How to overcome the main challenges of SPS technology: Reproducibility, multi-samples and elaboration of complex shapes

The spark plasma sintering process (SPS) permits the densification of a wide variety of materials [1–2] (metals, alloys, ceramic, polymer, and composites). This breakthrough sintering technique is able to create highly dense materials with micro-structural control and a very short processing time [3–5]. Although it has experienced a very strong growth in the last three decades in terms of publications and patents, its industrialization is still in its infancy. This is mainly due to the fact that only pieces of simple geometries have been densified so far, and that this technology is considered to suffer from a lack of reproducibility and productivity. We will try to show in this chapter how to overcome three of the main challenges of SPS technology: reproducibility, multi-samples, and elaboration of complex shapes

Review of thermo-physical properties, wetting and heat transfer characteristics of nanofluids and their applicability in industrial quench heat treatment

The success of quenching process during industrial heat treatment mainly depends on the heat transfer characteristics of the quenching medium. In the case of quenching, the scope for redesigning the system or operational parameters for enhancing the heat transfer is very much limited and the emphasis should be on designing quench media with enhanced heat transfer characteristics. Recent studies on nanofluids have shown that these fluids offer improved wetting and heat transfer characteristics. Further water-based nanofluids are environment friendly as compared to mineral oil quench media. These potential advantages have led to the development of nanofluid-based quench media for heat treatment practices. In this article, thermo-physical properties, wetting and boiling heat transfer characteristics of nanofluids are reviewed and discussed. The unique thermal and heat transfer characteristics of nanofluids would be extremely useful for exploiting them as quench media for industrial heat treatment