Study on the Gel Casting Process of Silicon Carbide

2016 ◽  
Vol 697 ◽  
pp. 138-142 ◽  
Author(s):  
Han Li ◽  
Hong Zhao Xu ◽  
Chang Ling Zhou ◽  
Yan Yan Wang
Keyword(s):  
Silicon Carbide ◽  
High Hardness ◽  
High Strength ◽  
Casting Process ◽  
Uniform Structure ◽  
Modeling Technology ◽  
Gel Casting ◽  
Low Thermal Expansion ◽  
Complex Shapes ◽  
Dry Pressing

Silicon carbide possess high performances such as high hardness and strength, oxidation and high temperature resistance, high thermal conductivity and low thermal expansion coefficient. Widely used methods of molding green body for sintered pressureless bonded silicon carbide comprise dry pressing molding and casting molding. The former fails in preparation of complex shapes, while those prepared by casting molding are prone to have defects such as nonuniformity of density and easy cracking. Gel-casting is a net-shape modeling technology caused by the polymerization of organic monomer (acrylamide). The green bodies molded by gel-casting have uniform structure, high density, high strength and machinability. In this study, gel casting molding and pressureless sintering were used to prepare silicon carbide. The effect of the parameters of gel casting and sintering on the microstructure of the obtained silicon carbide was examined

Synthesis, Characterization and Mechanical Properties of Silicon Carbide Nanowires

2010 ◽  
Author(s):  
Huan Zhang ◽  
Weiqiang Ding ◽  
Daryush Aidun
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Silicon Carbide ◽  
Physical And Mechanical Properties ◽  
High Hardness ◽  
High Strength ◽  
Harsh Environments ◽  
Low Density ◽  
Low Thermal Expansion ◽  
Oxidation And Corrosion

Silicon carbide (SiC) material has many outstanding physical and mechanical properties such as high strength, high hardness, low density, high thermal conductivity, low thermal expansion coefficient, large band-gap, and excellent oxidation and corrosion resistances [1–3]. It is a leading material for components and devices operating at high temperature, high power and under harsh environments [4–5]. Micro-sized SiC particles and whiskers are commonly used as reinforcement materials for ceramics, metals and alloys in various structural and tribological applications [6–7].

scholarly journals Fatigue and Fracture Behavior of Al6061-B4C Aluminium Matrix Composites

2020 ◽  
Vol 9 (4) ◽  
pp. 2121-2125
Keyword(s):  
Fracture Toughness ◽  
Metal Matrix Composites ◽  
Metal Matrix ◽  
Density Ratio ◽  
High Hardness ◽  
High Strength ◽  
Casting Process ◽  
Matrix Composites ◽  
Reaction Products ◽  
Automobile Engineering

In the present day engineering design and development activities many Scientists, Researchers and Engineers are striving hard to develop new and better engineering materials, which accomplishes high strength, low weight and energy efficient materials since the problems of environment and energy are major threshold areas. The development of new materials is growing day by day to replace the conventional materials in aerospace, marine engineering, automobile engineering industries etc., Hence, composite materials are found to be an alternative. A variety of metals and their alloys such as Aluminum, Magnesium and Titanium are comprehensively used as matrix materials. Among these Aluminium alloys have been used extensively, because of their excellent strength, low density, corrosion resistance and toughness. Similarly, many researchers have attempted to develop aluminum based metal matrix composites using different reinforcements such as SiC, Al2O3, B4C, TiC, TiO2, B4C etc., are added to the matrix to get required MMC’s. Among these reinforcements, B4C emerged as an exceptional reinforcement due to its high strength to density ratio, possesses high hardness and avoid the formation of interfacial reaction products with aluminum. Hence, in this paper attempts are made to fabricate Al 6061-3, 6, 9 and 12 wt.% B4C metal matrix composites by stir casting process to study fatigue life and fracture toughness as per ASTM standards. It is evident that fatigue strength and fracture toughness of the composites were enhanced with the addition of the wt.% of the reinforcement.

