Scanning electron microscope studies of fracture mechanisms of SAE 52100 bearing steel

Santos

et al. 2013

AMM

Martensitic high carbon high strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications where high wear resistance are required. Due to its high fatigue strength, SAE 52100 is recently being used not only for the production of bearings but also shafts. In this work, quenched SAE 52100 steel fatigue strength under rotating bending was investigated. Especially, we focus on “fisheye around inclusion” where the fatigue crack starts. Quantitative evaluation of its optical micrograph has not been enough carried out. In order to develop easy evaluation method for the fisheye area, we apply homology technique to the optical observation.

Section: Introductionmentioning

confidence: 99%

The Quantization of the Structure of Fisheyes via Homology Method

Nakane

Santos

et al. 2013

AMM

“…Martensitic high-carbon high-strength SAE 52100 bearing steel has been widely used as the main alloys for rolling contact applications and also other components bending and tension-compression applications. In the case of SAE 52100 steel bar specimen under long lasting low stress amplitudes, internal fatigue cracks called "fisheyes" originate mostly from subsurface inclusions in high carbon steel [1][2][3][4][5][6][7]. In order to improve the fatigue strength of machine components, the effect of repeated quenching on rotating bending life of SAE 52100 (JIS SUJ2) bars is investigated [8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Influence of Repeated Quenching-Tempering on Fisheye Cracks around Tin and Al2O3 Inclusions in SAE 52100 Steel

Honda

Koike

et al. 2013

AMM

Martensitic high-carbon high-strength SAE 52100 bearing steel has been widely used as the main alloys for rolling contact applications, and also at the components under bending and tension-compression. In order to enhance the material’s strength, refining the prior austenite grain size through repeated heating has been investigated. In this work, the microstructure of repeatedly quenched-tempered Ti, N-rich SAE 52100 steel was investigated. The material was melted by an electric furnace and formed by continuous casting and forging, and the crack origin on the fracture surface was investigated. It was found that repeated furnace quenching and tempering effectively refined the martenstic structure.

“…Failure in high carbon steel components under high-stressed rotating bending occurs at the material's surface until 1.0×10 4 or 10 5 cycles [1,2]. On the other hand, when the components are exposed to long lasting low stress amplitudes, internal fatigue cracks called "fisheyes" originating mostly from subsurface inclusions [3][4][5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Observation of Fisheye Cracks around TiN and Al2O3 Inclusions in Repeatedly Quenched High Carbon Bearing Steel

Honda

Koike

et al. 2012

AMR

Martensitic high-carbon high-strength SAE 52100 bearing steel is one of the main alloys used for rolling contact applications where high wear resistance is required. Refining the prior austenite grain size through repeated heating is a process commonly used to enhance the material’s strength. In this work, the microstructure of repeatedly quenched Ti, N-rich ultra-clean SAE 52100 steel was investigated. The material was melted by an electric furnace and formed by continuous casting and forging, and the crack origin on the fracture surface was investigated. It was found repeated furnace quenching effectively refined the martenstic structure.