Characterization of shear stresses in nickel-based superalloy Mar-M247 when orthogonal machining with coated carbide tools

A holistic approach to Thermo-Mechanical Fatigue phase angle effects for an aerospace nickel superalloy

“…Evidence of this has previously been shown [11]. For RR1000, isothermal fatigue at 650°C shows evidence of slip bands and dislocation climb [25] resulting in transgranular cracking along the {111} plane arising from localised planar deformation. Considering the crack paths shown for each phase angle, as presented in Figure 6, it becomes possible to describe the effect of phase angle and oxidation.…”

“…Previously mentioned, work by Guth et al [14] on Mar-M247 featured life data for Δε=0.3-0.6% IP, 90CW, 90ACW and OOP with T=100-850°C. Using temperature dependant elastic modulus data from [25] and [26] the described procedure was conducted to predict the life of the 90CW/90ACW life as shown in Figure 13. The model more accurately predicts the 90CW/90ACW life to be greater than the IP and OOP over the same strain range.…”