Investigating the influence of residual stresses on fatigue crack growth for additively manufactured titanium alloy Ti6Al4V by using peridynamics

Titanium alloy corrosion fatigue crack growth rates prediction: Peridynamics based numerical approach

“…However, such methods become invalid in the presence of field's discontinuities such as cracks, and a new continuum mechanics theory, named Peridynamics [27], was introduced to overcome this limitation. PD is based on integro-differential equations and proved its applicability on fatigue crack nucleation [28], propagation problems in metals [29,30] and composites [31] and on corrosion problems [32,33]. The current research will also show the applicability of the PD tool on the CF problems.…”

“…As discussed in [48], the difference between the cast/wrought and additively manufactured Ti6Al4V alloys is the anisotropy of additively manufactured alloys, for example, when the load is applied parallel or perpendicular to the built direction. The anisotropy can be a consequence of residual stresses [30], defects and columnar grains in the additively manufactured materials. Each factor in the structure contributes to reduced fatigue properties and decreases the fatigue life.…”

Numerical simulation of the effect of surface microgeometry and residual stress on conformal contact fretting fatigue crack initiation behavior

“…Generally, tensile residual stress, which is generated on the machined surface due to the low thermal conductivity of titanium alloys 38 and excessive temperature gradients on the machined surface, 36 is considered unfavorable for the component's service performance. Conversely, compressive residual stresses can significantly increase the service performance 39–42 . Note that the effect of residual stress on fatigue life is a dynamic process, 25 which means residual stress relaxation cannot be ignored in the prediction of fatigue life.…”

“…Conversely, compressive residual stresses can significantly increase the service performance. [39][40][41][42] Note that the effect of residual stress on fatigue life is a dynamic process, 25 which means residual stress relaxation cannot be ignored in the prediction of fatigue life.…”

Study on Residual Stress in Disc-Milling Grooving of Blisks

“…In titanium alloy additive manufacturing, high residual stresses can exist in the sample due to layer-by-layer fabrication, which can affect the fatigue strength of the product. Karpenko et al [ 10 ] proposed a numerical method to predict the effect of residual stresses on the fatigue crack expansion rate (FCGR) and verified the validity of the method experimentally. Kyaramyan et al [ 11 ] proposed several parameters for the combined surface heat treatment and air shot peening machining process of VT41 titanium alloy compressor impeller blades for advanced engines and analyzed the residual stresses in the initial state of the blades and after finishing treatment to derive the effects of each parameter on the microstructure and life of the blades.…”