ISIJ International
Online ISSN : 1347-5460
Print ISSN : 0915-1559
ISSN-L : 0915-1559
Regular Article
Influence of Hydrogen on Fatigue Property of Suspension Spring Steel with Artificial Corrosion Pit after Multi-step Shot Peening
Manabu Kubota Takahisa SuzukiDaisuke HirakamiKohsaku Ushioda
Author information
JOURNAL OPEN ACCESS FULL-TEXT HTML

2015 Volume 55 Issue 12 Pages 2667-2676

Details
Abstract

In order to reduce the weight of the suspension springs by increasing the strength level of the steels used, improvement of the corrosion fatigue property is the most important issue. This study investigated, the effect of residual stress, artificial corrosion pit depth and diffusible hydrogen on rotary bending fatigue properties of specimens after double shot and triple shot peening. The following conclusions were obtained:
(1) Fatigue limits of specimens having the artificial corrosion pit of 250 µm depth with and without the charged hydrogen are improved remarkably by the triple shot peening.
(2) Fish-eye fatigue fracture with an inclusion as the fatigue crack initiation site occurs frequently due to the charged hydrogen.
(3) A good relationship between fatigue limit after shot peening and compressive residual stress at the bottom of the artificial corrosion pit is obtained regardless of the depth of the artificial corrosion pit.

Effect of number of shot peening on fatigue limit of hydrogen-uncharged specimens and hydrogen-charged specimens as a function of artificial corrosion pit depth. [H] stands for hydrogen-charged specimens. Fullsize Image
Content from these authors
© 2015 by The Iron and Steel Institute of Japan
Previous article Next article
feedback
Top