Fatigue Life Prediction of Stainless Steel Laser Lap Joints Based on Natural Frequency Changes

Abstract:

In this paper, fatigue damage and life prediction of laser lap joints were investigated based on natural frequency as the damage variable. At each fatigue stage, damage degree of laser welded specimen was monitored by the fatigue test and dynamic response tests. The results show that in the fatigue process during the increase in the number of fatigue cycles, each order natural frequency of test specimen decreased at different rate. There was almost no damage before the number of cycles reached 60% of the fatigue life, and then cracks began to initiate. When the number of cycles reaches 80% of the life, macroscopic cracks appeared and the predicted damage degree reached to 50%. Based on relation between the change rate of the natural frequency and the fatigue damage, a new fatigue life prediction model was established. The results from experimental tests were consistent with the fatigue life prediction model.

• Periodical: Materials Science Forum (Volume 762)
• Pages: 680-685
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.762.680
• Online since: July 2013
• Authors: Chun Yuan Shi, Lan Zhan, Hong Xiao Wang, Chun Sheng Wang, Wei Yang
• Keywords: Fatigue Damage, Laser Lap Welding, Life Prediction, Natural Frequency

References

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