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The effect of 2–8 mol.% Mo and 4 mol.% C additions on magnetic properties of TiC–10TiN–30Ni (mol.%) cermet was investigated. Saturation magnetization M s , remanence M r and Curie temperature T c of as-sintered cermets (1420 °C, 1 h) decreased with increasing Mo. This was mainly attributed to that the total content of non-magnetic alloying elements Mo and Ti in Ni-based binder phase increased with increasing Mo in cermets, leading to the weakening of magnetic exchange interaction among Ni atoms in binder phase. The further addition of 4 mol.% C inversely increased M s , M r and T c of cermets, which was mainly attributed to that it decreased the total content of Mo and Ti in binder phase, leading to the strengthening of magnetic exchange interaction among Ni atoms in binder phase. T c of cermets without C addition was about 250 K at 6 mol.% Mo and 115 K at 8 mol.% Mo, respectively, and that of cermets with 4 mol.% C addition was about 194 K at 8 mol.% Mo. [ABSTRACT FROM AUTHOR]

(Ti 1-x W x )C solid solutions (x = 0.05, 0.15, 0.25, 0.35) were synthesized by carbothermal reduction and then were used as hard phases to prepare (Ti,W)C-Ni 3 Al cermets by vacuum sintering. (Ti,W)C-Ni 3 Al cermets showed weak core-rim structure carbide particles embedded in Ni 3 Al binder. As W content in (Ti,W)C increased, core-rim structure of carbide particles got weaker and the contrast of particles lowered down in SEM-BSE morphologies. Furthermore, the densification of cermets was promoted with W content in solid solution increasing, meanwhile TRS and toughness of cermets were improved obviously. In this paper, the wettability of molten metal on different group transition metal carbides was discussed in detail based on valence-electron configurations (VECs) of carbides. [ABSTRACT FROM AUTHOR]

Abstract The present work investigated magnetic and mechanical properties of TiC– x TiN–15MC– y Ni (wt.%, MC = Mo 2 C, WC, x = 0, 3, 6, 9, 12, 15, and y = 20, 40) cermets. Room-temperature (RT) saturation magnetization M s of Mo 2 C-containing and WC-containing cermets decreased with increasing x , and that of Mo 2 C-containing cermets was lower at the same x and y. Ferromagnetism disappeared at RT for Mo 2 C-containing cermets regardless of x and y and for WC-containing cermets at x = 15 for y = 20 and x ≥ 12 for y = 40, mainly due to high total content of non-magnetic Mo (or W) and Ti in binder phase. At x = 15, Curie temperature T c of Mo 2 C-containing cermets decreased to about 97 K for y = 20 and 16 K for y = 40. For Mo 2 C-containing cermets, transverse rupture strength (TRS) and hardness reached the maximum at x = 6 for y = 20, and they increased with increasing x for y = 40. For WC-containing cermets, TRS reached the maximum at x = 6 whereas hardness decreased slowly with increasing x for y = 20, and TRS and hardness reached the maximum at x = 12 and 6 for y = 40, respectively. TRS and hardness of Mo 2 C-containing cermets were higher than those of WC-containing cermets at the same x and y , except x = 0, 15 for y = 20, mainly due to stronger ceramic grain refinement strengthening effect and stronger substitutional solid-solution strengthening effect of binder phase. Highlights • RT M s of cermets decreased with increasing TiN content, regardless of MC. • Ferromagnetism of cermets disappeared at RT for MC = Mo 2 C, regardless of x and y. • Ferromagnetism of cermets disappeared at RT for MC = WC at x = 15 for y = 20, 40. • For MC = Mo 2 C, T c of cermets decreased to ∼97 K for y = 20 and ∼16 K for y = 40. • TRS and hardness of cermets were generally higher for MC = Mo 2 C than for MC = WC. [ABSTRACT FROM AUTHOR]

Microstructure and shear strength of Ti(C,N)-based cermet/Cu 30Ag 3Ti filler metal/W9Mo3Cr4V steel joints were investigated after brazing in vacuum at 870, 910, and 950 °C for 20 min, and 910 °C for 10, 20, 30 and 40 min. The reaction layer of Cu Ni Ti solid solution between cermet and filler metal was difficult to form during brazing at 870 °C, leading to very low shear strength of joints. During brazing at 910 °C, Cu Ni Ti solid solution was formed between cermet and filler metal, and it became thick with the increase of holding time. Shear strength of joints reached a peak value for 30 min, due to the appropriate thickness of Cu Ni Ti solid solution. During brazing at 950 °C, Cu Ni Ti solid solution was formed and then grew on the whole along with Ag-based solid solution in filler metal, but was not formed between cermet and filler metal, thus deteriorating shear strength of joints. [ABSTRACT FROM AUTHOR]