Spheroid Growth during Sintering of Copper Coated Silicon Carbide Particles in the Fabrication of Nanocomposite

2007 ◽  
Vol 280-283 ◽  
pp. 1275-1278 ◽  
Author(s):  
Rui Zhang ◽  
Hai Long Wang ◽  
Lian Gao ◽  
Shao Kang Guan ◽  
Jing Kun Guo

Copper coated silicon carbide clusters were used to fabricate nanocomposite. Compacts were isostatically pressed and heated in nitrogen atmosphere. Microstructure observations were carried out to show the spheroid growth of the coated clusters. Spheroid growth was found to proceed through coalescence of smaller spheroids of the coated Cu/SiC composite particles. The densification process contains steps of agglomeration – kernel-shell formation – slumping movement. Grain growth of the adherent Cu particles is suppressed due to the constraint of rigid SiC particles. This is the deterministic characteristic of the coated composite particles.

Author(s):  
MADEVA NAGARAL ◽  
Murali Mohan R ◽  
V Auradi ◽  
Bharath V

In the current exploration, the impact of the 100 to 125 micron size addition of silicon carbide (SiC) on the mechanical performance of Al6061 alloy has been studied. The Al6061 alloy dispersed with 6, 9, and 12 wt.% of SiC particles were synthesized by a two-step stir cast route. Two-step addition of the preheated particles into the melt helps avoid the agglomeration of the particles, which further contributes to enhancing the properties of composites. The orchestrated composites were exposed to microstructural examines and mechanical properties evaluation. Microstructural portrayals of acquired examples were completed by SEM microscopy, EDS, and XRD patterns. The event of SiC particles were affirmed by the XRD patterns. The density of the Al6061-SiC composites was increased with the addition of high-density silicon carbide particles. The hardness, ultimate, and yield qualities of metal composites have been improved with the increase in the content of SiC support. The ductility of SiC reinforced composites decreased with hard ceramic particles' incorporation in the Al matrix alloy. Various fracture mechanisms were observed in the Al6061-SiC composites using SEM.


2012 ◽  
Vol 512-515 ◽  
pp. 951-954
Author(s):  
Bing Bing Fan ◽  
Huan Huan Guo ◽  
Jian Li ◽  
Hai Long Wang ◽  
Ke Bao ◽  
...  

The SiC/Cu composite is one of the "structural-functional" materials. It shows good mechanical properties and very high thermal, high electrical conductivity etc. But the co-dispersion, wetting and bonding between SiC and Cu interface are of practical importance in the preparation of SiC/Cu composites. In this work, surface treatment techniques such as high-temperature oxidation, acid dipping and alkaline wash were adopted separately on silicon carbide particles, in order to improve the wettability and physical and chemical compatibility between silicon carbide and copper, then we used the replacement reaction method and decomposition-reduction reaction method to generate Cu coating on the surface of silicon carbide. The results shown that, the surface of silicon carbide particle which treated by alkaline wash was cleaner and more rough than that only treated by high-temperture oxidation, moreover, the specific surface of the particle was increased, which resulted in a compact layer of Cu coating. for the same silicon carbide particles, the effect of the Cu coating prepared by decomposition reaction method was better than that by reduction reaction method.


2021 ◽  
Vol 1035 ◽  
pp. 768-772
Author(s):  
Jing Kun Li ◽  
Xue Ping Ren ◽  
Qiang Yan ◽  
Yan Ling Zhang ◽  
Hong Liang Hou

Porous silicon carbide was sintered at 1300 °C/30 MPa for 2 h with 4 wt.% magnesium alloy and 4 wt.% chromium carbide composite additives. The sintered ceramic presented density of around 92% of the theoretical density. No new phase was observed after sintering. Mg segregates around chromium carbide particles in sintered ceramic. The silicon carbide particles were mainly bonded by melt magnesium alloy and chromium carbide diffused in solid state. The voids existed in the sintered ceramic, but much more fracture occurred in silicon carbide particles during bending due to high bonding strength of sintering necks. Some voids existed in the ceramic, which act as crack sources during fracture.


2019 ◽  
Vol 116 (6) ◽  
pp. 631 ◽  
Author(s):  
R. Ashok kumar ◽  
G.R. Raghav ◽  
K.J. Nagarajan ◽  
Sathish Rengarajan ◽  
P. Suganthi ◽  
...  

The main objective of this work is to modify the mechanical as well as surface properties of weld nugget by the reinforcement of hybrid ceramic particles (alumina and silicon carbide). This is accomplished by combining friction stir welding (FSW) and friction stir processing (FSP) on dissimilar AA6101-T6 and AA1350 aluminium alloys. For this purpose, various levels of mixing proportions of Al2O3 & SiC particles are used with constant groove depth and width i.e. constant groove dimension. To evaluate the quality of joints, tensile, bending, micro-hardness, wear and microstructural studies are carried out. Among these, reinforcement of 100% alumina particles exhibits better mechanical and wear properties. On the other hand, reinforcement of 100% silicon carbide particles produces poor mechanical and wear properties. And also increment in percentage of reinforcement of alumina particles improves the mechanical and wear properties of weld nugget, when compared to increment in percentage of reinforcement of silicon carbide particles.


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