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In this study, cubic boron nitride (CBN) abrasive segment specimens were produced via high vacuum brazing using Cu–Sn–Ti composite alloys containing tungsten carbide reinforcing particles. The specimen microstructures and interfacial analysis of the brazed CBN grain were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The mechanical properties of hardness, wear resistance, and three-point bending strength of the fabricated specimens were tested. The specimen shape brazed using the composite Cu–Sn–Ti alloy was better than that of the specimen brazed using the pure Cu–Sn–Ti alloy. TiN and TiB2 phases were maintained between the brazed CBN and composite alloys. Meanwhile, TiC compounds were generated between the alloys and WC particles. The hardness of the specimens increased with increasing WC particle content. However, the S25 specimen containing 25 wt% WC particles, exhibited the highest wear resistance and bending strength, increasing by 26.5% and 25.6%, respectively, compared with those of the CBN segment specimen brazed using pure Cu–Sn–Ti alloy. This study provides strategies for developing multilayer brazing CBN abrasive tools.

The ternary (1−x)(0.8BiFeO3-0.2BaTiO3)-xK0.5Na0.5NbO3 (0 ≤ x ≤ 0.5) solid solutions have been successfully synthesized by a solid-state reaction route. X-ray diffraction and Rietveld refinement studies reveal the phase transition from the rhombohedral and tetragonal phases to the single tetragonal phase with x increasing. The average grain size decreases initially and then increases as x increases, whereas the remnant magnetization shows an opposite trend and reaches the maximum value of ~2.09 emu/g at x = 0.3. An enhanced remnant polarization of ~8.6 μC/cm2 appears at x = 0.3 due to the structure distortion and the decrement of defects. Moreover, the remanent polarization and the relative permittivity reach the maximum value of ~20.14 μC/cm2 (10 Hz) and ~644 (1 kHz) at x = 0.5, respectively, and the corresponding dielectric loss decreases to the lowest value of ~0.022 (1 kHz). These results indicate that the properties of ternary BFO-BTO-KNN solid solutions can be modulated by adjusting the K0.5Na0.5NbO3 content to adapt to different application needs.

The polycrystalline Sm and Mn co-substituted bismuth ferrites Bi1-xSmxFe0.95Mn0.05O3 (x = 0.08 and 0.16) with composition near the morphotropic phase boundary have been prepared using a modified solid-state reaction method. The Bi0.92Sm0.08Fe0.95Mn0.05O3 ceramic possesses single rhombohedral phase, whereas the Bi0.84Sm0.16Fe0.95Mn0.05O3 ceramic consists of both the R3c and Pnma phases. The addition of Sm and Mn not only enhances density and grain uniformity but also suppresses the spiral spin modulation which improves the polarization and magnetization. Excellent ferroelectric properties of microdomains are attained in the Bi0.92Sm0.08Fe0.95Mn0.05O3 ceramic. The transition of the nonpolar/antipolar phase to the polar phase and the polarization switching induced by the electric field occur in the Bi0.84Sm0.16Fe0.95Mn0.05O3 ceramic.