Volume 44, Issue 11,
1 August 2018
, Pages 13176-13181
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In this study, mullite ceramic matrix composites (CMCs) reinforced with Ta2O5 particles (10 wt%) were fabricated through spark plasma sintering (SPS) and microwave sintering (MW) methods. The prepared batches were sintered at 1200 °C and 1300 °C in SPS method. The composite was also sintered at 1300 °C by MW method. In SPS, in order to achieve maximum densities, the sintering temperature increased so that the maximum displacements maintain in each sample. By reaching the temperature to 1200 °C in SPSed sample, the punch displacement stopped, while at 1300 °C in the same sample, it occurred at 1300 °C. The results showed that a high enough density was achieved in SPS sintered samples, while the MW sintered sample revealed higher amounts of porosities (23.81 ± 0.08%) and water absorption (12.20 ± 0.08%) together with low bulk density (2.562 ± 0.003 g/cm3). The values of apparent density, porosity, and water absorption of the SPS sintered sample at 1200 °C were obtained as 3.283 ± 0.002 g/cm3, 2.38 ± 0.05% and 1.02 ± 0.04%. Also, these values for the SPSed sample at 1300 °C were 3.301 ± 0.001 g/cm3, 1.53 ± 0.03% and 0.48 ± 0.05%, respectively. The higher punch displacement, higher bulk density, lower porosity and water absorption of the SPSed sample at 1300 °C might be due to the higher sintering temperature, which causes the reduction of porosities alongside the increase in the probable reactions between the mullite and Ta2O5 phases. The XRD and FESEM investigations revealed the formation of AlTaO4 phases at mullite/Ta2O5 boundaries. It was also proved that increasing the sintering temperature has a significant effect on AlTaO4 phase formation. The SPSed sample at 1200 °C obtained the maximum bending strength of 329 ± 31 MPa in comparison to the sample sintered at 1300 °C (228 ± 26 MPa).
Mullite is one of the most famous aluminosilicate phases in the silica-alumina binary system . During the last decades, many researchers have paid much attention to mullite based composites due to their unique properties, such as high-temperature stability , thermal shock resistance , suitable mechanical strength, , low thermal conductivity, high creep resistance and high chemical stability, which make mullite based composites a suitable option for use in high-temperature applications. Different sintering methods have been carried out to achieve a high relative density in mullite bodies such as conventional sintering, hot pressing , microwave sintering  and spark plasma sintering (SPS). Recent studies have shown that sintering of mullite and mullite based composites via conventional pressureless methods require high temperature and time, which is not economical . Moreover, in this situation, several problems like abnormal grain growth could take place, which reduces mechanical properties such as fracture toughness, fracture strength and so on . Therefore, the use of faster sintering techniques at lower temperatures like pressure-assisted sintering, microwave sintering and SPS have been considered to avoid these problems, . SPS is one of the newest and also fastest sintering techniques to achieve high-density bodies at lower temperatures, especially for materials that cannot be completely sintered thorough conventional sintering methods , , . In this method, the primary powder is sintered by Joule heating and plasma formation, which is caused by the sparks between particles under electrical field , , .
Many types of researches have been done to improve the mechanical properties of mullite bodies. One of the most effective methods is making composites using ceramic or metal reinforcement particles , . These reinforcement particles act as barriers against the growth of cracks  and in some cases, against grain growth during the sintering process, which increase the fracture toughness and strength.
