Effect and corresponding mechanism of NaCl additive on boron carbide powder synthesis via carbothermal reduction

2019 ◽  
Vol 97 ◽  
pp. 107458 ◽  
Author(s):  
Xin Li ◽  
Shuai Wang ◽  
Dan Nie ◽  
Kun Liu ◽  
Shu Yan ◽  
...  
Keyword(s):  
Boron Carbide ◽  
Carbothermal Reduction ◽  
Carbide Powder ◽  
Powder Synthesis

Effect of Molecular Structure of Polyols with Different Molecular Characteristics on Synthesis of Boron Carbide Powder

2013 ◽  
Vol 534 ◽  
pp. 61-65 ◽  
Author(s):  
Masaki Kakiage ◽  
Naoki Tahara ◽  
Yusuke Tominaga ◽  
Satomi Yanagidani ◽  
Ikuo Yanase ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Thermal Decomposition ◽  
Boron Carbide ◽  
Carbothermal Reduction ◽  
Poly Vinyl Alcohol ◽  
Molecular Characteristics ◽  
Carbide Powder ◽  
Excess Carbon ◽  
Condensed Product ◽  
Crystalline Boron

Crystalline boron carbide (B4C) powder was synthesized by the carbothermal reduction of condensed products formed from boric acid (H3BO3) and polyols with different molecular characteristics, i.e., glycerin, mannitol, and poly (vinyl alcohol) (PVA). The effect of the molecular structure of the polyol on the thermal decomposition conditions and the obtained morphology of the B4C powder was discussed in this study. The thermal decomposition in air of each condensed product was performed before the carbothermal reduction in order to eliminate the excess carbon, where the decomposition conditions varied with the type of polyol. Crystalline B4C powder with less residual free carbon was synthesized from the thermally decomposed products by heating at 1250 °C for 5 h in an Ar flow. The thermal decomposition conditions and the particle size of the obtained B4C powder reflected the molecular characteristics of the polyols.

Processing factors influencing the free carbon contents in boron carbide powder by rapid carbothermal reduction

2016 ◽  
Vol 61 ◽  
pp. 14-20 ◽  
Author(s):  
Yong Gao ◽  
Anthony Etzold ◽  
Tyler Munhollon ◽  
William Rafaniello ◽  
Richard Haber
Keyword(s):  
Boron Carbide ◽  
Carbothermal Reduction ◽  
Free Carbon ◽  
Carbide Powder ◽  
Factors Influencing ◽  
Processing Factors

Nanozirconium Carbide Powder Synthesis via Carbothermal Route

2013 ◽  
Vol 334-335 ◽  
pp. 381-386 ◽  
Author(s):  
F. Arianpour ◽  
F. Kazemi ◽  
Hamid Reza Rezaie ◽  
A. Asjodi ◽  
J. Liu
Keyword(s):  
Carbon Sources ◽  
Zirconium Carbide ◽  
Carbide Powder ◽  
Carbide Formation ◽  
Matrix Composites ◽  
Powder Synthesis ◽  
High Refractoriness ◽  
Heat Treated ◽  
Crystallite Sizes ◽  
20 Nm

Zirconium carbide (ZrC) has extended application in many ceramic and metal matrix composites especially used for ultra high temperature conditions. The synthesis of zirconium carbide powder is costly and difficult because of its high refractoriness and chemically inert properties. In this research, the synthesis of zirconium carbide nanopowder at low temperature via carbothermal reduction route was investigated according to thermodynamic data. The starting materials were zirconium acetate and sucrose as zirconium and carbon sources, respectively. After preparation of different carbon/zirconium ratio containing precursors, the dried precursors were heat treated at 1400°C and vacuum atmosphere. Also the ZrC formation was followed by thermal analysis of the produced precursors. The phase evolutions and microstructural studies were carried out using X-ray diffraction and scanning electron microscopy. The results showed that it is possible to synthesis zirconium carbide nanopowder with round shape and crystallite sizes smaller than 20 nm at low temperatures. Also according to thermodynamic calculations, it was concluded that by applying vacuum condition, the zirconium carbide formation can occur at less than 1000°C which is very effective on the size reducing of produced ZrC nanopowders.

scholarly journals Multi-Objective Optimization of Process Parameters for Powder Mixed Electrical Discharge Machining of Inconel X-750 Alloy Using Taguchi-Topsis Approach

2021 ◽  
Vol 71 (1) ◽  
pp. 1-18
Author(s):  
Basha Shaik Khadar ◽  
Raju M. V. Jagannadha ◽  
Kolli Murahari
Keyword(s):  
Boron Carbide ◽  
Process Parameters ◽  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Optimization Technique ◽  
Dielectric Fluid ◽  
Carbide Powder ◽  
Powder Concentration ◽  
Pulse On Time ◽  
Pulse Off Time

Abstract The paper investigates the influence of boron carbide powder (B4C) mixed in dielectric fluid on EDM of Inconel X-750 alloy. The process parameters selected as discharge current (Ip), pulse on time(Ton), pulse off time(Toff), boron carbide(B4C) powder concentration to examine their performance responses on Material Removal Rate (MRR), Surface Roughness(Ra) and Recast Layer Thickness (RLT).In this study, o examine the process parameters which influence the EDM process during machining of Inconel X-750 alloy using combined techniques of Taguchi and similarity to ideal solutions (TOPSIS).Analysis of variance (ANOVA) was conducted on multi-optimization technique of Taguchi-TOPSIS. ANOVA results identified the best process parameters and their percentages. It developed the mathematical equation on Taguchi-TOPSIS performance characteristics results. The multi optimization results indicated that Ip and Toff are more significant parameters; V, and Ton parameters are less significant. Finally, surface structures were studied at optimized EDM conditions by using scanning electron microscope (SEM).

Purification of Attrition Milled Nano-size Boron Carbide Powder

2012 ◽  
Vol 05 ◽  
pp. 94-101 ◽  
Author(s):  
A. Sokhansanj ◽  
A.M. Hadian
Keyword(s):  
Chemical Analysis ◽  
Boron Carbide ◽  
Sintering Temperature ◽  
Milled Powder ◽  
Carbide Powder ◽  
Sintering Behavior ◽  
Sintered Ceramic ◽  
Weight Percentage ◽  
Wide Range ◽  
Nano Size

Boron carbide is one of the advanced ceramic materials which is used in a wide range of applications. However, this material needs a high sintering temperature (~2200°C). Using nano-size powders for producing ceramic parts results in lowering sintering temperature and also enhances toughness and hardness of the material. One of the methods for producing ceramic nano powders is attrition milling. However, as the milling balls and wall are made of steel, some impurities specially iron will be introduced to the powder during milling. Chemical analysis of the milled powder shows that more than 33wt% of the powder consists of iron. These uncontrolled impurities affect the mechanical and physical properties of sintered ceramic parts that are made of such a powder. Therefore, these impurities must be removed from the powder. Hydro metallurgical beneficiation technique with two different solvents has been used for purification of the powder. The result of chemical analysis after purification showed that the weight percentage of iron in powder dropped to 9% and 0.8% (depending on the solvents). Moreover, the sintering behavior of hot-pressed boron carbide powder with different percentages of iron as sintering aid has been studied. The results showed excellent densification and hardness of the sintered parts.

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