scholarly journals Influence of Various Process Parameters on the Density of Sintered Aluminium Alloys

10.14311/1604 ◽  
2012 ◽  
Vol 52 (4) ◽  
Author(s):  
Mateusz Laska ◽  
Jan Kazior
Keyword(s):  
Sintered Density ◽  
Sintering Temperature ◽  
Compaction Pressure ◽  
Nitrogen Atmosphere ◽  
Chemical Compositions ◽  
Green Density ◽  
Heating And Cooling ◽  
Wide Range ◽  
Different Temperatures ◽  
Metallurgy Industry

This paper presents the results of density measurements carried out on Alumix sintered parts. ECKA Alumix aluminium powders were used because of their wide application in the powder metallurgy industry. The compacts were produced using a wide range of compaction pressures for three different chemical compositions. The compacts were then sintered under a pure dry nitrogen atmosphere at three different temperatures. The heating and cooling rates were the same throughout the entire test. The results showed that the green density increases with compaction pressure, but that sintered density is independent of green density (compaction pressure) for each sintering temperature.

scholarly journals Sustainable Modularity Approach to Facilities Development Based on Geothermal Energy Potential

2021 ◽  
Vol 11 (6) ◽  
pp. 2691
Author(s):  
Nataša Ćuković Ignjatović ◽  
Ana Vranješ ◽  
Dušan Ignjatović ◽  
Dejan Milenić ◽  
Olivera Krunić
Keyword(s):  
Geothermal Energy ◽  
Architectural Design ◽  
Pannonian Basin ◽  
Thermal Power ◽  
Chemical Compositions ◽  
Energy Potential ◽  
Southeastern Part ◽  
Geothermal Resources ◽  
Heating And Cooling ◽  
Different Temperatures

The study presented in this paper assessed the multidisciplinary approach of geothermal potential in the area of the most southeastern part of the Pannonian basin, focused on resources utilization. This study aims to present a method for the cascade use of geothermal energy as a source of thermal energy for space heating and cooling and as a resource for balneological purposes. Two particular sites were selected—one in a natural environment; the other within a small settlement. Geothermal resources come from different types of reservoirs having different temperatures and chemical compositions. At the first site, a geothermal spring with a temperature of 20.5 °C is considered for heat pump utilization, while at the second site, a geothermal well with a temperature of 54 °C is suitable for direct use. The calculated thermal power, which can be obtained from geothermal energy is in the range of 300 to 950 kW. The development concept was proposed with an architectural design to enable sustainable energy efficient development of wellness and spa/medical facilities that can be supported by local authorities. The resulting energy heating needs for different scenarios were 16–105 kW, which can be met in full by the use of geothermal energy.

scholarly journals Effect of Sintering Temperature on Metal-Insulator Phase Transition in La1-xCaxMnO3 Perovskites

2020 ◽  
Vol 2 (1) ◽  
pp. 37-42
Author(s):  
Arunachalam M ◽  
Thamilmaran P ◽  
Sakthipandi K
Keyword(s):  
Phase Transition ◽  
Bulk Modulus ◽  
Sintering Temperature ◽  
Magnetic Sensors ◽  
Temperature Dependent ◽  
Metal Insulator ◽  
Wide Range ◽  
Different Temperatures ◽  
Insulator Phase Transition

Lanthanum calcium based perovskites are found to be advantageous for the possible applications in magnetic sensors/reading heads, cathodes in solid oxide fuel cells, and frequency switching devices. In the present investigation La0.3Ca0.7MnO3 perovskites were synthesised through solid state reaction and sintered at four different temperatures such as 900, 1000, 1100 and 1200˚ C. X-ray powder diffraction pattern confirms that the prepared La0.3Ca0.7MnO3 perovskites have orthorhombic structure with Pnma space group. Ultrasonic in-situ measurements have been carried out on the La0.3Ca0.7MnO3 perovskites over wide range of temperature and elastic constants such as bulk modulus of the prepared La0.3Ca0.7MnO3 perovskites was obtained as function of temperature. The temperature-dependent bulk modulus has shown an interesting anomaly at the metal-insulator phase transition. The metal insulator transition temperature derived from temperature-dependent bulk modulus increases from temperature 352˚ C to 367˚ C with the increase of sintering temperature from 900 to 1200˚ C.

