Version 1
: Received: 30 October 2017 / Approved: 30 October 2017 / Online: 30 October 2017 (10:22:24 CET)
How to cite:
Baohua, N.; Zihua, Z.; Yongzhong, O.; Dongchu, C.; Hong, C.; Haibo, S.; Shu, L. Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy. Preprints2017, 2017100182. https://doi.org/10.20944/preprints201710.0182.v1
Baohua, N.; Zihua, Z.; Yongzhong, O.; Dongchu, C.; Hong, C.; Haibo, S.; Shu, L. Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy. Preprints 2017, 2017100182. https://doi.org/10.20944/preprints201710.0182.v1
Baohua, N.; Zihua, Z.; Yongzhong, O.; Dongchu, C.; Hong, C.; Haibo, S.; Shu, L. Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy. Preprints2017, 2017100182. https://doi.org/10.20944/preprints201710.0182.v1
APA Style
Baohua, N., Zihua, Z., Yongzhong, O., Dongchu, C., Hong, C., Haibo, S., & Shu, L. (2017). Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy. Preprints. https://doi.org/10.20944/preprints201710.0182.v1
Chicago/Turabian Style
Baohua, N., Sun Haibo and Liu Shu. 2017 "Effect of LCF Pre-Damage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy" Preprints. https://doi.org/10.20944/preprints201710.0182.v1
Abstract
The effect of low cycle fatigue (LCF) pre-damage on the subsequent very high cycle fatigue (VHCF) behavior is investigated in TC21 titanium alloy. LCF pre-damage is applied under 1.8% strain amplitude up to various fractions of the expected life and subsequent VHCF properties are determined using ultrasonic fatigue tests. Results show that 5% of LCF pre-damage insignificantly affects the VHCF limit due to the absent of pre-crack, but decreases the subsequent fatigue crack initiation life estimated by Pairs’ law. Pre-cracks introduced by 10% and 20% of LCF pre-damage significantly reduce the subsequent VHCF limits. The crack initiation site shifts from subsurface-induced fracture for undamaged and 5% of LCF pre-damage specimens to surface pre-crack for 10% and 20% of LCF pre-damage specimens in very high cycle region. The fracture mechanism analysis indicate that LCF pre-crack will re-start to propagate under subsequently low stress amplitude when stress intensity factor of pre-crack is larger than its threshold. Furthermore, the predicted fatigue limits based on EI Haddad model for the LCF pre-damage specimens well agree with the experimental results.
Keywords
very high cycle fatigue; fatigue pre-damage; titanium alloy; LCF
Subject
Engineering, Mechanical Engineering
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.