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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.

Magnesium is sought to be one of the futuristic material in automotive due to its superior properties such as density, strength to weight ratio, damping characteristics and thus, making it a key enabler for light weighting. The properties of Magnesium alloys can be widely altered by change in elemental composition and heat treatment. Analysis of composition and phase morphology are driving factors for determining component’s end use properties and can be utilized effectively in its product development cycle. The as-cast AZ series alloys develop microstructure consisting of α-Mg matrix, eutectic α-Mg/γ-Mg17Al12 phase with non-uniform Al solute content in the α-Mg. Solutionising causes dissolution of Mg17Al12 brittle phase thereby increasing strength and ductility in these alloys. This paper presents analysis of AZ series automotive alloy components with focus on microstructure and mechanical properties change after solutionising.

Castings by virtue of their manufacturing process route are prone to induce various defects which are likely to affect adversely during its service life, causing pre-mature failures. Multiple destructive and non-destructive evaluation techniques are practiced to analyze these defects and suitable measures are taken to ensure quality castings and avoid pre-mature failures. Accurate detection for each type of defect is key factor during analysis to adopt desired modifications in process and /or product stage.

Used oil analysis plays an important role in the field of engine development, considering that it can give brief idea about performance of lubricant/ oil being used, its compatibility with the system under considerations. At present, regular testing is done like elemental analysis using Inductive Coupled Plasma (ICP) which can give idea about wear elements and additive elements. But it does not give information on morphological characterization of particles. In present work, Environmental Scanning Electron Microscopy technique with EDAX detector is used for characterizing the used oil. Oil is filtered on suitable paper and the particles collected on paper are analyzed. This gives the information on morphology and size of particles, their elemental analysis and mapping so that the sources can be judged. Size of wear metal particle is very important factor as even few bigger size particles are more detrimental than large number of smaller particles.