Warm Compacting Behaviors and Sintering Performance of 316L Stainless Steel Powder

2012 ◽  
Vol 538-541 ◽  
pp. 1088-1091
Author(s):  
Mei Yuan Ke
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
316L Stainless Steel ◽  
Sintered Density ◽  
Steel Powder ◽  
Nitrogen Atmosphere ◽  
Green Density ◽  
Cold Compaction ◽  
Warm Compaction ◽  
Made In

Warm compacting behavior and sintering performance of 316L stainless steel powders were studied. Results showed that green density and strength of samples made in warm compaction were much higher than that in cold compaction. Under pressure of 700MPa, green density and strength in warm compaction were 7.01 g•cm-3and 30.7MPa, which were higher than cold compaction by 0.19 g•cm-3and 10.7MPa. When sintered in hydrogen-nitrogen atmosphere for 60 minutes, sintered density, tensile strength and elongation all increased with the rise of sintering temperature. At 1300°C, Sintered density, tensile strength and elongation were 7.42 g•cm-3, 545MPa, 28.0%, respectively.

An experimental investigation of the fabrication of biodegradable zinc–hydroxyapatite composite material using microwave sintering

2020 ◽  
Vol 234 (14) ◽  
pp. 2863-2880 ◽  
Author(s):  
Dayanidhi Krishana Pathak ◽  
Pulak Mohan Pandey
Keyword(s):  
Yield Strength ◽  
Heating Rate ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Microwave Sintering ◽  
Compaction Pressure ◽  
Optimum Process ◽  
Compressive Yield Strength ◽  
Process Factors

The present work focuses on the fabrication of zinc–hydroxyapatite biodegradable composite with the use of pressureless microwave sintering for the orthopedic load-bearing application. The samples were prepared using the powder metallurgy process. The powders of both materials were homogeneously mixed in the quantified proportions to form the uniform mixture. For the fabrication of samples, the planning of experiments was done with the central composite design. The effect of process factors such as the weight percentage of hydroxyapatite, compaction pressure, and microwave sintering factors such as sintering temperature, heating rate, and soaking time on the compressive yield strength and sintered density was evaluated. Cylindrical samples were prepared for compression testing. The experimental results exhibited the increase in the compressive yield strength as well as the sintered density with the decrease in the hydroxyapatite percentage and an increase in the compaction pressure. The results also revealed that the compressive yield strength and sintered density were found to be increased as the heating rate and sintering temperature increased. Sample characterization was carried out for phase determination and composition of the elements. The optimum process factors were obtained after the regression analysis, and the results of the optimum process factors were also verified with the confirmation experiments. The in vitro corrosion testing of the sample prepared with optimum factors was also carried out in the simulated body fluid at a temperature of 37 ± 0.5 ℃. The fabricated sample showed a good agreement between the mechanical and degradation properties as required for a human bone.

scholarly journals Temperature-influenced Substitution of Si in Ti3(Si,Al)C2  Solid Solution

2020 ◽  
Author(s):  
Jun JI ◽  
Zirun YANG ◽  
Zhenyu ZHANG ◽  
Dechun LI ◽  
Zhi Wang ◽  
...  
Keyword(s):  
Solid Solution ◽  
Sintering Temperature ◽  
Lattice Parameter ◽  
Chemical Compositions ◽  
X Rays ◽  
Experiment Data ◽  
Substitution Process ◽  
Vegard’S Law ◽  
Different Temperatures ◽  
Scanning Electron

Abstract High-pure Ti3(Si,Al)C2 solid solutions were synthesized in the range of 1473 to 1773K. The microstructures and chemical compositions of all samples were characterized by X-rays diffraction (XRD) and scanning electron microscope (SEM). It was worthy noted that experimentally determined lattice parameter c of Ti3(Si,Al)C2 crystal decreased with the increasing of sintering temperature. The contents of Si and Al elements in solid solution were conducted by Vegard’s Law. Gibbs energy differences (△G) of substitution behaviors of Si at different temperatures were also listed. With the increase of temperature, △G of Eq. Ti3(Si0.75Al0.25)C2+0.25Si→Ti3SiC2+0.25Al were negative and decreased gradually, which means that the transformation from Ti3(Si,Al)C2 to Ti3SiC2 was spontaneous and had a greater tendency in higher temperatures. By analyzing the experiment data, a possible mechanism of the substitution process of Si in various temperatures was determined.

