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The aim of this study is to optimise the stainless steel oxidation behaviours during hot rolling. The high temperature oxidation behaviours of ferritic stainless steels B443NT and B445J1M were studied over the temperature range from 1000 to 1150 °C in a humid atmosphere containing 18% water vapour, as measured by a thermogravimetric analyser (TGA). The results indicate that breakaway oxidation occurs at 1090 °C for the B443NT steel, which is 60 °C lower than that for the B445J1M steel. The occurrence of iron oxide nodules on the steels marks the onset of breakaway oxidation; however, the breakaway oxidation phenomenon of B445J1M is different from that of B443NT due to a compact and continuous Mn-Cr spinel which is formed on the surface of B445J1M. The oxide nodules with regenerated Cr2O3 scale underneath the Fe-Cr spinel display better adhesion without showing pores at the metal-scale interface.

Tissue and biomedical engineering fields are in constant mutation and in searching for innovative processing techniques capable to tailor the material properties. In this work, poly(l-lactic acid) (PLLA) and elastomeric poly(glycerol sebacate) (PGS) were dissolved in the same solvents and electrospun together, in a single needle system. A core-shell structure where the hydrophilic PGS was placed onto the surface of the hydrophobic PLLA fibre was obtained for elastomeric concentrations up to 25wt%. It was found that the PLLA:PGS blends are immiscible and the blends present the melting temperatures of the individual polymers. Moreover, their surface properties were deeply influenced by the presence of the PGS, and a superhydrophilic membrane was obtained, after PGS curing at 120°C for 48h. When the concentration of PGS is up to 25wt%, the blend's Young modulus decreases from ∼35.9±7.1 to 7.5±1.4MPa and a twofold improvement in the sample stretchability was observed, compared with the pristine PLLA electrospun samples. Finally, in vitro hypothalamus A59 nerve cell culture shows that the core-shell electrospun samples enhanced cell adhesion and proliferation, suggesting that these developed materials have great potentials for nerve regeneration and biomedical engineering applications.

The breakaway oxidation behaviour of ferritic stainless steels 430, 443 and 445 has been investigatedat 1150•C in humid air. The oxidation kinetics exhibited significant differences among the three ferriticstainless steels. A uniform and steady growing oxide scale was developed on the 430 steel with an evensteel/oxide interface. Local breakdown of the initially protective oxide scale occurred and oxide noduleswere developed on the 443 and 445 stainless steels, resulting in irregular and rough steel/oxide interfaces. The breakaway oxidation behaviour was significantly influenced by the microstructure and thecomposition of the oxide scale. The Mn-Cr spinel oxide formed on top of the Cr2O3scale in Mo alloying445 steel can greatly minimise the Cr depletion.