A New Analytical Expression for the Relationship Between the Charpy Impact Energy and Notch Tip Position for Functionally Graded Steels

作者：Pour H Samareh Salavati^*; Berto F; Alizadeh Y

来源：Acta Metallurgica Sinica (English Letters), 2013, 26(3): 232-240.

DOI：10.1007/s40195-012-0241-y

• Charpy impact energy
• Functionally graded steel
• Crack divider configuration
• Crack arrester configuration

The effect of the distance between the notch tip and the position of the middle phase in the FGSs on the Charpy impact energy is investigated in the present paper. The results show that when the notch apex is close to the middle layer, the Charpy impact energy reaches its maximum value. This is due to the increment of the absorbed energy by plastic deformation ahead of the notch tip. On the other hand, when the notch tip is far from the middle layer, the Charpy impact energy strongly decreases. Another fundamental motivation of the present work is that for crack arrester configuration, no accurate mathematical or analytical modelling is available up to now. By considering the relationship between the Charpy impact energy and the plastic volume size, a new theoretical model has been developed to link the Charpy impact energy with the distance from the notch apex to the middle phase. This model is a simplified one and the effect of different shapes of the layers and the effect of microstructure on the mechanical properties and plastic region size will be considered in further investigation. The results of the new developed closed form expression show a sound agreement with some recent experimental results taken from the literature.

• 出版日期2013-6