Recent studies have shown that mullite based composites with ceramic reinforcement particles such as tungsten carbide , silicon carbide , zirconia  and titanium carbide  sintered by SPS method exhibit suitable fracture toughness and strength. Rajaei et al.  investigated the effect of tungsten carbide reinforcement particles on mechanical properties of mullite based composites sintered by SPS method. They showed that the fracture strength of a mullite composite containing 10 wt% tungsten carbide is about 80 MPa greater than the monolithic mullite. The effect of silicon carbide whiskers on mechanical properties of mullite based composites sintered by SPS method was investigated by Huang et al. . They showed that upon increasing the silicon carbide whisker volume content, the bending strength of mullite/SiC whisker composite increased significantly. In another study, the effects of zirconia and silicon carbide reinforcement particles on mechanical properties of SPSed mullite based composites were investigated by Gao et al. . Results showed that the bending strength of the composites improved significantly by the addition of ZrO2 and SiC particles. The effect of TiC reinforcement particles on the strength of mullite/TiC composites sintered by SPS method was investigated by Ghahremani et al. . The strength of the mullite-10 vol% TiC composite was proved to reach its maximum value.
However, less information is available on the effects of the addition of oxides on the microstructure and mechanical properties of mullite bodies sintered by SPS and MW sintering methods. As a part of a systematic research, the effect of sintering temperature on the properties of mullite/Ta2O5 composites prepared by SPS and MW sintering methods and also, the reactions involved in such a mullite/oxide particles system have been studied. The study includes the investigation of the effect of two different sintering processes on phase formation, microstructure and mechanical properties of mullite based composites reinforced by Ta2O5 particles.
Nano-sized mullite powders were prepared by a sol-gel method as reported byRajaei et al. . 10 wt% of Ta2O5 powder (Sigma Aldrich-204536, < 20 µm, 99.99%) was added to the synthesized mullite, and the powder mixture was ball-milled in ethanol medium in a polymeric jar using zirconia grinding balls for 5 h at 200 rpm. The ball to powder mass ratio was 5:1. After mixing, the slurry was dried at 60 °C using a magnetic stirrer. The dried mixed powder was put into a graphite die with an inner
Results and discussion
The time-temperature-punch displacement curves of the SPSed samples are shown in Fig. 1(a), (b). Four regions in these curves are detectable. In the first region, by raising the temperature up to 550 °C, no change was detected in the displacements of both samples and so, the heat was just consumed to warm up the powder and the graphite die. In the second region, the initial displacement occurred at a temperature range of 550–600 °C, which is due to an increase in the uniaxial punching pressure
In SPS method, the sample sintered at 1300 °C showed a greater amount of shrinkage and punch displacement during the sintering process. It can be suggested that the greater punch displacement of the SPSed sample at 1300 °C might be due to the higher sintering temperature which causes the reduction of the porosities and might increase the probable reactions between the mullite matrix and reinforcing Ta2O5 phases. The SPS sintered samples exhibited higher bulk densities and lower porosity
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Microstructure and phase formation of mullite-Pr<inf>6</inf>O<inf>11</inf> composite prepared by spark plasma sintering
2023, Journal of Rare Earths
The present work investigates the effect of high praseodymium oxide (Pr6O11) content on the microstructure and phase formation of mullite (3Al2O3·2SiO2) precursor by means of the spark plasma sintering process. 30wt% Pr6O11 was added to a mullite precursor consisting of aluminum nitrate nonahydrate and tetraethyl orthosilicate through a high energy mixer mill in ethanol media. The spark plasma sintering was performed at a temperature of 1200°C under 23Pa vacuum conditions by applying initial and final pressure of 10 and 30MPa, respectively. XRD analysis confirms the existence of mullite, alumina, Pr6O11, Pr2O3 and quartz as the only crystalline phases. FESEM images reveal an interesting deposition of hexagonal-shaped Al2O3 particles on polished surfaces and complex oxide phases of the fiber network adhering to alumina particles in the form of tails seen on the fracture surfaces. Moreover, the bending strength of 213±21MPa, Vickers hardness of 9.3±0.1MPa and fracture toughness of 6.21±0.12MPa·m1/2 are obtained for the prepared composite.
