An improved Armstrong-Frederick-Type Plasticity Model for Stable Cyclic Stress-Strain Responses Considering Nonproportional Hardening

作者：Li, Jing^*; Zhang, Zhong-ping; Li, Chun-wang

来源：Journal of Materials Engineering and Performance, 2018, 27(4): 2038-2048.

DOI：10.1007/s11665-018-3271-4

• multiaxial fatigue
• nonproportional hardening
• non-proportionality factor
• plasticity incremental model
• stabilized stress-strain response

This paper modified an Armstrong-Frederick-type plasticity model for investigating the stable cyclic deformation behavior of metallic materials with different sensitivity to nonproportional loadings. In the modified model, the nonproportionality factor and nonproportional cyclic hardening coefficient coupled with the Jiang-Sehitoglu incremental plasticity model were used to estimate the stable stress-strain responses of the two materials (1045HR steel and 304 stainless steel) under various tension-torsion strain paths. A new equation was proposed to calculate the nonproportionality factor on the basis of the minimum normal strain range. Procedures to determine the minimum normal strain range were presented for general multiaxial loadings. Then, the modified model requires only the cyclic strain hardening exponent and cyclic strength coefficient to determine the material constants. It is convenient for predicting the stable stress-strain responses of materials in engineering application. Comparisons showed that the modified model can reflect the effect of nonproportional cyclic hardening well.

• 出版日期2018-4
• 单位西安电子科技大学; 中国人民解放军空军工程大学