Analysis Of The Fatigue Behavior Of NST 37-2 Steel Based On Probabilistic Stress-Life (P-S-N) Relationships

B.O. Malomo; S.A. Ibitoye; L.O. Adekoya

B.O. Malomo Departments of Mechanical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria.
S.A. Ibitoye Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria.
L.O. Adekoya Departments of Mechanical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria

Keywords: Fatigue behavior, Probability-stress-life, Weibull plot, Steel

Abstract

A new data analysis method proposed by Shimizu et al. (2010) which defines the physical meaning of the statistical parameters in the Weibull distribution function based on the theoretical consistency between material life distributions and probabilistic stress life (P-S-N) curves was applied in this study to analyze the fatigue behavior of locally-rolled NST 37-2 steel. Tensile tests were carried out to establish the baseline material properties of the steel. Fatigue tests were conducted at 60-80% S_u of the test material and then fractured surfaces were examined. Weibull plots were obtained through linearized transformations and compared with representative relations from the proposed new method of analysis. The results obtained showed a non-conservative trend in the classification of the fatigue performance of the test material in as-rolled, annealed, normalized and hardened/tempered conditions. Thus, test material may be useful in low cycle quasi-static applications.

Author Biographies

B.O. Malomo, Departments of Mechanical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria.

Departments of Mechanical Engineering,

Obafemi Awolowo University, Ile-Ife, Nigeria.

S.A. Ibitoye, Materials Science and Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria.

Materials Science and Engineering,

Obafemi Awolowo University, Ile-Ife, Nigeria.

L.O. Adekoya, Departments of Mechanical Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria

Departments of Mechanical Engineering,

Obafemi Awolowo University, Ile-Ife, Nigeria

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