Investigation of bonding strength and hot corrosion behavior of NiCoCrAlSi high entropy alloy applied on IN-738 superalloy by SPS method
2022, Journal of Alloys and Compounds
Fabrication feasibility of NiCoCrAlSi/IN-738 (HEA-15), NiCoCrAlSi/Al/IN-738 (HEA-15F) joints via plasma spark sintering (SPS) method was investigated in this study. The bonding strength and hot corrosion behavior of these systems are compared with NiCrAlY/IN-738 (NiCrAlY) joint. The mentioned high entropy alloys (HEAs) were fabricated by mechanical alloying method for 40h in Ar atmosphere. The milled powders were then applied on IN-738 superalloy by SPS method at 1170°C and soaking time of 15min with an average thickness of 1.1mm. The microstructural/phase characterization of these samples was evaluated by field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) analysis. The hot corrosion behavior of these joints in 90wt% Na2SO4 −10% wt. NaCl at 800°C for 100h were studied. Bonding strengths were evaluated using the pull-off adhesion test. The lowest amount of hot corrosion was obtained for the HEA-15 joint. The highest thickness of oxide layers after the hot corrosion test was obtained for the NiCrAlY sample (366µm), which was higher than the HEA-15 sample (194µm). High bonding strength of 155MPa was obtained for HEA-15 sample which was higher than that of the other joints. This value was 114MPa for NiCrAlY joint. Contrary to expectations, HEA-15F sample did not show appropriate bonding strength due to the presence of surface oxides in aluminum intermediate layer.
Preparation of mullite/NbN composites through spark plasma sintering
2022, Materials Chemistry and Physics
The main objective of this article is to obtain reaction sintered mullite based ceramics through spark plasma sintering process. 5, 10 and 15wt% NbN particles were mixed with kaolinite and alumina powders as mullite precursor through a wet milling process. The mullite ceramic and composites were fabricated by spark plasma sintering (SPS) method at 1350°C with initial and final applied pressure of 10 and 50MPa, respectively. All of prepared composites showed relative density higher than 99% of theoretical density as well as mullite ceramic. The XRD patterns obtained from sintered composites demonstrated dominant crystalline phase of mullite and NbN and also some low-intensity of alumina peaks were observed. The FESEM images of sintered composites illustrated uniform distribution of reinforcement particles for 5 and 10wt% addition of NbN. While using 15wt% NbN reinforcement phase lead to form some agglomerates areas. The optimum mechanical properties were obtained for composites containing 10wt% NbN as bending strength of 441±36MPa, Vickers hardness of 17.89±0.61GPa and fracture toughness of 3.79±0.12MPam1/2.
Amorphous coatings on tantalum formed by plasma electrolytic oxidation in aluminate electrolyte and high temperature crystallization treatment
2022, Surface and Coatings Technology
In this paper, amorphous coatings on tantalum obtained by plasma electrolytic oxidation (PEO) in alkaline sodium aluminate electrolyte (2–10g/l NaAlO2+2g/l KOH) are investigated. It was found that the amorphous component of the oxide coatings increased with NaAlO2 concentration in the electrolyte. The coatings obtained in the electrolyte of 10g/l NaAlO2+2g/l KOH are completely amorphous. Subsequently, the amorphous coatings were subjected to vacuum heat treatment at 600, 800, 900 and 1300°C to study their crystallization behavior. The results show that crystallization does not occur at 600°C. However, crystallization occurred partially at 800°C and completed at 1300°C, with orthorhombic AlTaO4 as the main phase structure. Nanoindentation tests show that hardness of the coating at dense regions increases after crystallization, but defects and cracks in the coating are also increased after heat treatment. The amorphous coatings have excellent corrosion resistance, but the defects generated in the crystallized coatings are detrimental to the corrosion performance. The reason for the formation of amorphous coatings may be derived from rapid cooling and the glass-forming ability of the binary system of Ta2O5 and Al2O3.
