2000•The proceedings of the JSME annual meetingOpen access

Giga-Cycle Fatigue Properties of High Strength Steels : Part VII : Nanoscopic Analysis of High Strength Tempered Martensitic Steels

Kensuke Miyahara, Kaneaki Tsuzaki, Saburo MATSUOKA

Abstract

Hardness and microstructures of high strength tempered martensitic steels SUP12 were investigated using the nanoindentation tester and atomic force microscope. The ausformed steel, which has improved fatigue properties, has almost the same hardness as the conventional QT steel in both nanoscopic and macroscopic tests. Microstructural observation reveals the QT steel has 10μm-large lower bainites as defects that are not observed in the ausformed steel. The uniform microstructure is a possible reason for improvement in fatigue properties of the ausformed steel, in addition to absence of ODA (optically dark area) around inclusions.

Open-access reader

About this research paper

What this paper is about

Why it matters

A significance statement is not available in the OpenAlex record.

Key contribution

A contribution statement is not available in the OpenAlex record.

Method / approach

Method details are not available in the OpenAlex metadata.

Main findings

Findings are not separately available in the OpenAlex metadata.

Limitations

Limitations are not available in the OpenAlex metadata.

Applications

Application details are not available in the OpenAlex metadata.

Available abstract

Key concepts: Nanoindentation, Materials science, Martensite, Microstructure, Fatigue limit, Metallurgy, Nanoscopic scale, High strength steel