Effect of Strain Rate on the Deformation Behaviour of A356-T7 Cast Aluminium Alloys at Elevated Temperatures
Journal article, 2020

Internal combustion engine downsizing and powertrain electrification trends in recent years have led to higher thermal loads on the cylinder head materials with an increased number of engine start–stop thermal load cycles. This requires designing cylinder heads that are resilient against thermomechanical fatigue damage. To reduce the developmental costs, reliable numerical models for use in computer-aided design approaches are required. Thus, a comprehensive understanding of the material deformation behaviour under loads mimicking in-service conditions is desired to make better engineering decisions. This study examines the effect of strain rate on the cyclic deformation behaviour of the A356-T7 + 0.5% Cu aluminium alloy commonly used in modern internal combustion engine cylinder heads. Samples extracted from the valve bridge areas of the cylinder heads are tested in strain-controlled fatigue tests. Samples are tested at strain rates of 1% s−1 and 10% s−1 at room temperature, 150 and 200 °C. The material exhibits increased isotropic hardening and softening rates and an increased number of cycles to failure at 10% s−1. The strain rate has a dramatic influence on the mean stress development at room temperature. The role of silicon particles in the fracture mechanism is investigated using electron microscopy techniques.

fatigue

deformation behaviour

mechanical properties

A356

strain rate

cylinder head

aluminium

Author

Elanghovan Natesan

Chalmers, Industrial and Materials Science, Engineering Materials

Johan Ahlström

Chalmers, Industrial and Materials Science, Engineering Materials

Swathi Kiranmayee Manchili

Chalmers, Industrial and Materials Science, Materials and manufacture

Stefan Eriksson

Volvo Cars

Christer Persson

Chalmers, Industrial and Materials Science, Engineering Materials

Metals

2075-4701 (eISSN)

Vol. 10 9 1239

Development of analysis models for thermomechanical fatigue

Swedish Energy Agency, 2013-10-01 -- 2018-12-31.

Subject Categories

Materials Engineering

Applied Mechanics

Vehicle Engineering

Metallurgy and Metallic Materials

Areas of Advance

Transport

Materials Science

DOI

10.3390/met10091239

More information

Latest update

1/4/2021 8