Qualifica Dei Processi Produttivi Controllati Con Metodi Statistici

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MSC.SOFTWARE WORLDWIDE AEROSPACE CONFERENCE and
TECHNOLOGY SHOWCASE TOULOUSE, April 8-10, 2002
Numerical simulation of the Super Plastic
Forming Process of the EFA 2000 Under Carriage
Door F. Giordano? A. Natale ? M. Calcagni?

?Alenia Aerospazio Divisione Aeronautica ?
MSC. Software S.r.l. Italy
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR

OBJECTIVES AND GOALS
In the last years, more and more frequent
utilization of the S.P.F.
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR

OBJECTIVES AND GOALS (CONTD)

• Tool chosen for the numerical simulation MSC.Marc

• Marc code applied to a concrete problem of the
  Alenia Aerospazio - Divisione Aeronautica
• S.P.F. of the Under Carriage Door of the EF2000

• Steps followed

• numerical simulation of the S.P.F. process for
  the U/C Door

• comparison between numerical and experimental
  readings of the door thickness

• study of the simulation of the friction between
  die and forming plate

• optimization of the loading curve

• analysis and application of the new capabilities
  Marc

• auto-adaptive remeshing

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR

SUPERPLASTICITY

• S.P.F. process able to produce very complex
  structures, based on the superplasticity of
  various kind of material

• Superplasticity particular state achieved by
  metals, alloys, ceramic materials in specific
  temperature and pressure conditions

• In this state, possibility of undergoing very
  high deformation without necking

• Condition to be verified to have superplastic
  state

• grains little dimensions (1?10 mm)
• forming temperature higher than 50 fusion
  temperature
• low deformation velocity
• strain rate sensitivity factor at least equal to
  0.3

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR

S.P.F. SIMULATION FOR EF200 U/C DOOR

• In the real process

• heated ( T 485 10C) dies and presses are used
• initial plate thickness 2.5 mm
• target strain rate410-4 sec-1
  

• In the numerical simulation

• transfer of the die geometric model from CATIA by
  Direct Access CATIA
• realization of the F.E.M. model of the plate to
  be formed
• reproduction of the F.E.M. model of the die
• application of the real loading curve and of the
  real constraints

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
U/C DOOR EF2000
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR

F.E. MODELS OF THE PLATE AND OF THE DIE
DIE GRIDS 77576 SURFACES
19394
PLATE NODES 14641 ELEMENTS
14400
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
MATERIAL CHARACTERIZING

• Material isotropic and with a rigid-plastic law

• Utilization of a law (Power law)

with A0

• Bibliographic research to find the values of B
  ed n

by curve at 505 C B509.69 Nsec/mm2
n0.65
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
LOADING AND CONSTRAINTS OF THE U/C DOOR MODEL

• Real loading hot pressurized air insufflated on
  the upper and on the lower part of the plate

• Numerical loading the real differential pressure
  has been applied to the plate

• Constraints edges of the plate clamped

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
RESULTS OF MSC.Marc ANALYSIS HISTORY OF THE
THICKNESS DISTRIBUTION
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
RESULTS OF MSC.Marc ANALYSIS HISTORY OF THE
THICKNESS DISTRIBUTION (CONTD)
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
RESULTS OF MSC.Marc ANALYSIS HISTORY OF THE
THICKNESS DISTRIBUTION (CONTD)
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
LOCATION OF THE EXPERIMENTAL AND NUMERICAL
READINGS

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
EXPERIMENTAL-NUMERICAL READINGS CORRELATION
PART A
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
EXPERIMENTAL-NUMERICAL READINGS CORRELATION
PART B
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
STUDY OF DIE - PLATE FRICTION

• Non perfect agreement in few points of readings

study of new MSC.Marc capabilities

• Attention on a quick tool the test of the door

• Realization of a new detailed F.E.M. for the die
  and for the initial plate related to the test

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
STUDY OF DIE -PLATE FRICTION (CONTD)

• More reliable model of the friction (Coulomb
  friction)

FfrmFn

• Model of the friction available from Marc

FfrmFn2/p arctan (Vr/RVCNST)t

• Choice of RVCNST so that the Coulomb friction has
  been used

m 0 m 0.1 m 0.25 m 0.5
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
TEST OF THE DOOR FRICTION PARAMETRIC STUDY
Numerical-Experimental thickness correlation
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
STUDY OF OPTIMIZED LOADING CURVE

• Operative application to improve the S.P.F.
  process study of an optimized loading curve

• By utilizing the new Marc capability, the loading
  curve is the main result

• Necessity of indicating the direction, the versus
  of the loading and the maximum value of the
  pressure to be applied (p 1N/mm2)

• Choice of the ending termination

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
U/C DOOR EF2000 STUDY OF THE OPTIMIZED LOADING
CURVE WITH AUTO-ADAPTIVE REMESHING

• Study of the new MSC.Marc capability to have a
  finer mesh in the critical zones

• First level of remeshing

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
U/C DOOR EF2000 STUDY OF THE OPTIMIZED LOADING
CURVE WITH AUTO-ADAPTIVE REMESHING
Thickness and strain rate distribution
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
U/C DOOR EF2000 STUDY OF THE OPTIMIZED LOADING
CURVE WITH AUTO-ADAPTIVE REMESHING
Thickness and strain rate distribution
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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
SUMMARY OF THE TIME CALCULATION

• Processor used IBM RS/6000 449 Model 170 W/S -
  1Gb of Ram 18 Gb of Internal Disk Drive

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NUMERICAL SIMULATION OF THE S.P.F. PROCESS OF THE
EFA - 2000 UNDER CARRIAGE DOOR
CONCLUSIONS

• A study on the possibility of numerically
  simulating the S.P.F. has been performed

• Numerical-experimental comparison demonstrates
  the opportunity of the Code MSC.Marc utilization
  like a good tool of numerical simulation

• A study of simulation of die-plate friction has
  been performed

• The capability of producing an optimized loading
  curve has been studied and applied

• The capability of realizing an auto-adaptive
  remeshing has been explored

• Advantages of a numerical simulation

• a more detailed knowledge of all the parameters
  of the process
• possibility of knowing the optimized loading
  curve
• numerical evaluation of the influence of the
  parameters on the process
• reduction of the experimental tests
• possibility of knowing the optimized thickness
  distribution of the initial plate