Experimental investigation of the damage characteristics of two cast aluminium alloys: Part I – Temperature dependent low cycle and thermomechanical fatigue behavior

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Abstract

Detailed material investigations of the fatigue behavior of two cast aluminium alloys used in combustion engines are presented. The network of intermetallic phases of both aluminium alloys is characterized by means of detailed energy dispersive X-ray spectroscopy. In order to investigate the temperature-dependent fatigue behavior of the materials, tensile, low cycle and thermomechanical fatigue tests are performed over a wide temperature and loading range. The influence of the temperature dependence on the experimental results is discussed.

Section snippets

Introduction and overview

Regarding the ecology of combustion engines, the present development and design is focused on the reduction of mileage and nitrogen oxides. The fuel efficiency is achieved by more efficient and highly loaded engines as well as by a lighter vehicle design. In many parts of combustion engines cast aluminium-silicon alloys are used, e.g. cylinder heads, pistons and engine blocks [1], [2]. The class of cast aluminium materials exhibits a high light weight potential due to its low density combined

Microstructure characterization and experimental details

In this chapter, the investigated materials and their specific microstructure are introduced in Section 2.1. The identification of the intermetallic phases is presented in Section 2.2. Further microstructural descriptors are determined in Section 2.3. Details of the test setup for the different experiment types are described in Section 2.4.

Basic material characterization

The cylinder head and piston cast aluminium alloys are characterized with regards to their temperature dependent fatigue properties. Tensile tests, isothermal complex low cycle fatigue (CLCF) and non-isothermal thermomechanical fatigue (TMF) tests were performed under strain control. The test results are used to calibrate and validate time and temperature dependent plasticity and lifetime models, which will be published in the future.

Temperature-dependence of isothermal Woehler curves

While the isothermal lifetimes in Fig. 13a of the cylinder head alloy AlSi7Cu0.5Mg-T7 alloy are hardly affected by the testing temperature for all investigated mechanical strain amplitudes, the isothermal lifetime behavior of the piston alloy AlSi12Cu3Ni2Mg-T7 in Fig. 13b is found to be strongly dependent on the temperature and the applied mechanical loading. Based on the observations above, it is assumed that the material’s specific microstructural behavior influences the mechanism of crack

Conclusions

In order to characterize the fatigue behavior of two cast aluminium alloys used for cylinder heads and pistons in combustion engines, tensile, low cycle and thermomechanical fatigue tests were performed over a wide temperature and loading range. The results are concluded as follows:

  • Microstructural investigations using light microscopy and energy dispersive X-ray spectroscopy show, that the cylinder head alloy AlSi7Cu0.5Mg-T7 exhibits a finer microstructure in terms of silicon particle and pore

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

The authors greatly acknowledge the financial support of the industrial collective research program (IGF No. 18921 N) supported by the Federal Ministry for Economic Affairs and Energy (BMWi) through the AiF (German Federation of Industrial Research Associations eV). Special thanks go to Karin Hintz for assisting during the EDX measurements and performing the metallographic and fractographic analyzes.

References (96)

  • X.F. Liu et al.

    Finite element analysis of thermo-mechanical conditions inside the piston of a diesel engine

    Appl Therm Eng

    (2017)
  • M.S. Song et al.

    Cyclic stress–strain behavior and low cycle fatigue life of cast A356 alloys

    Int J Fatigue

    (2011)
  • A.R. Emami et al.

    Cyclic deformation behavior of a cast aluminum alloy

    Mater Sci Eng A

    (2009)
  • D.D. Tian et al.

    Low cycle fatigue behavior of casting A319 alloy under two different aging conditions

    Mater Sci Eng A

    (2016)
  • M. Azadi et al.

    Heat treatment effect on thermo-mechanical fatigue and low cycle fatigue behaviors of A356.0 aluminum alloy

    Mater Des

    (2013)
  • W.W. Bose-Filho et al.

    Al–Si cast alloys under isothermal and thermomechanical fatigue conditions

    Int J Fatigue

    (2007)
  • J. Liu et al.

    Microstructure evolution of Al–12Si–CuNiMg alloy under high temperature low cycle fatigue

    Mater Sci Eng A

    (2013)
  • M. Wang et al.

    Low-cycle fatigue properties and life prediction of Al-Si piston alloy at elevated temperature

    Mater Sci Eng A

    (2017)
  • S. Tabibian et al.

    Behavior, damage and fatigue life assessment of lost foam casting aluminum alloys under thermo-mechanical fatigue conditions

    Procedia Eng

    (2010)
  • M. Wang et al.

    Thermo-mechanical fatigue behavior and life prediction of the Al-Si piston alloy

    Mater Sci Eng A

    (2018)
  • V. Firouzdor et al.

    Effect of microstructural constituents on the thermal fatigue life of A319 aluminum alloy

    Mater Sci Eng A

    (2007)
  • C. Fischer et al.