Preparation of RBSC Green Bodies by Gel-Casting

2008 ◽  
Vol 368-372 ◽  
pp. 834-836
Author(s):  
Hai Lin Liu ◽  
Yu Feng Chen ◽  
Hua Wang ◽  
Jie Tang
Keyword(s):  
Silicon Carbide ◽  
Flexural Strength ◽  
Monomer Concentration ◽  
Casting Process ◽  
Green Body ◽  
Carbon Particles ◽  
Gel Casting ◽  
Monomer Content ◽  
Silicon Carbide Particles ◽  
Carbide Particles

In this paper, green bodies of RBSC were prepared through the gel-casting process. The effects of monomer concentration and ratio of MBAM to AM on the strength and microstructure of the green bodies were studied. When the monomer content increased from 10wt% to 20wt %( relative to water in the slurry), the flexural strength increases efficiency. However, the flexural strength decreases when the monomer content was above 20wt%. Similarly, when the ratio of MBAM to AM increased from 1/19 to 1/9, it had the same effects on the flexural strength of green bodies. It was found that silicon carbide particles were packaged by the carbon particles with gel. When the monomer content was 20wt% and the ratio of MBAM to AM was 1/9, the green body showed the best homogeneous microstructures and its flexural strength achieved 8MPa.

Influence of Fabricated Process on Mechanical Properties of Porous SiC-Particle/Si3N4 Composites

2007 ◽  
Vol 336-338 ◽  
pp. 1320-1323 ◽  
Author(s):  
Hong Jie Wang ◽  
Wen Zhang ◽  
Yu Bai ◽  
Guan Jun Qiao ◽  
Ji Qiang Gao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Flexural Strength ◽  
Powder Compact ◽  
High Strength ◽  
Uniform Structure ◽  
High Porosity ◽  
Gel Casting ◽  
N2 Atmosphere ◽  
Porous Sic ◽  
Sic Particle

In this paper, the mechanical properties of porous Si3N4/SiC composite prepared by different forming method (uniaxial pressing and gel-casting) were compared. Using gelcasting and two steps sintering technology, the porous SiC-particle/Si3N4 composites with a high strength, uniform structure and a relative high porosity were obtained by adding a little amount of nano carbon in slurry. The flexural strength of optimized material reaches to 100MPa and its porosity is more than 60%. But using uniaxial pressing and sintering at N2 atmosphere, because the green bodies have the high density, and the density distribution of a powder compact was not uniform, the flexural strength is not high, and at the same time, the microstructure is not uniform also.

scholarly journals A Finite Element Analysis for Improvement of Shaping Process of Complex-Shaped Large-Size Silicon Carbide Mirrors

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4136
Author(s):  
Ling Qiao ◽  
Jingchuan Zhu ◽  
Yingnan Wan ◽  
Congcong Cui ◽  
Ge Zhang
Keyword(s):  
Silicon Carbide ◽  
Finite Element ◽  
Structural Integrity ◽  
Casting Process ◽  
Green Body ◽  
Technological Parameters ◽  
Element Analysis ◽  
Gel Casting ◽  
Generation Mechanisms

In the gel-casting process, the proper selection of technological parameters is crucial for the final quality of a green body. In this work, the finite element method is used to investigate the mold characteristics in the gel-casting process, and the typical flow behaviors under different conditions are presented. Based on the distribution characteristics of temperature, pressure and flow field of gel polymer, the simulated results provide some possible reasons for the generation mechanisms of defects. Then, a series of simulations were performed to investigate the effect of process parameters on the molding quality of green gel-cast bodies. The results show that the decreasing loading speed can effectively reduce the number of defects and improve the molding quality. In addition, this paper presents a new technique by applying the exhaust hole to decrease the number of defects and, hence, improve structural integrity. The influence of the loading speed on the mold characteristics is well understood for the gating system with an exhaust hole, which suggests to us appropriate parameters for optimizing the molding design. This work provides a theoretical basis to explicate the generating mechanism of defects involved in the gel-casting process and acquires an optimized technique to produce a silicon carbide green body.

