59328-60-8

Upstream product

• 7440-32-6 titanium 
• 7440-02-0 nickel 
• 14336-71-1 calcium chloride 

Relevant academic research and scientific papers

PHASE RELATIONS AND DIFFUSION PATHS IN THE Ti-Ni-Fe SYSTEM AT 900 degree C.

A study was made of the 900 degree C cross section through the ternary phase diagram Ti-Ni-Fe by means of the diffusion couple technique and by investigating equilibrated alloys. The course of a number of diffusion paths was established. Use was made of optical, microprobe, and X-ray analyses. Some hitherto unaccountable results mentioned in the literature have been explained.

Production of NiTi via the FFC cambridge process

The FFC Cambridge process is a direct electrodeoxidation process used to reduce metal oxides to their constituent metals in a molten Ca Cl2 salt bath. NiTi O3 was used as a precursor (the first stable oxide to form upon blending and sintering NiO and Ti O2 powders) and was successfully reduced using the FFC Cambridge process at 1173 K and a constant cell voltage of -3.1 V to produce a NiTi alloy. This work builds on the literature work [Chinese Science Bulletin, 51, 2535 (2006)] through: (i) a predominance diagram calculated to show the regions of phase stability throughout the usable potential window of the Ca Cl2 salt; (ii) the investigation of a wide range of reduction times for a fixed cell voltage, elucidating several additional stable phases, to yield a complete and detailed reduction pathway. The reduction pathway for NiTi O3 was identified through the analysis of a series of partial reductions, with fully reduced NiTi formed after a period of 24 h. The first stage of the reaction involved the rapid formation of Ni and CaTi O3. The reduction then proceeded via the formation of the intermediate compounds Ni3 Ti and Ni2 Ti4O. All the NiTi O3 and Ni were consumed after a period of 6 h, while the intermediate compounds remained until the reaction was near completion. The experimental results related well to the thermodynamic predictions of the predominance diagram. A small variation in stoichiometry of the produced NiTi observed from the edge to the core of the samples was attributed to redeposition of Ti on the sample surface from the salt and a slightly Ti-rich NiTi O3 precursor material.

Effect of Ni content on the products of Ni-Ti-B system via self-propagating high-temperature synthesis reaction

The effect of Ni content on the products of Ni-Ti-B system via self-propagating high-temperature synthesis (SHS) reaction has been investigated in this research. The results show that the products of SHS reactions consist mainly of TiB2 and Ni.

Synthesis of NiTi intermetallics by self-propagating combustion

The production of NiTi intermetallic compounds from elemental powder compacts was conducted by self-propagating high-temperature synthesis (SHS) in this study. Effects of initial sample density, preheating temperature, and Ni particle size on the combustion characteristics, as well as on the final composition and morphology of products were studied. For the samples with densities between 50 and 60% theoretical maximum density (TMD) under preheating temperatures in the range of 100-300°C, the synthesis process showed two consecutive combustion stages, including the propagation of combustion front and the subsequent bulk combustion. Under these conditions, high-density products containing NiTi as the major phase with small amounts of secondary phases of NiTi2 and Ni3Ti were obtained. However, porous combustion products with a significant amount of unreacted Ni were produced from the 45% TMD samples under preheating temperatures of 100 and 150°C, due to the lack of the second combustion stage. The amount of unreacted Ni in the final composition was greatly reduced by increasing the initial sample density and preheating temperature, or by using smaller Ni particles in the samples. In addition, the use of smaller Ni particles also led to an increase in the product density up to about 95% relative to the density of NiTi intermetallic.

Combustion synthesis of TiNi intermetallic compounds: Part 2. Effect of TiO2 formation

Equiatomic titanium and nickel compacted powders were synthesized into a TiNi intermetallic compound using a thermal explosion mode of the self-propagating high-temperature synthesis (SHS) method in air. It was found that the combustion temperature (Tsub