Metal Forming Simulations
Their Use in Aluminum FormingApplications
M. Sc. Canderim Önder; Alutec Metallwaren GmbH & Co. KG
11. Simufact Roundtable; 13th October 2009
Outline
• Company profile
• Determination phases of the metal forming simulation software selection
• Case studies
Company Profile
• alutec supplies creative solutions by the aluminum impact extrusion method.
• alutec is an expert on cold forming of aluminum
• Machining centers realize metal cutting operations
• Founded in 1988, and located in Sternenfels
• ~200 employees
• 26 million € turnover
• Annual processed tonnage : 1250 ton.
Main Product Groups
Housings
• Engine management
• Airbag control
• Ultrasonic sensors
• Path measurement
• Shock absorber
Heat Sinks
• Air conditioning electronicsin motor cars
• LED electronics in motor cars
• PC electronics
Mechanical Components
• Pistons / push rods for gearbox control
• Pistons for wheel brakes in motor cars
• Pistons for hand brakes in commercial vehicles
… and assemblies
World Wide Custumers
USA
Mexico
France
Spain
Germany
UK
The NetherlandsDenmark
Czech Republic
Poland
Austria
KoreaJapan
Determination Phases of a Metal FormingSimulation Software
• Intention of the board
• Assignment of a responsible engineer
• Presenting the abilities of the available software on the market
• Determination of the technical needs
Determination Phases of a Metal Forming Simulation Software• Software Comparison (Self-evaluation / proof of known defects)
Material: AW-6082 AlMgSi1
Press Type: Crank Press
Forming Errors
•Sucking defects at the base
•Uncontrolled diameter of the center hole
Aim
• Visualization of the defects in 3 FE softwares
• To reveal the flowlines of the part and compare by FE results
Determination Phases of a Metal Forming Simulation SoftwareNone of the softwares could visualize sucking defect
Contact Pressure Distribution:
SimufactFlowline Visualisation:
Determination Phases of a Metal FormingSimulation Software
Flowline Comparison
Simufact
More realistic
Determination Phases of a Metal Forming Simulation Software
Underfilling or flow through defect
Lap formation
OR flw. through
Flow through defect!! Only in one corner.
Determination Phases of a Metal Forming Simulation SoftwareBuckling Ratio
(Critical h/d ratio has been determined by experiments. At the critical ratios FE simulations must have shown the initiation of the buckling)
Simufact√ √
Case Studies
Die Failure Prevention (1)
• The part is produced by forward can extrusion. Tool life was only a few.
Die Failure Prevention (2)
• Principal max. Stress distribution during forming
Die Failure Prevention (3)
• Analyses showed that the corner of the die needs to have a positive pre-stress.
• On the figure at the right, the new idea to prolong the die life is sketched; the parameters h and ∆z are to be optimized
• The tooling is mounted to the rest of the die part with a bolt. The prestressing effect of the bolt has been also taken into account
• Optimized configuration at max. punch load. Tooling is still in use
Principal max. stress dist.
1900
Cave on the Product Wall (1)
• During cold forming, bottom and the side walls of the product were deflected
• The whole process has been modeled, including ejection process
forming ejection
• The FE results were identical with the actual product.
Cave on the Product Wall (2)
• The previous product is milled to obtain an aluminum frame.
• To detect if the movement of the chuck causes permanent plastic deformation on the frame, an analysis has been performed on (cold forged + trimmed) part.
Symmetry surface
Symmetry surface
Chuck movement
• A small amount of plastic shape change has been detected because of the chuck movement.
Conclusion
• Especially with its accuracy, Simufact has been selected as metal forming simulation tool by alutec.
• Sucking type failures could be correctly visualized by flowlines
• In 3D applications, FV solution serves a quick evaluation method. But the ultimate results must be verified with FE, unless the process has extreme complexity.
• In some cases, the exact reason of a problem might be understood only if the whole cold forming process history is modeled.
• GP_GUI must be preserved in simufact product group. Its advanced applications and postprocessing capabilities are unique.