{ The rotational dynamics of nearly spherical and cylindrical tracers dissolved in supercooled o-terphenyl is studied via the Electron Spin Resonance spectroscopy. On decreasing the t emperature, a sharp crossover is observed from the regime w h ere the D e bye-Stokes-Einstein law (DSE) holds to a n ew one which is accounted for by a fractional DSE (FDSE) Dr / ( = T) ; with 1. Dr is the rotational di usion constant, the s h ear viscosity a n d T the t emperature. Tumbling a n d spinning o f t he c y l i n drical tracer exhibit distinct crossovers. A simple model of FDSE based on the presence of dynamic heterogeneities is presented.

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In this paper, the capability of laser powder bed fusion (L-PBF) systems to process stainless steel alloys is reviewed. Several classes of stainless steels are analyzed (i.e., austenitic, martensitic, precipitation hardening and duplex), showing the possibility of satisfactorily processing this class of materials and suggesting an enlargement of the list of alloys that can be manufactured, targeting different applications. In particular, it is reported that stainless steel alloys can be satisfactorily processed, and their mechanical performances allow them to be put into service. Porosities inside manufactured components are extremely low, and are comparable to conventionally processed materials. Mechanical performances are even higher than standard requirements. Micro surface roughness typical of the as-built material can act as a crack initiator, reducing the strength in both quasi-static and dynamic conditions.

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The reorientation of a nearly spherical paramagnetic tracer dissolved in supercooled o-terphenyl is studied by electron spin resonance in the range 200 K < T < 370 K. For T > 300 K the rotational correlation time τ 2 follows the Debye-Stokes-Einstein law. On decreasing the temperature, the rotational motion of the probe and the viscosity η decouple. In particular, in the region around T = 290 K it is found that τ 2 ∝ (η/T ) ξ with ξ = 0.28 ± 0.04.

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