Structural Analysis of PM Biocomposites Based on Hydroxyapatite Nanopowders Elaborated by Spark Plasma Sintering Route

2012 ◽  
Vol 188 ◽  
pp. 52-58
Author(s):  
Bebe Adrian Olei ◽  
Oana Gîngu ◽  
Nicoleta Lupu ◽  
Gabriela Sima
Keyword(s):  
Structural Analysis ◽  
Spark Plasma Sintering ◽  
High Energy ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Detailed Structural Analysis ◽  
Plasma Sintering ◽  
High Energy Ball Mill ◽  
Spark Plasma ◽  
Energy Ball

The objective of this research is the development of a detailed structural analysis of biocomposites with ceramic matrix of hydroxyapatite (Hap) reinforced by titanium (Ti), elaborated by powder metallurgy technology. Nanometric Hap powders (<200nm) 75% wt and micrometric Ti powders (<150μm) are homogenized in a high energy ball mill Pulverisette 6. Spark plasma sintering (SPS) is the sintering route able to lead to nanostructured sintered samples when nanopowders are used as raw material. The SPS parameters are: the sintering temperature, T=(1000-1100)°C and the maintaining time, t=(10-20) minutes in vacuum. The influence of the sintering parameters on the composites structures is monitored using the optical microscopy (OM), electronic microscopy (SEM) and the X-Ray diffraction (XRD).

Corrosion Behavior and Hardness of Binary Mg Alloys Produced via High Energy Ball-Milling and Subsequent Spark Plasma Sintering

CORROSION ◽  
10.5006/3633 ◽  
2020 ◽  
Author(s):  
Mohammad Umar Farooq Khan ◽  
Taban Larimian ◽  
Tushar Borkar ◽  
Rajeev Gupta
Keyword(s):  
Ball Milling ◽  
Spark Plasma Sintering ◽  
Corrosion Behavior ◽  
High Energy ◽  
High Energy Ball Milling ◽  
X Ray Diffraction ◽  
X Ray ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball

ABSTRACT In this work, nine nanocrystalline binary Mg alloys synthesized by high energy ball milling. The compositions, Mg-5wt.%M (M- Cr, Ge, Mn, Mo, Ta, Ti, V, Y, Zn) were milled with an objective of achieving non-equilibrium alloying. The milled alloys were consolidated via cold compaction (CC) at 25 ï&#x82;°C and spark plasma sintering (SPS) at 300 ï&#x82;°C. X-ray diffraction (XRD) analysis indicated grain refinement below 100 nm, and the scanning electron microscopy revealed homogeneous microstructures for all compositions. X-ray diffraction analysis revealed that most of the alloys showed a change in the lattice parameter, which indicates the formation of a solid solution. A significant increase in the hardness compared to unmilled Mg was observed for all the alloys. The corrosion behavior was improved in all the binary alloys compared to milled Mg. A significant decrease in the cathodic kinetics was evident due to Ge and Zn additions. The influence of the alloying elements on corrosion behavior has been categorized and discussed based on the electrochemical response of their respective binary Mg alloy.

Al-SiC Nanocomposites Produced by Ball Milling and Spark Plasma Sintering

2013 ◽  
Vol 1513 ◽  
Author(s):  
R.C. Picu ◽  
J.J. Gracio ◽  
G.T. Vincze ◽  
N. Mathew ◽  
T. Schubert ◽  
...  
Keyword(s):  
Yield Stress ◽  
Ball Milling ◽  
Spark Plasma Sintering ◽  
High Energy ◽  
Sic Nanoparticles ◽  
Sic Particles ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball ◽  
Annealing Experiments

ABSTRACTIn this work Al-SiC nanocomposites were prepared by high energy ball milling followed by spark plasma sintering of the powder. For this purpose Al micro-powder was mixed with 50 nm diameter SiC nanoparticles. The final composites had grains of approximately 100 nm dimensions, with SiC particles located mostly at grain boundaries. To characterize their mechanical behavior, uniaxial compression, micro- and nano-indentation were performed. Materials with 1vol% SiC as well as nanocrystalline Al produced by the same means with the composite were processed, tested and compared. AA1050 was also considered for reference. It was concluded that the yield stress of the nanocomposite with 1 vol% SiC is 10 times larger than that of regular pure Al (AA1050). Nanocrystalline Al without SiC and processed by the same method has a yield stress 7 times larger than AA1050. Therefore, the largest increase is due to the formation of nanograins, with the SiC particles’ role being primarily that of stabilizing the grains. This was demonstrated by performing annealing experiments at 150°C and 250°C for 2h, in separate experiments.

