Process investigation and mechanical properties of electro sinter forged (ESF) titanium discs

Abstract

 Users may download and print one copy of any publication from the public portal for the purpose of private study or research.  You may not further distribute the material or use it for any profit-making activity or commercial gain  You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.

Maintenance and testing protocols in the railway industry

“…If possible, in this phase, specific outputs should be assumed to be the 'fingerprints' of the process. This approach has also been followed by other research concerning similar manufacturing engineering fields [32], [33]. These outputs may provide information on how best to conduct the restoration process, and, if the values measured are out-of-range, they can trigger proper actuation controls that enable the correction of the previously set process parameters, as suggested in Figure 3.…”

“…This is particularly difficult if there is no structure or schedule for these activities, even if it may not appear relevant at first sight. Focusing on an industry working with train-part processing [32] and testing as a case study, we apply the proposed protocols to the turning processes and pneumatic testing of train braking systems using digitised traceability (see scheme in Figure 1). The proposed protocols are based on the concepts described in the state-of-the-art, which includes the new auto-adaptive intelligent control facilities and an actuation process improved by artificial intelligence (AI), as set out in Figure 2.…”

“…Study case[32]: (a) functional scheme of the layout designed for industrial traceability; (b) optical sensor system that estimates accuracy in turning processes; (c) schematic layout of the bench designed for the pneumatic testing of train braking systems.…”

Influence of Processing Parameters on the Conduct of Electrical Resistance Sintering of Iron Powders

“…Among the ERS advantages, in comparison with the conventional PM cold-pressing and furnace sintering route, the use of relatively low pressures (around 100 MPa) to achieve very high densities, the use of extraordinarily short processing times (around 1 s), and the possibility of operating in the air, without protective atmospheres, can be mentioned. Some recent works dealing with this modality can be found in [15][16][17]. In these works, a process conceptually similar to the ERS technique was successfully applied to iron-base materials, gold, silver tin oxide, titanium, or rare-earth magnets.…”

Nickel Porous Compacts Obtained by Medium-Frequency Electrical Resistance Sintering

“…Comparing the ERS technique with the conventional powder metallurgy (P/M) route of cold-pressing and furnace sintering, three aspects are noteworthy: (i) the high densification rates achieved with the ERS at low pressures (around 100 MPa), (ii) the very short processing times (around 1-2 s), and (iii) the possibility of not using protective atmospheres, as a consequence of (ii). However, the usual non-homogeneous temperature distribution, inside the compacts, during ERS (or a similar technique) makes it difficult to achieve a homogeneous microstructure (and isotropic properties) throughout the compact [8][9][10][11]. In addition, finding a suitable material that provides acceptable cost and durability for the dies is also a problem [12].…”