Reduction of Sintering Temperature of Porous Tungsten Skeleton Used for Production of W-Cu Composites by Ultra High Compaction Pressure of Tungsten Powder

2011 ◽  
Vol 264-265 ◽  
pp. 807-812 ◽  
Author(s):  
A. Ghaderi Hamidi ◽  
H. Arabi ◽  
Saeed Rastegari
Keyword(s):  
Sintering Temperature ◽  
Tungsten Powder ◽  
Compaction Pressure ◽  
Green Density ◽  
Optimum Structure ◽  
Cold Isostatic Press ◽  
Copper Melt ◽  
Method Of Production ◽  
Lower Temperature ◽  
Structural Heterogeneities

Production of tungsten-copper composites includes compaction and sintering of tungsten powder, then infiltration of copper melt within the tungsten skeleton. Sintering of tungsten compacts usually requires a temperature range of 1800 to 2200°C. This means, this process not only needs advanced heating equipments and high expenses but also may cause formation of defects such as structural heterogeneities, cracks and distortions. In this research the required sintering temperature was reduced to 1500°C by increasing compaction pressure. Also the relation between compaction pressure applied through a cold isostatic press (CIP), and green density of the compacted tungsten powder was established. In addition, the effect of various pressures on densification of tungsten compacts during sintering at moderate temperature, i.e. 1500°C was studied, and the optimum structure for infiltration was chosen. Then by infiltrating Cu melt into the optimized W-skeleton, composites of W-Cu having a density of 17.2 gr/cm3 were produced. This method of production provides an innovative technique for obtaining a desired density of infiltrable skeleton, sinterable at a lower temperature than the temperatures used for the conventionally packed W-compacts without introducing structural inhomogeneities during sintering. Study of some characteristics of the optimized composite produced by the above technique satisfied the requirements for production of W-Cu composites having all the specifications given for these types of composites produced at higher temperatures than 1500°C.

Study on High Performance Warm Compacted Fe-2Ni-2Cu-1Mo-1C Powder Metallurgy Materials

2007 ◽  
Vol 353-358 ◽  
pp. 1621-1624
Author(s):  
Zhi Yu Xiao ◽  
Jun Wang ◽  
Shu Hua Luo ◽  
Li Pin Wen ◽  
Yuan Yuan Li
Keyword(s):  
High Performance ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Green Density ◽  
Spring Back ◽  
Mixed Powder ◽  
Sintering Time ◽  
Compact Density ◽  
Dimension Change ◽  
Compacting Pressure

Warm compacting and sintering behaviors of pre-mixed Fe-2Ni-2Cu-1Mo-1C powders were studied. Results showed that green density increased with compacting temperature and then fell slightly; the maximum green density was obtained at about 120°C. Green compact density and spring back effect of the pre-mixed powder increased gradually as the compacting pressure increased. Sintered density first increased and then fell as the temperatures went up under different sintering temperatures for 50 minutes, but the trends of sintering dilatation were first reduced and then increased. Sintered density first reduced and then increased with the prolonged sintering time at 1300°C, but the trends of dimension change after sintering were the very reverse. Tensile strength, elongation and hardness of the warm compacted Fe-2Ni-2Cu-1Mo-1C materials generally increased as sintering temperature and sintering time went up.

