Efficient Setup and Documentation

Transcription

1 Efficient Setup and Documentation Foto: ISF of Simulations for Welding and Heat Treatment with DynaWeld Simulationsforum Weimar till Tobias Loose Ingenieurbüro Tobias Loose, Herdweg 13, D Wössingen, 1

2 Heat treatment overview Type of heat treatment Quenching Case Hardening Inductive hardening Press hardening Single process steps Heating Thermal Heating Inductive Heating Carburisation Quenching Tempering Design of properties by local change of material properties and microstructure 3

3 Welding overview welding structure analysis Type of Welding Weld Process Type - Arc Welding - GMAW, SAW, TIG - Laser - Electron Beam - GMAW-Laser-Hybrid - Resistive Welding, RSW Single process steps Clamping Predeformations Heating Cooling single or multi layered welds, tack welds Reheating Dimension Grinding and Rewelding 10 µm mm Tempering Distortion - Residual Stress - Material Properties after Welding 4

4 Substructuring of models for welding and heat treatment Geometry Meshing or import mesh from prior steps Trajectories Heat Source Clamps and Boundarys Heating Carburization Quenching Media Material Data, and parameter calibration Process FEM additional settings: load, contact, cinematics... S I M U L A T I O N M O D E L 5

5 Benefit of sub structuring Material specialist Mesh Complex simulation task with many disciplines specialist easy to mange by task sharing FEM specialist Welding specialist outsourcing single tasks Heat Treatment specialist 6

6 Definition of simulation steps R E A L I T Y Mesher PreProcesssor DynaWeld S I M U L A T I O N M O D E L P O S T Solver LS-DYNA F I L E O U T P U T PostProcesssor R E S U L T LS-Pre-Post DynaWeld repesents a simulation environment with special preprocessors 7

7 DynaWeld environment and preprocessor 8

8 DynaWeld environment and preprocessor DynaWeld is not an Island-Solution! Customer defined Environment: Mesher PreProcessor PostProcessor Auxilary Software Linux and Windows Excel and Libre Calc Plug In for existing Software environment as well as stand alone Process Chain Interface Material Simulation Welding Process Simulation Heat Treatment and Welding related auxilary Tools User defined Keyword no limitation in modeling Supports LS-DYNA FE-Code one Code - many Solvers - one License Fee 9

9 Material Foto: Edyta Łopatecka 10

10 Phase transformation during cooling CCT-diagram Quelle: Bernd Hochholdinger, DYNAmore Swiss 11

11 Phase kinetic models Law: Koinstinen-Marburger Tstart: a: Parameter: Start Temperature kinetic faktor Use: MS KM f(temperature) diffusionless transformation Austenit Martensit 12

12 Phase kinetic models Law: based on Avrami equitation extended by Leblond generalized JMAK Jonhson-Mehl-Avrami-Kolmogorov xeq: n: t: f,f': Parameter: Proprotion at equilibrium (T) form parameter (T) kinetic faktor (T) Leblond factor (dt/dt) Use: f(temperature, temperture gradient, time) diffusion-driven transformation Austinitisation, Tempering Austenite Ferite, Perlite, Bainite phase transformation Aluminium PEQ N TAU F, F', Advantage: no limitation on material type nor chemical composition. Fitting according: temperatur(t) and temperature rate(dt/dt) Disadvantage: needs calibration on existing CCT or TT 13

13 Materials with phase kinetic models in LS-DYNA *MAT_254 / *MAT_GENERALIZED_PHASE_CHANGE Heat treatment Welding Laws: Koinstinen Marburger Oddy Kirkaldy generalized JMAK Time criterium list might be extended userdefined assignment of laws all materials Features: 24 Phases Shells, Solids, 2D-shells Welding features Phase transformation strain Transformation induced plasticity (TRIP) Subcycling for phase transformation Tempering Hardeness computation Simulation of PROCESS-CHAIN feasible 14

14 Selected features: DTEMP Phase transformation calculation temperature requires limit on tempearature step Phase transformation shall not reduce time step of mechanical solver DTEMP = maximum allowed temperature step drives subcycle for phase transformation: 15

15 *MAT_254 calibration of phase transformation law given CCT Data LS-DYNA calculation 16

16 Selected features: phase transformation strain If Phase A and B have different density in case of phase transformation additional strain arises due to volume change: Phase Transformation Strain. 17

