Rejuvenation procedures to recover creep properties of nickel-base superalloys by heat treatment and hot isostatic pressing techniques

Reduction of micro-cracking in nickel superalloys processed by Selective Laser Melting: A fundamental alloy design approach

“…Hot Isostatic Pressing (HIP) can be used to consolidate cracks, however surface cracks and open porosity still remain [8]. In addition, the HIP process leads to coarsening of grains [9,10]. It is therefore argued that laser parameter control and/or post processing are not definitive solutions, and a more universal solution also requires the optimisation of the alloy during processing.…”

Microstructural evolution in damaged IN738LC alloy during various steps of rejuvenation heat treatments

“…Cavity nucleation is generally believed to commence at an early stage of creep deformation and continue during the creep life [22,29]. Thus, a number of cavities might be present in the damaged alloy that are too small to be detected via metallographic examination.…”

The γ′ precipitate rafting and element distribution during hot isostatic pressing in a nickel-based superalloy

“…Gamma prime (γ′), as the main precipitation-strengthening phase, is an L1 2 type order-FCC structure embedded in the FCC γ matrix. In practical engineering applications, the cubic γ′ particles will be converted into coarse and irregular morphology in addition to the flat shapes (e.g., γ′ rafting structure) due to the combination of high temperatures and complex stresses [4,5]. Such a γ′ rafting structure will directly affect the creep fatigue life of Ni-based superalloy.…”