In this work, a series of experiments were conducted to evaluate the effect of applied potential on the tribocorrosion behavior of 410SS using a tribometer integrated with an electrochemical workstation. Results show that tribocorrosion rate of 410SS varies with applied potential and reaches a maximum at À0.1 V. By applying potential pulse method, it indicates that the repassivation kinetics of 410SS is much slower than general stainless steels.The XPS results reveal great changes in the composition of tribocorrosion products, which are enriched in Fe 3 O 4 and Fe(OH) 2 in the lower potential range while become Fe 2 O 3 , FeOOH, and Fe(OH) 3 at more positive potential. The characteristics of tribocorrosion products depend on surface chemistry which varies in compliance with applied potential, and thus, alters the tribocorrosion rate of 410SS. Moreover, the synergistic effect between wear and corrosion was quantified, showing that pure mechanical wear and corrosion-induced wear were the main reasons for the degradation of 410SS.

Tribocorrosion is often complicated and harmful to metallic components, which depends on the mechanics of the tribological contact, on the electrochemical characters, on the properties of the contacting materials, and on the physico‐chemical properties of the environment. In this work, effects of corrosive media on the friction and wear behaviour, on the corrosion behaviour and on the synergistic effect between them were investigated in detail on a pin‐on‐disc tribometer. Although no electrochemical corrosion occurs in distilled water, its lubricity is so bad that plastic ratchetting effect and abrasive wear are observed on 304SS surface which result in severe material loss. In other three simulated seawater, corrosion and wear interact positively, making the pure mechanical wear and corrosion accelerated wear including abrasion and delamination, be the main reasons for 304SS degradation. Note that solution pH also plays an important role in determining material degradation.

Orthorhombic CeNiSi2-type polycrystalline RNiSi2 (R=Gd, Dy, Ho, Er, Tm) compounds were synthesized and the magnetic and magnetocaloric properties were investigated in detail. The transition temperatures of RNiSi2 compounds are all in a very low temperature range (<30 K). As temperature increases, all of the compounds undergo an AFM to PM transition (GdNiSi2 at 18 K, DyNiSi2 at 25 K, HoNiSi2 at 10.5 K, ErNiSi2 at 3 K and TmNiSi2 at 3.5 K, respectively). ErNiSi2 compound shows the largest (ΔSM)max (maximal magnetic entropy change) among these compounds. The value of (ΔSM)max is 27.9 J/kgK under a field change of 0-5 T, which indicates that ErNiSi2 compound is very competitive for practical applications in low-temperature magnetic refrigeration in the future. DyNiSi2 compound shows large inverse MCE (almost equals to the normal MCE) below the TN which results from metamagenitic transition under magnetic field. Considering of the normal and inverse MCE, DyNiSi2 compound also has potential applications in low-temperature multistage refrigeration.

The microstructure and phase chemistry of melt-spun nanocomposite Pr9.7Fe76.6Co7.8B5.9 and Pr9.2Fe69.4Co15.4B6.0 ribbons have been studied using three-dimensional atom probe (3DAP) and transmission electron microscopy. The microstructure of these alloys consists of two phases, bcc α-Fe–Co and tetragonal Pr2(FeCo)14B. Practically all of the B and Pr atoms are rejected from the α-Fe–Co phase and are concentrated into the 2/14/1 hard magnetic phase. However, no significant difference of Co concentration between the two phases is observed. From the measured Co concentration in the 2/14/1 phase, it is explained why the effect of Co content on Curie temperature (Tc) is greater in the nanocomposite alloys than in single phase alloys. Predictions of Tc for the nanocomposite alloys based on the 3DAP composition data show excellent agreement with experimental measurements.

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The hard magnetic (La,Ce)Co5 nanoflakes with high coercivity and narrow thickness distribution have been successfully obtained by surfactant-assisted ball milling (SABM). The magnetic properties, morphology and interaction of (La,Ce)Co5 nanoflakes are studied in this work. The coercivity and remanence ratio of (La,Ce)Co5 nanoflakes are 5.48 kOe and 0.71, respectively. The X-ray powder diffraction (XRD) patterns indicate that the (La,Ce)Co5 nanoflakes are CaCu5-type hexagonal crystal structure. The average thickness and aspect ratio are 47 nm and 40, respectively. The intergrain interaction of the (La,Ce)Co5 nanoflakes is studied using the δm(H)-curves technique which shows the magnetostatic-dominated particle interaction. The high coercivity and narrow thickness distribution of (La,Ce)Co5 nanoflakes could be promising for the future development of the high performance soft/hard exchange spring magnets.