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Fatigue Life Improvement through the “NOVA” Process
Technical Paper
2013-01-1400
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
The experimental methods focused on utilizing the newly
developed NOVA induction heating and hardening manufacturing
process as an adapted method to produce high performance engine
valve springs. A detailed testing plan was used to evaluate the
expected and theorized possibility for fatigue life enhancement. An
industry standard statistical analysis method and tools were
employed to objectively substantiate the findings. Fatigue cycle
testing using NOVA induction-hardened racing valve springs made of
ultra-high tensile material were compared to data for springs with
traditional heat treatment and those with standard processing.
The results were displayed using Wöhler and modified Haigh
fatigue life diagrams. The final analysis suggests that NOVA
processed springs have a seemingly slight, yet significant benefit
in fatigue life of 5 - 7% over springs processed through a
competing method. This improvement in fatigue life is a rather
precious advantage when considering high performance engine valve
springs and could result in up to a 10X improvement in actual
spring life, depending on the stress level of the field
application.
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Citation
Rababeh, M., Jawad, B., Alwerfalli, D., and Choucair, H., "Fatigue Life Improvement through the “NOVA” Process," SAE Technical Paper 2013-01-1400, 2013, https://doi.org/10.4271/2013-01-1400.Also In
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