17 Simplified approach for single phase model *MAT_270 Heating Cooling 18

18 Validation Nitschke-Pagel test Distortion w: Experiment: 0,34 mm Sysweld: 0,32 mm LS-DYNA: 0,34 mm Loose, T.: Einfluß des transienten Schweißvorganges auf Verzug, Eigenspannungen und Stabiltiätsverhalten axial gedrückter Kreiszylinderschalen aus Stahl, Diss, Karlsruhe,

19 DynaWeld Management for high sofisticated welding and heat treatment materials Material DynaWeld Material User defined JMatPro Import and extensions: Base material phase Liquid material phase Tempering phase Flowcurve adjustment Welding settings LS-DYNA Material keyword-file multi phase *MAT_254 WeldWare other material simulation software LS-DYNA Material keyword-file singel phase *MAT_270 20

20 DynaWeld Material - Import Interfaces single phase multi phase Settings and Extensions 21

21 DynaWeld Material Documentation spreadsheet DynaWeld-Material-Check Graph for each material parameter 22

22 DynaWeld Foto: Edyta Łopatecka Heat Treatment 23

23 DynaWeld Management for high sofisticated heat treatment simulation setup Model Setup DynaWeld Heat Treatment Oven curve Carburization LS-DYNA Mesh keyword-file LS-DYNA Material keyword-file Dokumentation in spreadsheed format HT-Process HT-Parameter HT-Solver Settings LS-DYNA Keyword-files Quenching media Diving LS-DYNA solver run 24

24 DynaWeld Heat Treatment - Process 25

25 DynaWeld Heat Treatment - Parameter 26

26 DynaWeld Foto: Edyta Łopatecka Welding 27

27 Laser welded sheet with tensile test 28

28 DynaWeld Management for high sofisticated welding simulation setup Model Setup LS-DYNA Mesh keyword-file LS-DYNA Material keyword-file Dokumentation in spreadsheed format DynaWeld Welding Process Timestep adjustment Boundary and Clamps Parts, Material assignment Contact Solver Settings LS-DYNA Keyword-files Trajectory Heat Source Clamp Kinetic LS-DYNA solver run 29

29 DynaWeld Process Types of heat source surface heat source volumetric heat source part heating Start, end, intermediate time SimWeld interface Multi robots simultaneous Multiple heat source Geometric shapes elipsoid double elipsoid cylinder conus double conus Heat input on shell, shell 2D solid segment auto fill or copy option Reverse option Reorder of sequence Multi layered welds auto deactivation of not yet deposit material supports the new LS-DYNA heat source - on shells and solids - shell thickness distribution - engergy input control - sub cycling - mesh independent - time step independent 30

30 Weldpath definition - trajectory and reference Definition with one Nodeset auto detection of reference normal on surface Rotation of reference v-offset *BOUNDARY_THERMAL_WELD_TRAJECTORY Local adjustment: - rotation - v-offset reference direction - w-offset lateral v Local coordinate system heat source automatic calculation of the length of trajectory Display of trajectory, reference, startpoint x ce n e fer e R z Global coordinate system y u No k aje r T t Se e d t Se e od N y tor w-offset w u: Trajektory direction v: Torch direction w: Lateral direction 31

31 DynaWeld Boundary Single point constraints (SPC) Force or displacement driven clamps Symetry surfaces Force on Nodes or Node Sets force disp Displacement on Nodes or Node Sets Force or Displacement: user defined ramp at start and end local coordinate system Predeformation Prestress time Clamped force driven or displacement driven Clamping Unclamping 32

32 DynaWeld Contact mechanical and thermal Welding contact change friction tied by temperature Friction contact Tied contact Shell edge to surface or solid friction or tied contact mechanical Node to surface auto-correct of large penetration mechanical only Special features smooth option for curved sheets mortar option for implicit analysis shell thickness considered automatically 33

33 DynaWeld-Welding Input file generator Analysis Options Clean Work Directory Generate Input one file structured input single task creation Check options Run and Kill 34

34 DynaWeld Tools Create Variants Heat iput check Automatisation for results along path or time history at nodes Performance analyse Midpoint by 3 Points Conversion utilities Launch postprocessing file with DynaWeld temperature scale 35

35 Check of heat input and final adjustment right energy input right results 36

36 Conclusion LS-DYNA Material Models representing physics within phase kinetics from Process parameter to solver keyword input Succes in industrial applied simulation for manufacturing processes with high sophisticated phiysical phenomena like Heat Treatment and Welding DynaWeld 37

37 DynaWeld GmbH & Co. KG in Gründung Schweißstruktursimulation Schweißprozessimulation Wärmebehandlungsimulation Werkstoffsimulation Prozesskettensimulation # 38

38 Foto: Martin Loose 39