Fractographic Study on the Fatigue Failure Surfaces of Heat-Treated and Shot Peened EN- 8 Steel (080M40/AISI 1040)
FRACTOGRAPHIC ANALYSIS ON FATIGUE SURFACE OF HEAT- TREATED AND SHOT PEENED EN-8
DOI:
https://doi.org/10.56042/ijems.v30i4.961Keywords:
Fractography, Microstructure, Fatigue, Quenching & Tempering (Q&T), Without Treated (WT), Shot Peening (SP), Scanning Electron Microscope (SEM), EN-8(080M40/ANSI 1040) SteelAbstract
The microstructure study has been carried out on the fatigue fractured surface of heat-treated and shot peened EN-8 (080M40/AISI 1040) steel. This microstructure study reveals the characteristic appearance and physical arrangement of a metal as observed with a microscope. In order to realize the initiation and progression of fatigue failure, the fractured surface could be analyzed with the Scanning Electron Microscope (SEM). In this present work, the different categories of heat-treated and shot-peened fatigue fractured samples were involved in the fractographic investigation such as WT, Q&T, SP and combined Q&T and SP. For probing the fractured surface, SEM images have been taken with different magnification (16X, 100X, 249X and 500X) in VEGA3 TESCAN Scanning Electron Microscope for each category sample having fractured bending stress value of 293.45MPa. It was found that the combined Q&T and SP sample has fractured at the interface of a granular region and beach marks are spread over the fractured surface. The result of Q&T and SP sample fractured surface analysis concluded as that the brittle fracture with inter-granular cracks are formed due to relieving of residual stresses at the surface of the samples obtained from combined treatments.