Nickel/Alumina Metal Matrix Nanocomposites Obtained by High-Energy Ball Milling and Spark Plasma Sintering

2018 ◽  
Author(s):  
Enrique Martínez-Franco ◽  
Ming Li ◽  
Ricardo Cuenca Álvarez ◽  
Jesús González Hernández ◽  
Chao Ma ◽  
...  
Keyword(s):  
Ball Milling ◽  
Spark Plasma Sintering ◽  
Metal Matrix ◽  
High Energy ◽  
Alumina Nanoparticles ◽  
Metal Matrix Nanocomposites ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball ◽  
Matrix Nanocomposites

Metal matrix nanocomposites (MMNCs) are anticipated to offer significantly better performance than existing superalloys. Nickel/alumina nanocomposite samples were fabricated with a powder metallurgy method, combining high-energy ball milling (HEBM) and spark plasma sintering (SPS). The objective of this research is to determine the effect of alumina nanoparticle fraction and HEBM parameters on the powder preparation and sintering processes, and resultant microstructure and properties. Nickel-based powders containing various fractions (1, 5 and 15 vol.%) alumina nanoparticles were prepared by HEBM. The initial particle sizes were 44 μm and 50 nm for nickel and alumina, respectively. The milling process was conducted by starting with mixing at 250 rpm for 5 min, followed by cycling operation at high and low speeds (1200 rpm for 4 min and 150 rpm for 1 min). Samples at different milling times (30, 60, 90 and 120 min) of each composition were obtained. Scanning electron microscopy (SEM) was used to evaluate the dispersion of nanoparticles in the powders at different milling times. SPS technique was used for consolidation of the prepared powders. SEM images showed that alumina nanoparticles are homogeneously dispersed in the metal matrix in the sample containing 15 vol.% alumina. Hardness measurements in cross sections of SPSed samples showed higher values for Ni/Al2O3 MMNC compared to pure Ni.

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.

scholarly journals Refractory High-Entropy HfTaTiNbZr-Based Alloys by Combined Use of Ball Milling and Spark Plasma Sintering: Effect of Milling Intensity

Metals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1268 ◽  
Author(s):  
Natalia Shkodich ◽  
Alexey Sedegov ◽  
Kirill Kuskov ◽  
Sergey Busurin ◽  
Yury Scheck ◽  
...  
Keyword(s):  
Solid Solution ◽  
Ball Milling ◽  
Spark Plasma Sintering ◽  
Vickers Hardness ◽  
High Energy ◽  
High Entropy Alloy ◽  
High Entropy ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Energy Ball

For the first time, a powder of refractory body-centered cubic (bcc) HfTaTiNbZr-based high-entropy alloy (RHEA) was prepared by short-term (90 min) high-energy ball milling (HEBM) followed by spark plasma sintering (SPS) at 1300 °C for 10 min and the resultant bulk material was characterized by XRD and SEM/EDX. The material showed ultra-high Vickers hardness (10.7 GPa) and a density of 9.87 ± 0.18 g/cm³ (98.7%). Our alloy was found to consist of HfZrTiTaNb-based solid solution with bcc structure as a main phase, a hexagonal closest packed (hcp) Hf/Zr-based solid solution, and Me2Fe phases (Me = Hf, Zr) as minor admixtures. Principal elements of the HEA phase were uniformly distributed over the bulk of HfTaTiNbZr-based alloy. Similar alloys synthesized without milling or in the case of low-energy ball milling (LEBM, 10 h) consisted of a bcc HEA and a Hf/Zr-rich hcp solid solution; in this case, the Vickers hardness of such alloys was found to have a value of 6.4 GPa and 5.8 GPa, respectively.

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