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

Understanding Low Cycle Fatigue Behavior of Alloy 617 Base Metal and Weldments at 900 °C

“…This behavior conforms well to a cyclic hardening characteristic, and is related to the accumulation of dislocation density within the matrix, γ, and the configuration of materials. As the LCF testing proceeds, the total dislocation density depends on the plastic strain accumulation (in accordance with the strain range), and the material resistance against the dislocation increases, while the stress amplitude continues to be slightly increasing [12]. …”

“…Again, as is seen from Figure 12, the fatigue striations on the weldment specimens are more obvious than on the base metal. The occurrence of fatigue striations was due to a repeated plastic blunting sharpening process arising from the slip of dislocations in the plastic zone of the fatigue crack tip [12]. However, the weldments could easily form fatigue striations and undergo quasi-cleavage facets due to their higher stress-strain interaction and being more brittle than that of the base metal [13].…”

Quantitative relationship between microstructure characteristics and fatigue parameters of A319 casting alloy

“…[1][2][3] Hence, lots of researches have been done on fatigue properties and their affecting factors of Al-Si casting alloys over the last decades. However, these components are usually subject to cyclic loadings during service which can cause initiation of fatigue crack, as well as failure of the whole structure.…”

“…Recently, considering the relationship between the monotonic tension and cyclic loading, Wang 18 proposed that one monotonic tension can be thought as a quarter of a cycle of cyclic loading, as shown in Equation (2) to (3), where σ f and ε f are the true stress and true strain of monotonic tension, respectively. The relationship between A f and A 0 is defined with ψ in Equation (4).…”

“…However, these components are usually subject to cyclic loadings during service which can cause initiation of fatigue crack, as well as failure of the whole structure. [1][2][3] Hence, lots of researches have been done on fatigue properties and their affecting factors of Al-Si casting alloys over the last decades. [4][5][6][7] Among all affecting factors, solidification cooling rate and modification of eutectic Si particles play an important role in controlling microstructure of Al-Si casting alloys which is closely related to alloy's properties.…”