Determination of microstructural parameters of CM186LC nickel-base superalloy using quantitative TEM

The microstructure of the superalloy CM186LC exhibits a pronounced dendritic character. The microstructure within the dendrite arms consists of cuboid γ′ precipitates, separated by narrow channels of γ matrix that contains nano-sized, spherical secondary γ′ precipitates. Between the dendrite arms, γ/γ′ eutectic areas and carbide particles could be observed. Quantitative microstructural investigations of the alloy were performed by means of transmission electron microscopy methods. The microstructural parameters, influencing the mechanical properties of the alloy (mean size of γ′ particles, mean particle spacing, shape coefficients of cuboidal γ′ precipitates and relative projection area), were determined.