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ProCAST General Presentation
Typical Defects Predictions Validations Copyright © ESI Group, 2007 All rights reserved Density of metals vs temperature is not constant: Density, Kg/m3 Predicting Solidification Defect in Al HPDC– Shrinkage Porosity Temperature, °C Feeding problems during solidification: Courtesy of Kovolit, CZ Al HPDC Copyright © ESI Group, 2007 All rights reserved Predicting Solidification Defect in Cast Iron Sand Gravity– Cold Shot Copyright © ESI Group, 2007 All rights reserved Predicting Filling Defect in Zn HPDC–Die Erosion Copyright © ESI Group, 2007 All rights reserved Predicting Filling in Zn HPDC–Interrupted shot Copyright © ESI Group, 2007 All rights reserved Predicting Filling in Zn HPDC–Interrupted shot Copyright © ESI Group, 2007 All rights reserved Predicting Filling in Zn HPDC–Interrupted shot Copyright © ESI Group, 2007 All rights reserved Predicting Filling in Al Sand Casting-Coldshut prediction Vacuum forming Aluminium Silica Dry t = mm h = 400 mm d = 100 mm Copyright © ESI Group, 2007 All rights reserved Filling Validation Arbeitsgemeinschaft, Metallguss, Aalen (D) Copyright © ESI Group, 2007 All rights reserved Filling Validation Incomplete filling Copyright © ESI Group, 2007 All rights reserved Filling Validation Thixocasting validation Courtesy of Alusuisse Aluminium alloy (A356) Copyright © ESI Group, 2007 All rights reserved Filling Validation Thixocasting validation Aluminium alloy (A356) Courtesy of Austrian Research Centre Copyright © ESI Group, 2007 All rights reserved Microstructure Validation Copyright © ESI Group, 2007 All rights reserved Case Study AL HPDC Copyright © ESI Group, 2007 All rights reserved « Standard » Casting Simulation GEOMETRY PROCESS MATERIAL THERMAL & FLUID ANALYSIS THERMODYNAMIC DATABASES THERMO PHYSICAL PROPERTIES DEFECTS •FILLING DEFECTS •SOLIDIFICATION DEFECTS However, Shrinkage Porosity and Improper Fills are Important Defects predicted with Thermal And Fluid Analysis, but They Aren’t the Only Defects in Casting Processes… Copyright © ESI Group, 2007 All rights reserved “Cylinder” Model – NADCA Benchmark HPDC process / A383 Alloy Copyright © ESI Group, 2007 All rights reserved Guideline: Casting Modelling Phases Phase : Thermal cycling Phase : Filling (with extraction of thermal map at the end of cycling) Phase : Solidification (coupled with filling) Phase : Shrinkage and gas porosity Phase : Stress (coupled with filling and solidification) Phase : Microstructure and Mechanical Prop Copyright © ESI Group, 2007 All rights reserved Casting Modelling Phases Phase : Thermal cycling Phase : Filling (with extraction of thermal map at the end of cycling) Phase : Solidification (coupled with filling) Phase : Shrinkage and gas porosity Phase : Stress (coupled with filling and solidification) Phase : Microstructure and Mechanical Prop Copyright © ESI Group, 2007 All rights reserved Heat Up Cycles 15 Cycles Performed to Ensure Die Soak (Cavity Region Soaked in About 9, When Starting at 200 F) Regions Which Stay Warm are Indicated Copyright © ESI Group, 2007 All rights reserved Casting Modelling Phases Phase : Thermal cycling Phase : Filling (with extraction of thermal map at the end of cycling) Phase : Solidification (coupled with filling) Phase : Shrinkage and gas porosity Phase : Stress (coupled with filling and solidification) Phase : Microstructure and Mechanical Prop Copyright © ESI Group, 2007 All rights reserved OPTIMIZATION OF PISTON VELOCITY PROFILE 140 Two Shot Profiles Provided: 0.42m/s Slow Shot to m/s Fast Shot 0.23m/s Slow Shot to m/s Fast Shot Plunger Speed (ips) 120 100 80 60 40 20 0 0.2 0.4 0.6 Time (s) Copyright © ESI Group, 2007 All rights reserved 0.8 Air Entrapment Air Trapped In Sleeve Copyright © ESI Group, 2007 All rights reserved Filling MODELING MISRUNS, OXIDES, TURBULENCES, AIR ENTRAPMENT, VENTING POSITIONING… Copyright © ESI Group, 2007 All rights reserved Cold Fill Cold Fill As Shown In First Shot Cold Fill As Shown Even Into Further Cycles Copyright © ESI Group, 2007 All rights reserved Air Entrapment Filling Time Copyright © ESI Group, 2007 All rights reserved ... Group, 20 07 All rights reserved OPTIMIZATION OF PISTON VELOCITY PROFILE 140 Two Shot Profiles Provided: 0.42m/s Slow Shot to m/s Fast Shot 0 .23 m/s Slow Shot to m/s Fast Shot Plunger Speed (ips) 120 ... Speed (ips) 120 100 80 60 40 20 0 0 .2 0.4 0.6 Time (s) Copyright © ESI Group, 20 07 All rights reserved 0.8 Air Entrapment Air Trapped In Sleeve Copyright © ESI Group, 20 07 All rights reserved Filling... Centre Copyright © ESI Group, 20 07 All rights reserved Microstructure Validation Copyright © ESI Group, 20 07 All rights reserved Case Study AL HPDC Copyright © ESI Group, 20 07 All rights reserved