scholarly journals Synthesis of Intermetallics in Fe-Al-Si System by Mechanical Alloying

Metals ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 20 ◽  
Author(s):  
Kateřina Nová ◽  
Pavel Novák ◽  
Filip Průša ◽  
Jaromír Kopeček ◽  
Jaroslav Čech
Keyword(s):  
Mechanical Alloying ◽  
High Energy ◽  
Sintering Behavior ◽  
Mechanically Alloyed ◽  
Silicon Alloys ◽  
High Temperature Mechanical Properties ◽  
Plasma Sintering ◽  
Initial Stage ◽  
Feal Phase ◽  
Spark Plasma

Fe-Al-Si alloys have been recently developed in order to obtain excellent high-temperature mechanical properties and oxidation resistance. However, their production by conventional metallurgical processes is problematic. In this work, an innovative processing method, based on ultra-high energy mechanical alloying, has been tested for the preparation of these alloys. It has been found that the powders of low-silicon alloys (up to 10 wt. %) consist of FeAl phase supersaturated by Si after mechanical alloying. Fe2Al5 phase forms as a transient phase at the initial stage of mechanical alloying. The alloy containing 20 wt. % of Si and 20 wt. % of Al is composed mostly of iron silicides (Fe3Si and FeSi) and FeAl ordered phase. Thermal stability of the mechanically alloyed powders was studied in order to predict the sintering behavior during possible compaction via spark plasma sintering or other methods. The formation of Fe2Al5 phase and Fe3Si or Fe2Al3Si3 phases was detected after annealing depending on the alloy composition. It implies that the powders after mechanical alloying are in a metastable state; therefore, chemical reactions can be expected in the powders during sintering.

Effect of Aluminum on Fabrication of Ti3SiC2 by Mechanical Alloying and Spark Plasma Sintering

2007 ◽  
Vol 336-338 ◽  
pp. 1065-1068
Author(s):  
Song Zhe Jin ◽  
Bao Yan Liang ◽  
Jing Feng Li ◽  
Li Li
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
High Purity ◽  
Trace Amount ◽  
High Energy ◽  
Alloyed Powder ◽  
Mechanically Alloyed ◽  
Starting Mixture ◽  
Plasma Sintering ◽  
Spark Plasma

In the present study, we fabricated high purity and electrically machinable Ti3SiC2 ceramics by mechanical alloying and subsequent spark plasma sintering. The effect of a trace amount of Al on these synthesis processes was examined. Our results showed that Ti3SiC2 could be synthesized by high energy milling. Spark plasma sintering of mechanically alloyed powder at the temperatures of 1000-1200°C produced nearly single-phased Ti3SiC2 materials. The purity of the sintered Ti3SiC2 bulk was remarkably increased by addition of a small amount of Al. Ti3SiC2 with a purity of 99.3 wt% and a relative density of 98.9% was obtained by mechanical alloying and subsequent spark plasma sintering from a starting mixture composed of n(Ti) : n(Si) : n(Al) : n(c) = 3 : 1 : 0.2 : 2 at 1100°C.

scholarly journals Mechanical and Tribological Behavior of Mechanically Alloyed Ni-TiC Composites Processed via Spark Plasma Sintering

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5306
Author(s):  
Ganesh Walunj ◽  
Anthony Bearden ◽  
Amit Patil ◽  
Taban Larimian ◽  
Jijo Christudasjustus ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
High Energy ◽  
Matrix Composites ◽  
Nickel Matrix ◽  
Mechanically Alloyed ◽  
Plasma Sintering ◽  
High Energy Ball Mill ◽  
Spark Plasma ◽  
Equilibrium Process

Titanium carbide (TiC) reinforced nickel (Ni) matrix composites were processed via mechanical alloying (MA) followed by spark plasma sintering (SPS) process. Mechanical alloying has gained special attention as a powerful non-equilibrium process for fabricating amorphous and nanocrystalline materials, whereas spark plasma sintering (SPS) is a unique technique for processing dense and near net shape bulk alloys with homogenous microstructure. TiC reinforcement varied from 5 to 50 wt.% into nickel matrix to investigate its effect on the microstructure and mechanical behavior of Ni-TiC composites. All Ni-TiC composites powder was mechanically alloyed using planetary high energy ball mill with 400 rpm and ball to powder ratio (BPR) 15:1 for 24 h. Bulk Ni-TiC composites were then sintered via SPS process at 50 MPa pressure and 900–1200 °C temperature. All Ni-TiC composites exhibited higher microhardness and compressive strength than pure nickel due to the presence of homogeneously distributed TiC particles within the nickel matrix, matrix grain refinement, and excellent interfacial bonding between nickel and TiC reinforcement. There is an increase in Ni-TiC composites microhardness with an increase in TiC reinforcement from 5 to 50 wt.%, and it reaches the maximum value of 900 HV for Ni-50TiC composites.

scholarly journals Structure and Deformation Behavior of Ti-SiC Composites Made by Mechanical Alloying and Spark Plasma Sintering