Phase analysis and microstructure study of sintered Ni-Cr composites containing MoS2, Ag and CaF2 additives as solid lubricants

2020 ◽  
Vol 14 (2) ◽  
pp. 6548-6556
Author(s):  
Wan Farhana Mohamad ◽  
Amir Azam Khan ◽  
Faiz Ahmad ◽  
Abdullah Yassin
Keyword(s):  
Relative Density ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Solid Lubricants ◽  
Xrd Analysis ◽  
Powder Metallurgy Method ◽  
X Ray Diffraction ◽  
Hardness Tester ◽  
Maximum Value ◽  
Different Temperatures

Ni-Cr based composites with and without the addition of solid lubricants (MoS2, Ag and CaF2) were prepared by powder metallurgy method. The samples were sintered at different temperatures (1000oC, 1100oC and 1200oC) under controlled atmosphere and various holding times. The physical properties such as sintered density, relative density and porosity were studied. The microstructures and phase studies of the Ni-Cr based composites were conducted using Scanning Electron Microscope (SEM) and X-Ray Diffraction Analysis (XRD) while the hardness of the composites was measured by the Vickers Micro Hardness Tester. The results revealed that as the sintering temperature was increased, the sintered density, relative density and hardness also increased while the porosity was reduced. At the sintering temperature of 1200oC, the relative density reached its maximum value. SEM and XRD analysis confirmed the existence of MoS2 and Ag in sintered samples. MoS2 and Ag were not mainly dissolved and/or decomposed even after sintering at 1200oC

Tribological Properties of PM Cu-Based Dry Friction Clutch

2013 ◽  
Vol 545 ◽  
pp. 163-170 ◽  
Author(s):  
Jirapat Prapai ◽  
Monnapas Morakotjinda ◽  
Thanyaporn Yotkaew ◽  
Bhanu Vetayanukul ◽  
Ruangdaj Tongsri ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Wear Rate ◽  
Tribological Properties ◽  
Dry Friction ◽  
Sintered Density ◽  
Sintering Temperature ◽  
Chemical Compositions ◽  
Friction Clutch ◽  
Frictional Materials ◽  
Dry Friction Clutch

Sintered Cu-based frictional materials were developed by using powder metallurgy (PM) method. The materials are aimed for application in a passenger car as a dry friction clutch. Effects of sintering temperature and composition on mechanical and tribological properties were determined. It was found that improper frictional material formulations caused inferior properties, particularly when the sintering temperatures were increased. Admixing of high Sn content (8 wt. %) resulted in decreases of sintered density and hardness with increasing sintering temperature. High Sn contents caused swelling of the sintered materials. Tribological properties (friction coefficient and wear rate) of the sintered specimens of the investigated materials were insensitive to sintering temperatures in the range of 800-950 °C but they were strongly influenced by chemical compositions. Addition of 3 wt. % graphite lowered the friction coefficient, which subsequently lowered the wear rate of the sintered material. To increase friction coefficient, one of the crucial properties of the dry friction clutch, of the sintered Cu-based frictional materials, two approaches were employed. In the first approach, substitution of graphite by SiO2 powders could improve the material friction coefficient. In the second approach, decreases of graphite content from 3 to 1 wt. % and of Sn content from 8 to 2 wt. % were conducted. The latter approach not only improved friction coefficient but also improved sintered density and hardness of the Cu-based frictional materials.

Effect of Sintering Temperature on the Formation of Intermetallics in Al-Fe-B Nanocomposite

2014 ◽  
Vol 802 ◽  
pp. 130-134
Author(s):  
J. Abenojar ◽  
M.A. Martínez ◽  
A.J. Criado ◽  
F. Velasco
Keyword(s):  
Hot Rolling ◽  
Ternary Phase ◽  
Sintering Temperature ◽  
Ternary Phase Diagram ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
Corrosion Properties ◽  
Dimensional Changes ◽  
Wide Range ◽  
Different Temperatures

Mixing and sintering aluminium and 20% mechanically alloyed Fe/B nanoparticles provokes the formation of intermetallics in the aluminium matrix when following a powder metallurgy route. Materials were sintered in a wide range of temperatures (from 600 to 1100 oC). Previous studies have shown that these materials present neither important dimensional changes during sintering nor significant differences in mechanical properties. However, sintering temperature strongly affects corrosion resistance and hot rolling capability. Low sintering temperature provides nanocomposites with lower corrosion properties and hot rolling capability. In this work the nanocomposites obtained at different temperatures were characterized by X-ray diffraction. This technique allows following the formation of different intermetallics at each temperature, since being non-equilibrium processes, the use of ternary phase diagram of these elements is not possible.

Sign in / Sign up

Export Citation Format

Share Document