Fabrication of (Ti<inf>x</inf>Zr<inf>1−x</inf>)B<inf>2</inf>-(Zr<inf>x</inf>Ti<inf>1−x</inf>)N composites by reactive spark plasma sintering of ZrB<inf>2</inf>-TiN
2021, Journal of Alloys and Compounds
In this study, microstructural and mechanical properties of (ZrxTi1−x)N-(TixZr1−x)B2 composite fabricated by reactive spark plasma sintering (SPS) of ZrB2 and TiN was investigated. ZrB2 and TiN starting materials with equimolar ratio were sintered at 2000°C for 8min under a pressure of 30MPa. An expansion (about 4%) was observed during the sintering process of the composite in the temperature range between 1290°C and 1625°C, which was attributed to the reaction of the starting materials. XRD pattern of the fabricated composite revealed the formation of TiB2 and ZrN phases after the sintering process. It was found that (Ti0.91Zr0.09)B2 and (Zr0.92Ti0.08)N phases are formed after sintering. High values of Vickers microhardness (28±0.2GPa), flexural strength (706±51MPa) and fracture toughness (8.49±0.92MPam1/2) were achieved for this composite. Fracture of the (ZrxTi1−x)N and (TixZr1−x)B2 phases and crack path deflection mechanisms was founded as dominant toughening mechanisms in this composite.
Role of carbon nanotubes on mechanical properties of SiC-B4C-Ni hybrid composites fabricated by reactive spark plasma sintering
2021, Ceramics International
The present study was conducted to investigate the microstructural and mechanical properties of SiC-45vol%B4C-10vol%Ni and SiC-45vol% B4C-10vol%Ni-5vol% CNT in-situ composites fabricated through reactive spark plasma sintering (SPS) method at 1650°C for 5min. The phase and microstructural characterization of the composites were evaluated utilizing x-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Ultimately, microhardness, flexural strength, and fracture toughness of the composites were measured. Densification behavior of the samples revealed that the initial shrinkage of the composites took place at about 750°C, which is related to the reaction between Ni and SiC phases. XRD results confirmed the formation of Ni2Si phase. The relative density of 98.3±0.32% was achieved for the SiC-B4C-10Ni sample; this value was 97.8±0.62% for the SiC-B4C-10Ni-5CNT sample. The flexural strength of 362±23MPa was achieved for the SiC-B4C-10Ni sample; this value was 369±15MPa for the SiC-B4C-10Ni-5CNT sample. The comparison between the fabricated composites concerning the fracture toughness indicated further fracture toughness of the SiC-B4C-10Ni-5CNT sample (5.82±0.32MPam1/2) than that of the SiC-B4C-10Ni sample (3.35±0.56MPam1/2). Formation of micro-cracks, crack path deflection, and CNT bridging was the main toughening mechanisms in the SiC-B4C-10Ni-5CNT sample.
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Ceramics International, Volume 45, Issue 16, 2019, pp. 20844-20854
In this study, the microstructural and mechanical properties of three different mullite matrix composites were investigated. Accordingly, Mullite-TiN-CNT, Mullite-TiN-TiB2-CNT and Mullite-TiN-TiB2-ZrB2-CNT composites with 10 wt % of each TiN, TiB2 and ZrB2 reinforcement particles as well as 1 wt % CNT were prepared by the spark plasma sintering (SPS) technique. The sintering processes were conducted at 1350 °C for 5 min with a mean heating rate of 60 °C/min. The relative densities of the composites achieved were higher than 97% of theoretical density. The results of mechanical properties of the fabricated composites showed that Mul-TiN-TiB2-ZrB2-CNT composites obtained the highest hardness and fracture toughness values. XRD results confirmed the presence of mullite, TiN, TiB2 and ZrB2 phases without any additional reactions between reinforcement and matrix phases. Microstructural studies demonstrated the uniform distribution of reinforcing phases in the matrix for all composites. The fracture surface micrographs revealed the dominating transgranular fracture mode indicated the strong adhesion of the reinforcing particles to the matrix. Pulling out of CNTs was also observed in the fracture surface of composites, which plays a vital role in the fracture energy absorption and joining of interfaces.
