MIT-World Peace University (MIT-WPU) is a top educational institute located in Pune, India. It is recognized within&nbsp;UGC under Government of Maharashtra Act No. XXXV 2017.&nbsp;

It is part of the MIT group of institutions (established in 1983) which covers 10+ campuses across India and has more than 50,000+ students enrolled across various disciplines at a given point of time. The institute houses 15 schools ranging from Engineering &amp; Technology, Design, Pharmacy, Commerce, Governance among others. It offers undergraduate, postgraduate and PhD programs among different disciplines.&nbsp;

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MIT World Peace University

This paper aims at investigating the effect of strain ratio on LCF behavior of dual phase (DP) steel at room temperature. LCF tests are generally performed at strain ratio of -1. In real life scenarios, cyclic loading does not usually correspond to fully reversed condition due to operational circumstances such as preload, duty cycle, vibrations or the environmental effects. Therefore, it becomes necessary to investigate the fatigue properties and LCF behavior for un-symmetric loading conditions as well. Dual Phase (DP) steels are extensively used in automotive industries owing to its large energy absorption capacity in the event of crash. Hence, evaluation of their LCF behavior becomes crucial. In this study, tests are carried out under strain-controlled conditions at two different strain ratios (-1 and 0.1) to investigate the LCF and mean stress relaxation behavior of a DP steel. Fractured surfaces of failed specimens are investigated under SEM to investigate its crack nucleation and propagation sites and to determine its failure mechanism. A correlation is established between fatigue properties at two strain ratios which can be extended for other grades of dual phase steels. © 2022 SAE International. All Rights Reserved.