PSI - Issue 69

Dezhen Yang et al. / Procedia Structural Integrity 69 (2025) 97–104

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Fig. 3. Ghost pearlite formed after quenching to room temperature from 750 °C austenitization, when the pearlite is formed at (a) 540 °C and (b) 570 °C. RA is retained austenite and M is martensite.

Fig. 4. The illustration of microstructural evolution. The quenched samples are tempered at 200 °C for 30 min to soften the hard and brittle martensitic matrix, as shown in Fig. 2(c-d). The tempered martensite matrix appears concave due to etching, while the film RA within the ghost pearlite retains its film-like morphology. The RA fraction decreases from 5.4 % to 5.1 % in 540 °C sample and