The effect of surface finish on the low cycle fatigue of medium carbon steel

Date

2024-10

Journal Title

Journal ISSN

Volume Title

Publisher

Federal University of Technology, Owerri

Abstract

As fatigue cracks initiate predominantly at the free surface of a material, the condition of the surface can be assumed to be critical with regards to fatigue strength. The features of a mechanically prepared surface which are considered to be major factors affecting fatigue strength fatigue are stress concentration (a shape factor), dimension (a scale factor), and surface finish (a technological factor). This paper investigates the effect of surface finish on the fatigue life of AISI/ SAE 1040 (medium carbon steels). A compositional analysis was performed to ascertain the percentage of carbon in the materials. The specimens were machined to a precise gauge length and diameter and exposed to various surface finishes mainly; polishing and grinding machining surface conditions. A fatigue test was performed with the use of Avery Dennison and bending stress was obtained using the curve supplied with the machine. The results from the machine were converted to Mega Pascal (MPa) and the values used to plot S-N curves. The fatigue resistance for the specimens at various surface finishes of the different carbon steels was thus established. The results show that the polished surface with surface roughness (Ra = 0.20microns) has the longest fatigue life.

Description

This conference paper contains tables and figures

Keywords

Surface finish, fatigue, medium, carbon steel, machining

Citation

Obiukwu, O. O., Nwafor, O. M. I., Okafor, B. & Osueke, G. (October, 2014). The effect of surface finish on the low cycle fatigue of medium carbon steel. Paper presented at the International Conference of the Nigerian Institute of Industrial Engineers, Ibadan, Nigeria

DOI