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Herein, the influence of the impact angle and Ni content on the wear behavior of Mo 2 NiB 2 –Ni cermets was studied using an erodent-carrying slurry comprising artificial seawater and SiO 2 sands. The results reveal that the material loss may be attributed to the wear damage caused by SiO 2 sands because cermets are expected to exhibit good corrosion resistance in artificial seawater. The relative density of cermets markedly influences their resistance to wear damage, and the material loss experienced by cermets with poor relative density is 2–4 times higher than that of cermets with good relative density; this occurs because a higher relative density can markedly enhance the mechanical properties and reduce the defects in the cermets. Moreover, the results indicate that as the impact angle increases from 0° to 60°, the manifestation of the wear mechanism changes from damaging the Ni binder phase (caused by single cutting wear) to damaging both the Mo 2 NiB 2 ceramic and Ni binder phases due to the combination of cutting wear and impact wear. The wear damage is dominated by the cutting wear and impact wear from SiO 2 sand at the low and high impact angles, respectively. Furthermore, the severe deterioration of the single ceramic skeleton at high impact angles indicates that the synergistic influence of the Mo 2 NiB 2 ceramic and Ni binder phases on enhancing the wear resistance of the cermets intensifies at high impact angles. [ABSTRACT FROM AUTHOR]

The effects of normal load and velocity on the friction and wear behavior of single-phase Fe2B bulk have been investigated by optical microscopy, X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. Results indicate that the friction coefficient and wear rate both decrease at first and then increase with increasing load and velocity, respectively. Attributed to the formation of a lamellar film on the Fe2B surface, the lowest friction coefficient and wear rate are obtained at a velocity of 0.2 m/s under a load of 12 N. The dynamic friction coefficients under loads of 4 and 12 N are around 0.8 in the initial steady stage and then decrease to about 0.6, whereas the friction coefficient at 20 N shows no obvious change and remains around 0.82. The lubricating film consisting of Fe2O3, B2O3, SiO2, and H3BO3 reduces the friction coefficient at 0.2 m/s under a load of 12 N. [ABSTRACT FROM AUTHOR]

Effects of chromium addition on microstructure, two-body abrasive wear behavior of Fe–B cast alloy and fracture toughness of boride were investigated. The results indicate the solidification microstructure of Fe–3.0 wt% B alloy consists of ferrite, pearlite and eutectic boride. After quenching, the alloy microstructure is composed of martensite and boride. With Cr addition increasing, microhardness of matrix and boride has tiny fluctuation; fracture toughness of M 2 B increases first reaching the maximum (4.704 MPa m 1/2 ) at 2.0 wt% and then decreases; two-body wear resistance increases first and then decreases under contact loads of 15 N, 35 N and 55 N, possessing similar variation trend with fracture toughness of M 2 B. This indicates the toughness of M 2 B has directly positive influence on wear resistance of Fe–3.0 wt% B cast alloy. [ABSTRACT FROM AUTHOR]

The purpose of this research was to clarify wear-related interactions between the M 2 B phase and the metallic matrix in an Fe-3.0 wt % B duplex alloy, and to characterize those effects on two-body abrasive wear by establishing a mathematical model. Furthermore, the effects of 1.0–2.5 wt % Cr additions on the two-body abrasive wear of the alloy against silica sand paper are discussed in detail. Results of this investigation show that matrix/second phase microstructural interactions significantly decrease the wear of Fe-3.0 wt % B alloy. By comparison, M 2 B plays a predominant role in improving the alloy's wear interaction, while the metallic matrix is detrimental to it. The trend resulting from chromium additions is analogous to the effects of the fracture toughness of M 2 B, and chromium additions also contribute to wear resistance. Improving the fracture toughness of M 2 B not only decreases the wear directly but it also enhances the matrix/second phase wear interactions, which in turn improve the wear resistance of Fe-3.0 wt % B duplex alloy. • For the first time, the metallic matrix/Fe 2 B interaction during abrasive wear is quantitatively characterized. • Wear interaction benefits to decreasing the wear weight loss of Fe-3.0 wt% B duplex alloy. • Improving the fracture toughness of Fe 2 B can enhance the wear interaction. [ABSTRACT FROM AUTHOR]

This research aims to clarify the effects of YAl 2 reinforced particles on the dry sliding wear behaviors of Mg-14 wt%Li-3wt%Al alloy (LA143) against GCr15 steel counterpart. From the obtained results, wear resistance of LA143 can be improved by the addition of YAl 2 as well as the mechanical properties, and the wear rate can be reduced by 10.5–34.4% owing to the reinforcement of YAl 2 particles. With the increase of applied load, the specific wear rate of YAl 2 /LA143 rises while that of LA143 declines gradually. And the coefficients of friction (COFs) for the two materials gradually decrease resulting from the tribological layer on the wear interface. The wear behaviors are mainly dominated by abrasive wear, accompanied by oxidation wear and delamination. YAl 2 particles are beneficial to resisting the damage from GCr15 steel but worsen the COF on the wear surface. • YAl 2 /LA143 composite was fabricated by adding 5 vol% YAl 2 particles into LA143 alloy. • YAl 2 /LA143 shows lower wear rate compared to LA143. • The MML layer plays important role in reducing the friction coefficient. • The specific wear rates show different variation trends with the applied load for LA143 and YAl 2 /LA143. [ABSTRACT FROM AUTHOR]