM from Scientific Forming
Tech. Corp. Continued development and support by WSU and
DCT. Customer support availability .
FeaturesFeatures
Capable of both forward and backward material deformation simulations.
Simulates plane strain and axisymmetric forging shapes
Friendly graphical user interface.
Capable of producing detailed deformation information under combined mechanical and thermal loading.
Solves a large variety of problems by suitably altering the model process parameters.
Ability to quantitatively predict metal flow using FEM
PREFORMS Benefits
Design preform die shapes to achieve complete die fill.
Reduce material waste, i.e. achieve a net shape forging process by optimizing material utilization and minimize flash.
Eliminate surface defects, i.e. laps and voids.
Eliminate internal defects, i.e. shear cracks and poor microstructure.
Minimize effective strain and strain-rate variance in workpiece.
Design optimal process parameters such as forming rate (die velocity) as well as initial workpiece and die temperatures.
PREFORMSPREFORMS
General Flowchart showing overview of PREFORMS program
Design GoalsDesign Goals
Die Shape Optimization: Number of preform stages Preform shapes
Optimal Forging Process Parameters: Press velocity profile Die and billet temperatures
Optimal Process Constraints: More uniform strain, strain-rate and temperature
distributions Eliminate localized deformations Eliminate forging defects and cavities
MethodologiesMethodologies
Two distinct design strategies for preform design:
Backward Tracing Method
Numerical Optimization Method
Backward Tracing MethodBackward Tracing Method
Starts with final shape (die filled).
Simulation is conducted in reverse.
Preform shape evolves as material is released from dies.
Path is not unique.• Requires boundary node detachment criterion
Resulting shape depends on the detachment criteria used.
Backward Tracing MethodBackward Tracing Method
Divide die surfaces into a number of straight line or arc segments.
Record the time at which each die segment comes into contact with the workpiece during the forward simulation with a trial preform shape.
Modify the recorded time sequence if the trial preform does
not satisfy the design objectives.• Die fill requirements• Flash size requirements• Material flow characteristics
The modified contact time sequence is then used as the boundary node detachment criterion for the backward deformation simulation.
Modification GuidelinesModification Guidelines
Multi-Cavity Forging: Contact time of earliest filled cavity is reduced to allow all
cavities to be filled at the same time.
Underfilled Cavity: Contact time of underfilled die segment is defined as time
of final stroke. Contact times of adjacent die segments are reduced to the closest die segment where time is defined.
Modification GuidelinesModification Guidelines
Cavity-Fill Before Final Stroke: Contact times of all die segments reduced by same value.
Value is the difference between the final stroke and the time at fill.
Large Flash: Contact time for outermost die segments (flash) is the
time at which upper die is at required final position.
Turbine Disk Forging ProcessTurbine Disk Forging Process
Turbine Disk Preform DesignTurbine Disk Preform Design
Material flow patterns during backward simulation of final forging stage.
Preform shape (most of the die contact nodes are detached)
Turbine Disk Preform DesignTurbine Disk Preform Design
Forward verification of blocking stage using blocker designed by backward simulation.
Blocker filled
Turbine Disk Preform DesignTurbine Disk Preform Design
Forward verification simulation of generic turbine disk.
Numerical Optimization MethodNumerical Optimization Method
Nonlinear sensitivity analysis of plastic deformation.
End goals are achieved with defined flow requirements.
Preform shape is optimized using B-splines.
Iteratively optimized using forward simulations.
Method is very general and applicable to other unit processes.
Optimization VariablesOptimization Variables
Spline Control Points as Optimization Variables
Iterative HistoryIterative History
Evolution of Preform Shape During the Design Search
Iteration
23
4
56
1
Optimum
Optimal Forging Sequence - 1Optimal Forging Sequence - 1
Starting Billet for Stage I Operation
Final Forging for Stage I Operation
Optimal Forging Sequence - 2Optimal Forging Sequence - 2
Stage I Forging Transferred to Stage II Dies
Stage II Final Forging using Stage I Preform (Eff. Strain Variance =
1.26)
Personnel
Dr. Ramana GrandhiProfessor Wright State University
Dr. Zhichao (Charlie) LiDr. B. Lynn FergusonMr. Greg Petrus Mr. Andrew FreborgDeformation Control Technology, Inc.
Future DirectionsFuture Directions
Increase robustness of sensitivity analysis Continue excellent work started and continuing at Wright
State and now Deformation Control Technology
3 Dimensional Capability Dr. Grandhi has been investigating 3D
Added dimension of DCT DCT is now combining their industrial skills and successes
with the academic excellence of WSU to make PREFORMS a reality.
Contact InformationContact Information
Visit the web at www.DeformationControl.com.
Deformation Control Technology, Inc.7261 Engle Road, Suite 105
Cleveland, OH 44130
Phone: 440-234-8477 Fax: 440-234-9140
A Revolutionary Heat Treatment Simulation Software Tool
Copyright DCT Inc. 2002
A commercial finite element based software tool for heat treating
State-of-the-art mechanical and transformation kinetics models
Accurate description of heat transfer during heating and cooling steps
Validated carburization modelAddresses immersion quenching,
intensive quenching methods, gas quenching and press quenching
DANTE/KIVATM Capabilities DANTE/KIVATM Capabilities
Design Tool Results•Carburization•Microstructural Phases•Residual Stress•Dimensional Change
DANTE/KIVA Additional Benefits:- User’s Group Participation- Material / Process Database- Development Participation- Local Technical Support/Customer Service
• DCT - Cleveland, Ohio
• NRS Associates - Hartford, CT
• MLC Technical Consulting - Livermore, CA
• Sierra Vista Technology - Albuquerque, NM
TYPICIAL PARTS MODELED IN DANTE/KIVA SYSTEM
Complex Gear Shapes
Shafts
Coil Springs
DANTE™ - Approach to AnalysisDANTE™ - Approach to Analysis
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PD
Microstructure Dimensional ChangesResidual Stresses
Meshing TemplatesMechanics Model & Databases
Kinetics Models & DatabasesHeat Transfer Methodology
Carburization
