Correlation of Fractographic Features with Mechanical Properties in Systematically Varied Microstructures of Cu-Strengthened High-Strength Low-Alloy Steel

Abstract

Fracture is often the culmination of continued deformation. Therefore, it is probable that a fracture surface may contain an imprint of the deformation processes that were operative. In this study, the deformation behavior of copper-strengthened high-strength low-alloy (HSLA) 100 steel has been investigated. Systematic variation of the microstructure has been introduced in the steel through various aging treatments. Due to aging, the coherency, size, shape, and distribution of the copper precipitates were changed, while those of inclusions, carbides, and carbonitrides were kept unaltered. Two-dimensional dimple morphologies, quantified from tensile fracture surfaces, have been correlated to the nature of the variation of the deformation parameters with aging treatment.

The Effect of Gadolinium on the Microstructures and Charpy Impact Properties of Super Duplex Stainless Steels

“…In general, the larger and deeper the dimple, the better plastic properties [62,63]. These results are in accordance with a previous report that reveals the relationship between dimple structure and mechanical properties of steels [64]. Das et al confirmed that the ductility value of a copper-strengthened high-strength low-alloy (HSLA) was directly proportional to the diameter of dimples.…”

Characterization of micrographs and fractographs of Cu-strengthened HSLA steel using image texture analysis

“…The aforesaid mechanism has been earlier shown by Das [2] using transmission electron microscopic (TEM) images of Cu-strengthened HSLA steel. The variation of mechanical properties with ageing temperature for this class of steel has been earlier explained by Das et al [21] in terms of variation in void morphologies (average circular diameter of dimples, dimple number density, and dimple size distribution) estimated from the fractographs. These authors have shown earlier that by varying the size, coherency, and distribution of copper precipitates in the steel matrix through quench and ageing treatment, systematic variation in void nucleating sites can be obtained.…”

Advanced quantification of the carbide spacing and correlation with dimple size in a high-strength medium carbon martensitic steel

“…As for bcc iron alloys, dimple size distributions have been reported in HSLA steels [53,54] and in quenched and tempered steels [1,12]. All of them appeared asymmetrical but none of them was described with a mathematical distribution function.…”

“…As in e.g. [13,[53][54][55][56], image analysis was carried out to quantify the fractographic behavior of the three materials. At least seven images at magnification 2 × 10 4 (pixel size: 5 nm) were taken from different locations in this zone.…”