TiC Ni Cermet Research Articles

Synthesis of TiC–Ni cermets by the activated reactive evaporation process

This investigation is concerned with the deposition of TiC–Ni cermets using the activated reactive evaporation (ARE) process. A Ti–10 Ni alloy rod was evaporated from an electron beam source in the presence of acetylene (C2H2), the vapor species being activated or partially ionized using the ARE proc microhardness, x-ray fluorescence, x-ray imaging for different elements on an electron microprobe analyzer, optical microscopy, and electron microscopy. It has been shown that TiC–Ni cermets can be deposited by the ARE technique, and they are quite hard. When the deposition was made on Ta substrates at high temperatures, it was observed that Ni diffuses into Ta and forms an intermetallic phase near the interface between the substrate and the deposit.

Synthesis of tic-ni cermets by the activated reactive evaporation process

Synthesis of tic-ni cermets by the activated reactive evaporation process

TiC-Niサーメットの各相の組成について

Each phase of TiC-Ni cermet was studied by means of electrolytic separation and chemical analysis, X-ray diffraction and micro-hardness measurement, with the following results:The solubility of TiC in Ni phase was determined to be 2.7Ti+C, 3.4Ti+C and 5.3Ti+C (in wt%) at 1200°, 1250° and 1300°C, respectively. Although it is considered that Ti dissolves substitutionally in Ni and C dissolves interstitially in it, but the content of C in the solid solution is considerably small as compared with that of Ti. Thus, it is reasonable to consider that free C is present in the phase of the vertical section between Ni and stoichiometric TiC in the Ni-Ti-C system. And it appears that Ni dissolves substitutionally in TiC.The lameller deposit observed in about 90%Ni composition is TiC (a0=4.317 Å). The micro-hardnesses (Hv, 25 g Load) of the Ni and TiC phases were measured to be about 280 kg/mm2 and about 3200 kg/mm2, respectively.

TiC-Niサ一メット押出材の機械的および物理的性質について

TiC-Niサ一メット押出材の機械的および物理的性質について

TiC-Ni系焼結合金の金属結合相の構造と性質

The structures and the properties of binder phase of 70%TiC-30%Ni composition sintered at various temperatures for 1 hr in hydrogen have been investigated by means of X-ray diffraction and thermomagnetic analysis. At about 800°C, titanium carbide begins to diffuse into nickel, the solubility of TiC increased up to 1.5% with rise of the sintering temperature below eutectic temperature and about 1% of TiC remained in binder phase of the alloy sintered above eutectic temperatures. Free carbon content increased gradually during the sintering up to 0.9% by weight, therefore we considered that carbon precipitates during the sintering process of TiC-Ni composition. It was also pointed out that the binder of TiC-Ni cermet must contain excess titanium, and actually, precipitation of graphite in binder phase was observed on the microstructure of TiC-Ni composition sintered above eutectic temperatures. Therefore, in the process of sintering TiC-Ni cermet precipitation of free carbon must be strictly avoided. From this point of view, it has been proposed to add some metal powders, such as molybdenum which combines easily with carbon. It wasfound that molybdenum metal is very suitable for this purpose.

インフィルトレーション法により製造したCr3C2-TiC-Niサーメットについて

This paper describes the testing results of Cr3C2-TiC-Ni cermet prepared by the infiltration method. The cermet was prepared by mixing and compacting carbide powders and subsequently infiltrating with Ni alloy containing 35%Cr3C2 at 1,280°C for 20 min in vacuum. The best of cermets is TiC(10∼20%)-Cr3C2-Ni alloy, which has a 100-hr transverse rupture strength of 89 kg/mm2 at 850°C, and this value exceeds that of TiC-Ni cermet (67 kg/mm2). In respect of oxidation resistance also, this material is very superior.

Studies on TiC-Ni Cermets Sintered in a Hydrogen Molybdenum Furnace

The cermets of TIC-Ni system containing 5 to 30% metallic nickel as a bond were studied. As the technical processes of producing TiC-Co cermets apply almost unmodified to the present case, the authors have limited their attention mainly to the effects of the forming process and the sintering temperature. The compacting pressure, however, was increased to 6ton/cm2 as the higher pressure has proved to give the better results in the sintering shrinkage, and the transverse rupture strength of the sintered psecimens.The general trends which the TiC-Ni system showed in the process of production as well as in the properties of the finished products were found to be the same as in the case of the TiC-Co cermets. Although the former is easier to handle it is less resistive to aerial oxydation than the latter. The study of the micro-photographs of the specimens of TiC-Ni cermets revealed that the grain growth of TiC was accelerated considerably with the increasing Ni content, which is the cause that brings to the lower transverse rupture strength of the finished products.