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Materials Science and Engineering: A, Volume 627, 2015, pp. 27-30
In the present work, aluminum-10wt% ZrB2-1wt% Co composite was prepared by two different sintering methods: microwave and spark plasma, and the relative density of 97±0.3% TD (at 640°C) and 98±0.3% TD (at 450°C) was obtained, respectively and XRD analysis revealed Al and ZrB2 as the only crystalline phases. Mechanical investigations revealed that the bending and compressive strength of SPS samples were 275±10 and 381±16MPa, respectively, which were higher than those of microwave samples. The microhardness values of SPS and microwave sintered specimens were obtained 160 and 110±12 Vickers, respectively. Microstructural investigations revealed a homogeneous distribution of ZrB2 particles in the aluminum matrix in both methods.
Microwave and spark plasma sintering of carbon nanotube and graphene reinforced aluminum matrix composite
Archives of Civil and Mechanical Engineering, Volume 18, Issue 4, 2018, pp. 1042-1054
Graphene and carbon nanotube due to their outstanding mechanical performance were used as reinforcement in aluminum (Al) based composite through spark plasma sintering (SPS), microwave (MW) and conventional techniques. The initial compositions of Al-1wt% CNT, Al-1wt% GNP and Al-1wt% CNT–1wt% GNP were mixed by a high energy ultrasonic device and mixer mill to achieve homogenous dispersion. The SPS, MW and conventional processes were conducted at almost 450, 600 and 700°C, respectively. The maximum relative density (99.7±0.2% of theoretical density) and bending strength (337±11MPa) obtained by SPS, while maximum microhardness of 221±11 Vickers achieved by microwave for Al-1wt% CNT–1wt% GNP hybrid composite. X-ray diffraction (XRD) examinations identified Al as the only dominant phase accompanied by very low intensity peaks of Al4C3. Field emission scanning electron microscopy (FESEM) micrographs demonstrated uniform distribution of GNP as well as CNT reinforcement in spark plasma sintered samples.
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In the present work, the hot corrosion behavior of two types of multilayer plasma sprayed TBC were investigated and compared with functionally graded and conventional TBCs. These kinds of multilayer coatings consisted of nano/μ alumina as a top coat on YSZ layer, a metallic bond coat and a functionally graded intermediate layer deposited between YSZ and bond coat layers. All the layers were sprayed on the Ni-base super alloy substrate. The hot corrosion resistance of the plasma sprayed coatings was examined at 1050°C for 40h, using a fused mixture of 45wt% Na2SO4 + 55wt%V2O5. Before and after hot corrosion, the microstructure and phase analysis of the coating were studied using scanning electron microscope and X-ray diffractometer. The results showed that, the Al2O3 top layer acted as a barrier against the infiltration of the molten salt into the YSZ layer during exposure to the molten salt mixture at the high temperature and the multilayer coatings of zirconia/alumina with the nanostructured alumina as a top coat showed higher hot corrosion resistance. Also, the failure mechanisms of the functionally graded coating and duplex TBC were investigated. The spallation occurred between the graded layer and the bond coat/top coat in functionally graded TBC and duplex TBC, respectively.
Effects of ZrB2 reinforcement on microstructure and mechanical properties of a spark plasma sintered mullite-CNT composite
Ceramics International, Volume 45, Issue 13, 2019, pp. 16015-16021
A high density 10 wt% ZrB2 and 1 wt%. CNT-reinforced mullite-based composite was prepared by spark plasma sintering (SPS) at temperature of 1350 °C, average heating rate of 60 °C/min and a soaking time of 5 min. Under these conditions, the sintered composite obtained a high hardness (16.24 ± 0.12 GPa), fracture toughness (4.18 ± 0.51 MPa m1/2) and flexural strength (488 ± 21 MPa). The results of FESEM images showed a uniform distribution of the reinforcement particles in the composite. The resulting CNTs survived the sintering process and did not undergo any transformation. A transgranular fracture was predominantly observed in the fractured surface micrographs of the composite. The CNTs pullout and crack-bridging toughening mechanisms were also observed in the composite, which could have a significant contribution to the fracture energy and the interfacial adhesion.