BERYLCO NICKEL ALLOY 440

Alloy Digest ◽  
1975 ◽  
Vol 24 (9) ◽  
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Nickel Alloy ◽  
High Strength ◽  
Heat Treating ◽  
Electronic Components ◽  
High Temperature Mechanical Properties ◽  
Temperature Performance ◽  
Solution Treated ◽  
Complex Shapes

Abstract BERYLCO NICKEL ALLOY 440 is an age-hardenable nickel-beryllium-titanium alloy that offers high strength, excellent spring properties outstanding formability, good high-temperature mechanical properties, and resistance to corrosion and fatigue. Complex shapes can be produced in the solution-treated (soft) condition and then aged to a minimum tensile strength of 215,500 psi. It is used for mechanical and electrical/electronic components in the temperature range -320 to 800 F. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-94. Producer or source: Kawecki Berylco Industries Inc.. Originally published September 1964, revised September 1975.

AMPCO 483

Alloy Digest ◽  
1978 ◽  
Vol 27 (4) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Physical Properties ◽  
Tensile Properties ◽  
Base Alloy ◽  
High Hardness ◽  
High Strength ◽  
Heat Treating ◽  
Good Resistance ◽  
Copper Base ◽  
Copper Base Alloy

Abstract AMPCO 483 is a copper-base alloy that can be used in the cast or wrought form. It provides high strength, high hardness, excellent resistance to corrosion and good resistance to fatigue and wear. It is well suited for service at temperatures up to 750 F and for applications such as pickling equipment, nuts and marine hardware. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, forming, heat treating, machining, and joining. Filing Code: Cu-352. Producer or source: Ampco Metal Inc..

Research on High-Speed Cutting of Cr12MoV Hardened Steel - A Review

2020 ◽  
Vol 15 ◽  
Author(s):  
Fei Sun ◽  
Guohe Li ◽  
Qi Zhang ◽  
Meng Liu
Keyword(s):  
High Speed ◽  
Cutting Temperature ◽  
High Hardness ◽  
High Strength ◽  
Hardened Steel ◽  
Parameters Optimization ◽  
Future Research ◽  
High Speed Machining ◽  
Machined Surface ◽  
Stamping Die

: Cr12MoV hardened steel is widely used in the manufacturing of stamping die because of its high strength, high hardness, and good wear resistance. As a kind of mainstream cutting technology, high-speed machining has been applied in the machining of Cr12MoV hardened steel. Based on the review of a large number of literature, the development of high-speed machining of Cr12MoV hardened steel was summarized, including the research status of the saw-tooth chip, cutting force, cutting temperature, tool wear, machined surface quality, and parameters optimization. The problems that exist in the current research were discussed and the directions of future research were pointed out. It can promote the development of high-speed machining of Cr12MoV hardened steel.

scholarly journals Effect of weld metal composition on impact toughness properties of shielded metal arc welded ultra-high hard armor steel joints

2020 ◽  
Vol 29 (1) ◽  
pp. 186-194
Author(s):  
V. Balaguru ◽  
Visvalingam Balasubramanian ◽  
P. Sivakumar
Keyword(s):  
Impact Toughness ◽  
Weld Metal ◽  
Welded Joints ◽  
Weight Ratio ◽  
High Hardness ◽  
High Strength ◽  
Solidification Mode ◽  
Austenitic Phase ◽  
Ferrite Number ◽  
Steel Joints

AbstractNowadays, ultra-high hard armor (UHA) steels are employed in armor tracked vehicle (ATV) construction because of their high hardness, high strength to weight ratio, and excellent toughness. UHA steels are usually welded using austenitic stainless steel (ASS) welding consumables, to avoid hydrogen-induced cracking (HIC). The use of ASS consumables to weld the above steel was the only available remedy because of higher solubility of hydrogen in the austenitic phase. In this investigation, an attempt was made to investigate the effect of ASS consumables (with different Creq/Nieq ratio) on solidification mode, impact toughness and microstructural characteristics of shielded metal arc (SMA) welded UHA steel joints. The welded joints were characterised based on impact toughness properties, hardness, and microstructural features. As the ferrite number increases with an increase in Creq/Nieq ratio result in different solidification mode (A, FA, F). It is also found that ferrite number of weld metal has appreciable influence on impact toughness and has inversely proportional relationship with impact toughness of the welded joints.

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