Ramesh and Prabhu Nanoscale Research Letters 2011, 6:334 http://www.nanoscalereslett.com/content/6/1/334 with 1% of Al2O3 nanoscale particles [104]. It is evident that by adopting nanofluids as quenching media it is pos- sible to obtain the desired microstructure of components and hence the required mechanical properties. Summary Heat transfer and wetting kinematics are the two impor- tant phenomena during quenching that controls the final metallurgical and mechanical properties of the components. Judicious selection of quench medium is critical for obtaining optimum mechanical properties, avoiding quench cracks, minimizing distortion and improving reproducibility in hardening. The addition of nanoparticles to the conventional quenching fluid results in anomalous change in thermo-physical properties of the fluid, enhanced critical heat flux during boiling heat transfer, improved wetting characteristics and improved metallurgical and mechanical properties. 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