© 2018 Elsevier Ltd and Techna Group S.r.l. All rights reserved.
What is the method of spark plasma sintering? ›
Spark plasma sintering (SPS) is a pressure-assisted pulsed-current process in which the powder samples are loaded in an electrically conducting die and sintered under a uniaxial pressure [4–8].What is the heating rate of spark plasma sintering? ›
Spark Plasma Sintering Technique (SPS)
Sumitomo Heavy Industries Ltd in 1990 produced the first commercial SPS machine . Heating rate of 1000º C/min is achieved depending on the geometry of die, punches and power supply.
In a general sense, microwave sintering increases the densification of the material at lower dwell temperatures when compared to conventional sintering [13, 14], employing shorter times and less energy [15, 16], and resulting in an improvement of the microstructure and mechanical properties [17, 18].What are the advantages and disadvantages of spark? ›
|Speed||No automatic optimization process|
|Ease of Use||File Management System|
|Advanced Analytics||Fewer Algorithms|
|Dynamic in Nature||Small Files Issue|
Microwave sintering Microwave sintering is to use the dielectric loss of the ceramic material in the microwave electromagnetic field to heat the material to the sintering temperature to achieve sintering and densification.What are the 3 principal sintering processes? ›
Basically, sintering processes can be divided into three types: solid state sintering, liquid phase sintering and viscous sintering, which are all widely used in the industry. The driving force of sintering is the reduction in the total interfacial energy, which occurs via densification and grain growth.What are the parameters for spark plasma sintering? ›
The optimum spark plasma sintering factors were a temperature of 500°C, a pressure of 30 MPa, a dwelling time of 8 minutes, and a heat rate of 160 °C/min, resulting in an extreme density of 2.71 g/cm3 and a maximum microhardness of 38.61 HV (0.38 GPa).What is the best sintering temperature? ›
Heating these in a furnace -- a process known as sintering -- bonds the powder grains together, to create hard components ready for use. Sintering of iron based PM parts is usually done at around 2020-2100°F.What is the highest sintering temperature? ›
Furnace sintering can achieve temperatures of 2700 °C. Sintering furnaces can also heat with microwaves instead of heating elements.What are some benefits of high temperature sintering sinter hardening microwave sintering? ›
Microwave sintering has advantages like enhanced diffusion processes, reduced energy consumption, and rapid heating rates. Microwave sintering considerably reduces processing times, decreases sintering temperatures, improves physical and mechanical properties, and has lower environmental hazards.
What are the disadvantages of microwave method? ›
Microwaves do have some downsides. For example, they may not be as effective as other cooking methods at killing bacteria and other pathogens that may lead to food poisoning. That's because the heat tends to be lower and the cooking time much shorter. Sometimes, food heats unevenly.What are the disadvantages of sintering? ›
- High cost of raw materials.
- Necessity to maintain whole process in special atmosphere.
- Complexity of production of big parts.
- To receive parts without admixtures it is required to have clean (100%) powder.
The major disadvantage of microwave heating is nonuniform temperature distribution resulting in hot and cold spots in foods.What are disadvantages of Spark? ›
- Spark is built for big data and Scala engineers,not for analytics teams. ...
- Spark is not a stand-alone solution. ...
- Expect a very long time-to-value. ...
- Disconnect between the people who need the data and the people who can access it. ...
- Higher costs than expected. ...
- SQL and visual UI instead of coding in Scala.