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1276 ◽  
Author(s):  
Dariusz Garbiec ◽  
Volf Leshchynsky ◽  
Alberto Colella ◽  
Paolo Matteazzi ◽  
Piotr Siwak
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
Indentation Size Effect ◽  
Sintering Temperature ◽  
High Energy ◽  
Indentation Size ◽  
X Ray ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball

Combining high energy ball milling and spark plasma sintering is one of the most promising technologies in materials science. The mechanical alloying process enables the production of nanostructured composite powders that can be successfully spark plasma sintered in a very short time, while preserving the nanostructure and enhancing the mechanical properties of the composite. Composites with MAX phases are among the most promising materials. In this study, Ti/SiC composite powder was produced by high energy ball milling and then consolidated by spark plasma sintering. During both processes, Ti3SiC2, TiC and Ti5Si3 phases were formed. Scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction study showed that the phase composition of the spark plasma sintered composites consists mainly of Ti3SiC2 and a mixture of TiC and Ti5Si3 phases which have a different indentation size effect. The influence of the sintering temperature on the Ti-SiC composite structure and properties is defined. The effect of the Ti3SiC2 MAX phase grain growth was found at a sintering temperature of 1400–1450 °C. The indentation size effect at the nanoscale for Ti3SiC2, TiC+Ti5Si3 and SiC-Ti phases is analyzed on the basis of the strain gradient plasticity theory and the equation constants were defined.

Nanoindentation Characterization of Mechanically Alloyed Fe-Al-Si Powders

2018 ◽  
Vol 784 ◽  
pp. 15-20 ◽  
Author(s):  
Petr Haušild ◽  
Jaroslav Čech ◽  
Miroslav Karlík ◽  
Filip Průša ◽  
Pavel Novák ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Preparation Technique ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Microstructure And Mechanical Properties ◽  
Plasma Sintering ◽  
Special Sample Preparation ◽  
Spark Plasma ◽  
Powder Particles

The effect of processing conditions on microstructure and mechanical properties of Fe-Al-Si powders was studied by means of scanning electron microscopy, X-ray diffraction and nanoindentation. Fe-Al-Si alloy powder was prepared from pure elemental powders by mechanical alloying. Microstructure and mechanical properties of powders were characterized after various durations of mechanical alloying. Special sample preparation technique was developed allowing to characterize the properties of individual powder particles after each step of processing in a planetary ball mill. This step-by-step characterization allowed to find the optimum conditions for subsequent spark plasma sintering.

Thermoelectric Performance of Nanostructured ZrNiSn Compounds Synthesized by Mechanical Alloying

2010 ◽  
Vol 1267 ◽  
Author(s):  
Jeffrey D Germond ◽  
Paul J Schilling ◽  
Nathan J. Takas ◽  
Pierre F. P. Poudeu
Keyword(s):  
Thermal Conductivity ◽  
Mechanical Alloying ◽  
Phonon Scattering ◽  
High Energy ◽  
Inert Atmosphere ◽  
Base System ◽  
Plasma Sintering ◽  
High Energy Ball Mill ◽  
Spark Plasma ◽  
Diffraction Patterns

AbstractSamples with a composition ZrNiSn were synthesized by a combination of mechanical alloying (MA) and consolidation by either Spark Plasma Sintering (SPS) or hot pressing (HP). Appropriate stoichiometric ratios of the starting materials were milled under an inert atmosphere in a high energy ball mill for 6 hours, achieving a half-Heusler phase. X-Ray diffraction patterns of as milled powders and consolidated samples were compared and analyzed for phase purity. Thermal conductivity, electrical conductivity and Seebeck coefficient were measured as a function of temperature in the range 300 K to 800 K and compared with measurements reported for high temperature solid state reaction synthesis of this compound. HP samples, compared to SPS samples, demonstrate increased grain growth due to longer heating times. Reduced grain size achieved by MA and SPS causes increased phonon scattering due to the increased number of grain boundaries, which lowers the thermal conductivity without doping the base system with addition phonon scattering centers.

Synthesis of Fullerene by Spark Plasma Sintering and Thermomechanical Transformation of Fullerene Into Diamond on Fe-C Composites

2009 ◽  
Vol 1243 ◽  
Author(s):  
Francisco C. Robles-Hernández ◽  
H. A. Calderon
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
Thermomechanical Processing ◽  
Control Agent ◽  
Mechanically Alloyed ◽  
Characterization Methods ◽  
Nanostructured Composite ◽  
Heating And Cooling ◽  
Plasma Sintering ◽  
Spark Plasma

ABSTRACTIn this work, results are presented regarding the characterization of nanostructured Fe matrix composites reinforced with fullerene. The fullerene is a mix of 15 wt.%C60, 5 wt.%C70 and 80 wt.% soot that is the product of the primary synthesis of C60. The composite has been produced by means of mechanical alloying and sintered by Spark Plasma Sintering (SPS). The characterization methods include XRD, SEM and TEM. The C60 and C70 withstand mechanical alloying, SPS, and thermomechanical processing and act as a control agent during mechanical alloying. The results show that the mechanically alloyed and SPS product is a nanostructured composite. A larger amount of C60 is found in the sintered composite than in the original fullerene mix, which is attributed to an in-situ synthesis of C60 during the SPS process. The synthesis of C60 is presumably assisted by the catalytic nature of Fe and the electric field generated during the SPS process. In order to study the effect of high temperature, high strain, high heating and cooling rates on C60, the composite is subjected to a thermomechanical processing; demonstrating that some of the C60 resists the above described environment and some of it partially transforms into diamond.