    Experimental investigation of the damage characteristics of two cast aluminium alloys: Part II – LCF/HCF and TMF/HCF loading with special focus on the short crack growth behavior

    Int J Fatigue

    (2021)
  • C. Fischer et al.

    Experimental investigation of the damage characteristics of two cast aluminium alloys: Part III – Influence of the local microstructure and initial defect size on the fatigue properties

    Int J Fatigue

    (2021)
  • R. Fernández-Gutiérrez et al.

    The effect of spheroidisation heat treatment on the creep resistance of a cast AlSi12CuMgNi piston alloy

    Mater Sci Eng A

    (2014)
  • N.A. Belov et al.

    Constituent phase diagrams of the Al–Cu–Fe–Mg–Ni–Si system and their application to the analysis of aluminium piston alloys

    Acta Mater

    (2005)
  • F.C. Robles Hernández et al.

    Thermal analysis and microscopical characterization of Al–Si hypereutectic alloys

    J Alloy Compd

    (2006)
  • S. Belmares-Perales et al.

    Addition of iron for the removal of the α-AlFeSi intermetallic by refining of β-AlFeSi phase in an Al–7.5Si–3.6Cu alloy

    Mater Sci Eng B

    (2010)
  • A.R. Farkoosh et al.

    Enhanced mechanical properties of an Al–Si–Cu–Mg alloy at 300 °C: Effects of Mg and the Q-precipitate phase

    Mater Sci Eng A

    (2015)
  • P. Huter et al.

    High- and low-cycle fatigue influence of silicon, copper, strontium and iron on hypo-eutectic Al–Si–Cu and Al–Si–Mg cast alloys used in cylinder heads

    Int J Fatigue

    (2016)
  • J.A. Taylor

    Iron-containing intermetallic phases in Al-Si based casting alloys

    Procedia Mater Sci

    (2012)
  • Z. Ma et al.

    A study of tensile properties in Al–Si–Cu and Al–Si–Mg alloys: Effect of β-iron intermetallics and porosity

    Mater Sci Eng A

    (2008)
  • J.Y. Hwang et al.

    The effects of Mn additions on the microstructure and mechanical properties of Al–Si–Cu casting alloys

    Mater Sci Eng A

    (2008)
  • Z. Qian et al.

    Effects of trace Mn addition on the elevated temperature tensile strength and microstructure of a low-iron Al–Si piston alloy

    Mater Lett

    (2008)
  • S. Manasijevic et al.

    Thermal analysis and microscopic characterization of the piston alloy AlSi13Cu4Ni2Mg

    Intermetallics

    (2011)
  • Y.J. Li et al.

    Influence of Cu on the mechanical properties and precipitation behavior of AlSi7Mg0.5 alloy during aging treatment

    Scripta Mater

    (2006)
  • J.Y. Hwang et al.

    The effect of Mg on the structure and properties of Type 319 aluminum casting alloys

    Acta Mater

    (2009)
  • G. Sha et al.

    Solute nanostructures and their strengthening effects in Al–7Si–0.6Mg alloy F357

    Acta Mater

    (2012)
  • Y. Yang et al.

    Evolution of nickel-rich phases in Al–Si–Cu–Ni–Mg piston alloys with different Cu additions

    Mater Des

    (2012)
  • C.-L. Chen et al.

    The combined use of EBSD and EDX analyses for the identification of complex intermetallic phases in multicomponent Al–Si piston alloys

    J Alloy Compd

    (2010)
  • Z. Asghar et al.

    Three-dimensional rigid multiphase networks providing high-temperature strength to cast AlSi10Cu5Ni1-2 piston alloys

    Acta Mater

    (2011)
  • Y. Sui et al.

    Effects of Sr content on the microstructure and mechanical properties of cast Al–12Si–4Cu–2Ni–0.8Mg alloys

    J Alloy Compd

    (2015)
  • M. Warmuzek

    Chemical composition of the Ni-containing intermetallic phases in the multicomponent Al alloys

    J Alloy Compd

    (2014)
  • Y. Li et al.

    Quantitative comparison of three Ni-containing phases to the elevated-temperature properties of Al–Si piston alloys

    Mater Sci Eng A

    (2010)
  • C. Garb et al.

    Application of modified Kitagawa-Takahashi diagram for fatigue strength assessment of cast Al-Si-Cu alloys

    Int J Fatigue

    (2018)
  • C. Garb et al.

    Fatigue strength assessment of AlSi7Cu0.5Mg T6W castings supported by computed tomography microporosity analysis

    Procedia Eng

    (2016)
  • D.L. McDowell et al.

    Microstructure-based fatigue modeling of cast A356-T6 alloy

    Eng Fract Mech

    (2003)
  • M. Wang et al.

    Deformation mechanism and fatigue life of an Al-12Si alloy at different temperatures and strain rates

    Int J Fatigue

    (2019)
  • T. Beck et al.

    Damage mechanisms of cast Al–Si–Mg alloys under superimposed thermal–mechanical fatigue and high-cycle fatigue loading

    Mater Sci Eng A

    (2007)
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