Some of the drawbacks of Apache Spark are there is no support for real-time processing, Problem with small file, no dedicated File management system, Expensive and much more due to these limitations of Apache Spark, industries have started shifting to Apache Flink– 4G of Big Data.What is the main advantage of Spark? ›
Apache Spark is a powerful open-source analytics engine that has become increasingly popular in recent years. There are many reasons for Spark's popularity, but some of the most important benefits include its speed, ease of use, and ability to handle large data sets.What are the four stages of sintering? ›
- Pre-sintering stage (Removal of forming agent and pre-sintering stage) ...
- Solid-phase sintering stage (800℃——eutectic temperature) ...
- Liquid phase sintering stage (eutectic temperature - sintering temperature) ...
- Cooling stage ( Sintering temperature - room temperature)
Sintering a metal for 3D printing could help to save energy compared to melting the same metal, and allows for greater control and consistency, since the material isn't being completely liquefied. However, this leaves more microscopic gaps than the full liquefaction caused by melting would.What is the difference between sintering and heat treatment? ›
Sintering is the process of welding together small particles of a metal by applying heat below the melting point of the metal. Annealing is a heat treatment process in which we have to heat a metal to a predominant temperature, hold for some time and then cool it down in order to improve ductility.What is the main advantage of spark? ›
Apache Spark is a powerful open-source analytics engine that has become increasingly popular in recent years. There are many reasons for Spark's popularity, but some of the most important benefits include its speed, ease of use, and ability to handle large data sets.
What are the advantages of spark in machine learning? ›
- Speed. Engineered from the bottom-up for performance, Spark can be 100x faster than Hadoop for large scale data processing by exploiting in memory computing and other optimizations. ...
- Ease of Use. Spark has easy-to-use APIs for operating on large datasets. ...
- A Unified Engine.
- Outstanding speed and performance. In Big Data, speed and processing are two of the most important components. ...
- Developer-Friendly Tools. ...
- Libraries. ...
- Structured Streaming. ...
- Handle Analytic Challenges. ...
- Easy to use. ...
- Support for multiple languages. ...
- Support for Lazy Evaluation.
Normally, SPS with fan built-in has a certain weakness such as unavoidable noise, vibration, additional power consumption, unexpected mechanical failure, short term reliability, dust debris, etc.What are some characteristics of Spark that help improve performance? ›
- Serialization. Serialization plays an important role in the performance for any distributed application. ...
- API selection. ...
- Advance Variable. ...
- Cache and Persist. ...
- ByKey Operation. ...
- File Format selection. ...
- Garbage Collection Tuning. ...
- Level of Parallelism.
- Cost. Cost effectiveness is another factor that needs to be considered in Apache Spark. ...
- Small File Issue. Issues with small files are common when Apache Spark is combined with Hadoop. ...
- Lack of Real Time Processing. ...
- No File Management System. ...
- Manual Optimization. ...
- Pressure Control.
- Ingesting data in a publish-subscribe model: In those cases, you have multiple sources and multiple destinations moving millions of data in a short time. ...
- Low computing capacity: The default processing on Apache Spark is in the cluster memory.
Spark architecture consists of four components, including the spark driver, executors, cluster administrators, and worker nodes.What are the common uses of Spark? ›
Apache Spark is beneficial for small as well as large enterprise. Spark offers a complete solution to many of the common problems like ETL and warehousing, Stream data processing, common use case of supervised and unsupervised learning for data analytics and predictive modelling.Is Spark a good ETL tool? ›
They are an integral piece of an effective ETL process because they allow for effective and accurate aggregating of data from multiple sources.Why use Databricks instead of Spark? ›
Databricks provides notebooks usable with your cluster. It is possible to configure standalone notebook instances to run code via a standalone Spark instance but Databricks handles the necessary configuration, making the task much easier.
Why we use Spark instead of Hadoop? ›
Spark has its machine learning library called MLib, whereas Hadoop must be interfaced with an external machine learning library, for example, Apache Mahout. As Spark is faster than Hadoop, it is well capable of handling advanced analytics operations like real-time data processing when compared to Hadoop.