Production of Cu-Hf-Ti Bulk Glassy Composites by Mechanical Alloying and Spark-Plasma Sintering

2006 ◽  
Vol 118 ◽  
pp. 655-660 ◽  
Author(s):  
Pyuck Pa Choi ◽  
Ji Soon Kim ◽  
Hyeong Suk Choi ◽  
Dae Hwan Kwon ◽  
Young Soon Kwon
Keyword(s):  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
High Energy ◽  
Amorphous Structure ◽  
Liquid Region ◽  
Scanning Calorimetry ◽  
Plasma Sintering ◽  
Stage Crystallization ◽  
Spark Plasma ◽  
Dsc Analyses

This work reports on the production of Cu-Hf-Ti bulk glassy composites through a powder metallurgical route, i.e. by mechanical alloying and subsequent spark-plasma sintering. Powders of Cu60Hf30Cu10 and Cu60Hf25Ti15 composition were prepared using a high-energy planetary ball-mill. Both alloys nearly showed a fully amorphous structure with only a small fraction of residual HCP Hf grains left after 50 h of milling. Differential scanning calorimetry (DSC) analyses of the milled glassy powder revealed a two-stage crystallization process for both compositions. However, the released crystallization enthalpy was substantially larger for the Cu60Hf25Ti15 alloy than for the Cu60Hf30Ti10 alloy, suggesting that the former comprises a higher fraction of the amorphous phase than the latter. Both powders showed distinct glass-transition with a large super-cooled liquid region. Consolidation of Cu60Hf25Ti15 powder was carried out by means of spark-plasma sintering at applied pressures of 200 and 500 MPa, choosing a sintering temperature within the super-cooled liquid region (T = 753 K). The sintered compacts exhibited some pores and interparticle boundaries.

scholarly journals Effect of Initial Powders on Properties of FeAlSi Intermetallics

Materials ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 2846 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Václav Bouček ◽  
Kateřina Nová ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Phase Composition ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Sintering Process ◽  
High Temperature Mechanical Properties ◽  
Plasma Sintering ◽  
Indentation Tests ◽  
Spark Plasma ◽  
Metallurgical Processes

FeAlSi intermetallics are materials with promising high-temperature mechanical properties and oxidation resistance. Nevertheless, their production by standard metallurgical processes is complicated. In this study, preparation of powders by mechanical alloying and properties of the samples compacted by spark plasma sintering was studied. Various initial feedstock materials were mixed to prepare the material with the same chemical composition. Time of mechanical alloying leading to complete homogenization of powders was estimated based on the microstructure observations, results of XRD and indentation tests. Microstructure, phase composition, hardness and fracture toughness of sintered samples was studied and compared with the properties of powders before the sintering process. It was found that independently of initial feedstock powder, the resulting phase composition was the same (Fe3Si + FeSi). The combination of hard initial powders required the longest milling time, but it led to the highest values of fracture toughness.

Ti50Fe22Ni22Sn6 Amorphous Alloy Synthesized by Mechanical Alloying and Spark Plasma Sintering

2011 ◽  
Vol 393-395 ◽  
pp. 485-488 ◽  
Author(s):  
Qiang Li ◽  
Yu Ying Zhu ◽  
Ge Wang
Keyword(s):  
Glass Transition ◽  
Amorphous Alloy ◽  
Mechanical Alloying ◽  
Spark Plasma Sintering ◽  
Crystallization Temperature ◽  
Amorphous Powder ◽  
High Energy ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Initial Crystallization Temperature

Ti50Fe22Ni22Sn6 amorphous alloy is prepared by mechanical alloying and spark plasma sintering. The milling is performed in a high-energy planetary ball mill. XRD shows that after milled 70h, fully amorphous powders can be obtained, under the condition of the milling speed, 300rpm, and the weighs ratio of ball to powder, 10:1. Thermal stability of the as-milled amorphous powder is determined by DSC at the heating rate of 40K/min. The glass transition Tg and the initial crystallization temperature Tx1 is 625K and 770K, respectively. The amorphous alloy powder is compacted by spark plasma sintering at the temperature of 633K, 653K, 673K, 688K and 723K under the compress of 400Mpa. From XRD, it can be seen that near the glass transition temperature, the samples sintered remain completely amorphous, and when the sintering temperature increasing, although not higher than the initial crystallization temperature, the sintered samples have begun to appear crystalline phases.

Sign in / Sign up

Export Citation Format

Share Document