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In the work developed in this paper, the model of the microstructural behavior of Inconel 718 for the rotary forging process is studied. This process is presented as an alternative to the conventional forging. The window process of Inconel 718 is very narrow, so the requirements for manufacturing Inconel are very restrictive. Optimization of the rotary forging process was carried out in order to manufacture Inconel pieces with good microstructural distribution. Microstructural specification was given by aeronautic sector. Numerical work was done in order to simulate the microstructural behavior during the forming process. This method was used: a) to understand the recrystallization mechanism that take place in rotary forging processes, b) to compare the microstructure between a piece done in conventional forging and another done in rotary forging and c) to study the influence of the initial grain size in the final piece.

Microstructural behaviour of Inconel 718 using rotary forging as forming process is presented in this paper. This work is the continuation of a previous one, presented in ESAFORM 2012, in which the numerical model was described and previous results about microstructural behaviour were shown. Several simulations are carried out in order to investigate the effect of initial grain size, temperature and strain rate in microstructure. Experimental tests are done in order to validate the numerical results, analyzing the final microstructure. Preparation of the experimental equipment is shown: heating tool system, thermal isolation technique, tool design for the integration of the heating and the isolation system. Heat loss during the transfer operation between furnace and rotary forging machine is measured experimentally, in order to obtain a precise initial temperature value of the part at the beginning of the process. The experimental tests allow validating the simulation work, obtaining the real input parameters for the numerical calculation. Two ways of forming are obtained depending on the initial grain size. The optimal combination of the rotary forging process parameters listed above is determined in achieving a fine and homogeneous microstructure.

Superhydrophobic (SHP) and oleophobic aluminum surfaces have been prepared through the combination of a scalable chemical microtexturing process and surface functionalization with long-chained polyfluoroalkyl moieties. The effect of an anodic layer on the microtextured surface has been assessed considering surface morphology, superhydrophobicity, surface mechanical properties and corrosion protection enhancement. The surface functionalization with polyfluoroalkyl moieties has been tackled in two different ways: (i) grafting of the polyfluoroalkyl moieties and (ii) deposition of a thin hybrid coating with low content of polyfluoroalkyl-containing compound. Aluminum surfaces showing high durability in salt spray environments, which maintain SHP and oleophobic properties at least up to 2016 h have been attained. Applications for this kind of surfaces range from easy-to-clean surfaces to anti-icing or anti-condensation functionalities that could be of interest for several sectors.