About: Laves phase is a(n) research topic. Over the lifetime, 4188 publication(s) have been published within this topic receiving 65316 citation(s).
Papers published on a yearly basis
Abstract: Formation of bulk metallic glass in quaternary Ti–Zr–Cu–Ni alloys by relatively slow cooling from the melt is reported. Thick strips of metallic glass were obtained by the method of metal mold casting. The glass forming ability of the quaternary alloys exceeds that of binary or ternary alloys containing the same elements due to the complexity of the system. The best glass forming alloys such as Ti34Zr11Cu47Ni8 can be cast to at least 4-mm-thick amorphous strips. The critical cooling rate for glass formation is of the order of 250 K/s or less, at least two orders of magnitude lower than that of the best ternary alloys. The glass transition, crystallization, and melting behavior of the alloys were studied by differential scanning calorimetry. The amorphous alloys exhibit a significant undercooled liquid region between the glass transition and first crystallization event. The glass forming ability of these alloys, as determined by the critical cooling rate, exceeds what is expected based on the reduced glass transition temperature. It is also found that the glass forming ability for alloys of similar reduced glass transition temperature can differ by two orders of magnitude as defined by critical cooling rates. The origins of the difference in glass forming ability of the alloys are discussed. It is found that when large composition redistribution accompanies crystallization, glass formation is enhanced. The excellent glass forming ability of alloys such as Ti34Zr11Cu47Ni8 is a result of simultaneously minimizing the nucleation rate of the competing crystalline phases. The ternary/quaternary Laves phase (MgZn2 type) shows the greatest ease of nucleation and plays a key role in determining the optimum compositions for glass formation.
Abstract: CoCrCuFeNiTix (x values in molar ratio, x = 0, 0.5, 0.8 and 1.0) were prepared by arc melting of the pure elements and suction casting under an argon atmosphere. Both CoCrCuFeNi and CoCrCuFeNiTi0.5 alloys form a single FCC solid solution. While the alloys of CoCrCuFeNiTi0.8 and CoCrCuFeNiTi are basically composed of primary FCC solid solution and eutectic mixture of FCC phase and Laves phase of Fe2Ti type. The yield strength of the alloys increases from 230 MPa to 1272 MPa with the increase of Ti addition, among which the CoCrCuFeNiTi0.5 alloy, especially, exhibits compressive strength of up to 1650 MPa together with extensive work hardening and large plastic strain limit of 22%. An interesting transition from paramagnetism to superparamagnetism has been discovered due to the appearance of nanoparticles embedded in the amorphous phase.
Abstract: We propose a new concept of hydrogen absorbing alloy, ‘Laves phase related BCC solid solution’. It was first found among the phases formed in multi-component nominal AB 2 alloys which consisted of Zr and Ti for the A metal site and 5A, 6A and 7A transition metals for the B metal sites. In these alloys a BCC solid solution often coexisted with a Laves phase. It showed stability of hydrides and reaction kinetics almost identical to intermetallics such as Laves phase alloys. We prepared an almost pure ‘Laves phase related BCC solid solution’ and found that it had a large hydrogen capacity (more than 2 mass %) and fast hydrogen absorption and desorption kinetics at ambient temperature and pressure. This new hydrogen absorbing alloy may open a new era of hydrogen related application such as hydrogen vehicles.
01 Jan 1997
Abstract: Advanced microstructure characterisation and microstructure modelling has demonstrated that long-term microstructure stability in 9–12% Cr steels under technical loading conditions is equivalent to precipitate stability. Mo and W can have a positive influence on long-term creep strength of 9–12% Cr steels by Laves phase precipitation hardening. Unexpected breakdown of long-term creep stability of a number of alloys is caused by precipitation of the complex Z-phase nitride, which may completely dissolve fine V and Nb containing MX nitrides. High Cr contents of 10% and above in the steels accelerate Z-phase precipitation.