Kinetics of mechanically activated high temperature synthesis of Ni3Al in the thermal explosion mode

High-temperature synthesis of nickel-zinc ferrite Ni0.75Zn0.25Fe2O4 has been carried out under heating in high temperature chamber and by radiation-thermal treatment under influence of intensive electron beam. It is shown that after irradiation in the temperature range 600-1000ºC there is a significant increase in the reaction rate and product shrinkage, ceramics grain size uniformity also increases

Download Full-text

Oxidation Behavior of TiC/ Fe Ceramics Produced by Self-Propagating High-Temperature Synthesis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.434-435.116 ◽

2010 ◽

Vol 434-435 ◽

pp. 116-119 ◽

Cited By ~ 1

Author(s):

Bin Li ◽

Zong De Liu ◽

Li Ping Zhao ◽

Yan Rong Bao

Keyword(s):

High Temperature ◽

Synthesis Method ◽

Isothermal Oxidation ◽

Composite Ceramics ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Oxidation Properties ◽

Kinetics Of ◽

Static Pressing

The key problem about the application of TiC/Fe composite ceramics in high temperature is the oxidation resistance. With an aim to investigate oxidation properties, the high density TiC/Fe ceramics was produced by self-propagating high-temperature synthesis method combined with pseudo hot iso-static pressing (SHS/PHIP). The oxidation kinetics of TiC/Fe ceramics were investigated by means of conducting the isothermal oxidation experiments in air at temperature of 550°C  900°C for up to 150 hours, and measuring the variations of the weight gains of the composites with the oxidation times. The microstructure evolution of the composites during the oxidation processing was studied by using SEM/EDS and XRD. Experimental results show that TiC/Fe ceramics basically follows a parabolic rule at high temperature. A detailed characterization of the microstructure and distribution of the phases within the scale following oxidation studies has been undertaken to suggest the possible mechanism for the oxidation of TiC/Fe ceramics.

Download Full-text

Synchrotron in situ studies of mechanical activation treatment and γ-radiation impact on structural-phase transitions and high-temperature synthesis parameters during the formation of γ-(TiAl) compound

Journal of Synchrotron Radiation ◽

10.1107/s1600577519010014 ◽

2019 ◽

Vol 26 (5) ◽

pp. 1671-1678 ◽

Cited By ~ 1

Author(s):

Marina Loginova ◽

Alexey Sobachkin ◽

Alexander Sitnikov ◽

Vladimir Yakovlev ◽

Valeriy Filimonov ◽

...

Keyword(s):

High Temperature ◽

Mechanical Activation ◽

Thermal Explosion ◽

Powder Mixture ◽

Maximum Temperature ◽

Γ Irradiation ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

The Impact

In situ synchrotron studies of structure and phase formation dynamics in mechanically activated (t = 7 min, power density 40 g) and mechanically activated with subsequent irradiation by γ-quanta 60Co powder mixture (Ti 64 wt% + Al) during high-temperature synthesis by the method of thermal explosion using induction heating are described. In situ high-temperature synthesis was carried out on the created experimental complex adapted for synchrotron X-ray diffraction methods. The sequence of formation and time–temperature interval of the metastable and main phases were determined. The impact of preliminary mechanical activation and of γ-irradiation on the macrokinetic parameters of the synthesis were studied experimentally in situ. It has been established that the impact of γ-irradiation on the mechanically activated powder mixture of the composition Ti 64 wt% + Al leads to a change in the thermal parameters of combustion: the maximum synthesis temperature and the burning rate decrease. The heating rate for the non-irradiated mixture is 204.8 K s−1 and that for the irradiated mixture is 81.6 K s−1. The dependences of mass fractions of the synthesized compounds on time and temperature were calculated from the stage of preheating until completion of the thermal explosion. A single-phase equilibrium product of the composition γ-(TiAl) is formed in γ-irradiated mechanically activated mixture when the system reaches maximum temperature. The synthesized product of the mechanically activated mixture without γ-irradiation contains 72% γ-(TiAl); TiAl3 (26%) and residual Ti (2%) are also observed.

Download Full-text

The Obtaining of the Intermetallic Compounds of Ni-Al System by Self-Propagating High Temperature Synthesis and Thermal Explosion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1114.135 ◽

2015 ◽

Vol 1114 ◽

pp. 135-142

Author(s):

Mihai Cojocaru ◽

Florică Tudose

Keyword(s):

High Temperature ◽

Intermetallic Compounds ◽

Thermal Explosion ◽

Melting Temperature ◽

Aerospace Industry ◽

Point Of View ◽

Temperature Synthesis ◽

Practical Point ◽

High Temperature Synthesis

The intermetallic compounds (IMC) of Ni-Al system exhibit interest both by theoretical and practical point of view: theoretically, due to particular aspects in relation to their synthesis and practically, due to their qualities that recommend them for the top industries such as, for example, the aerospace industry. In this paper are shown the results of researches on obtaining of high temperature compounds of Ni-Al system by self-propagating high temperature synthesis and thermal explosion, through the initiation of process at a temperature below the melting temperature of the easy fusible component.

Download Full-text