Casting Defect Analysis and Optimization of an Internal Combustion Engine Piston using FEA

Abstract

This research investigates the impact of casting defects—particularly shrinkage and porosity—on the thermal and structural performance of aluminum pistons used in internal combustion engines. The study integrates CAD modeling via CATIA V5 with Finite Element Analysis (FEA) through ANSYS to evaluate piston behavior under high thermal stress. Three design iterations were examined: one without shrinkage, one with uniform shrinkage, and one with varying shrinkage. Results highlight that casting defects significantly raise stress concentrations, reduce fatigue life, and threaten component integrity. The study concludes with optimization recommendations and proposes advanced defect-mitigation strategies using future digital manufacturing technologies.

Introduction

Pistons face extreme thermal and mechanical loads, making defect-free casting critical for engine durability. This study examines how common casting defects (e.g., shrinkage, porosity) affect piston performance using simulation and material analysis.

Key Points:

1. Problem Statement & Objective:

• Casting defects compromise piston strength, especially under cyclic thermal stress.

• Objective: Simulate pistons with and without defects to assess structural impact and suggest manufacturing optimizations.

2. Literature Insights:

• Shrinkage is a leading cause of mechanical failure.

• FEA (Finite Element Analysis) and CFD (Computational Fluid Dynamics) are useful for defect prediction.

• Aluminum alloys like A356 are lightweight but sensitive to casting flaws.

3. Methodology:

• Three piston models were created in CATIA V5:

  • Baseline (no defects)

  • Uniform shrinkage

  • Localized shrinkage

• Models were simulated in ANSYS for thermal and structural analysis.

• Simulated casting temperature: 750°C.

4. Simulation Details (FEA):

• Material: A356 aluminum

• Yield Strength: 250 MPa

• Thermal Conductivity: 167 W/m•K

• Boundary Conditions:

  • Fixed at piston pin

  • Crown exposed to 750°C

  • Ambient temp: 25°C

5. Results:

• Baseline model: Max stress = 494.92 MPa

• Defective model: Max stress = 1098 MPa due to stress concentration at defects

• Fatigue life: Significantly reduced in defected models

Conclusion

This study concludes that casting defects critically affect piston performance. Simulation results validate the need for defect mitigation during casting. Implementing better mold design, controlled cooling, and defect-detection techniques can significantly enhance component reliability. The integration of simulation in early design phases helps in optimizing designs before physical manufacturing.

References

[1] Smith, J., et al. (2019). Casting Defects and Their Control in Aluminum Alloys. Journal of Materials Science. [2] Li, W., et al. (2020). Shrinkage Defects in Steel Casting. Materials Science and Engineering A. [3] Zhang, Y., et al. (2018). Porosity in Die Castings. International Journal of Cast Metals Research. [4] Kumar, R., et al. (2017). Cold Shut Defects in Casting. Journal of Casting & Solidification. [5] Wang, H., et al. (2021). Mold Design and Defect Control. Foundry Journal.

Copyright

Copyright © 2025 Manthan M Gaikwad, Shantanu M Mane, Aashish P Prajapati, Gayatri S Jagdale. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.