Issue 66

A. Shelar et alii, Frattura ed Integrità Strutturale, 66 (2023) 38-55; DOI: 10.3221/IGF-ESIS.66.03

Tempered martensite laths

Hardened + Double Tempering (T2)

Lath width increases

Hardened + Third Tempering (T3)

Alloy carbide visible

Hardened + Fourth Tempering (T4)

10 12 14

0 2 4 6 8

Min Max Average

Lath Size (µm)

120 240 360 480 Tempering Time (min)

b) c) Figure 7: a) Surface morphology and EDS of specimen of Untreated H13 steel, T1, T2, T3, T4 b) Variation of Lath size vs. tempering time c) Change in phases during each tempering cycle.

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