Study on Microstructures and Properties of Porous TiC Ceramics Fabricated by Powder Metallurgy
- PDF / 2,908,545 Bytes
- 8 Pages / 593.972 x 792 pts Page_size
- 42 Downloads / 196 Views
JMEPEG DOI: 10.1007/s11665-016-2472-y
Study on Microstructures and Properties of Porous TiC Ceramics Fabricated by Powder Metallurgy Yana Ma, Chonggao Bao, Longhao Han, and Jie Chen (Submitted February 12, 2016; in revised form October 18, 2016) Powder metallurgy process was used to fabricate porous titanium carbide (TiC) ceramics, in which TiC powders were taken as the raw materials, nickel was used as the metallic binder and urea was the spaceholder. Microstructure, composition and phase of porous TiC ceramics were characterized by scanning electron microscopy (SEM) and x-ray diffraction (XRD). Flexure strength of the porous TiC ceramics was tested by a three-point bending method. The results show that macropores and micropores coexist in the prepared porous TiC ceramics. Moreover, the pore number, size and distribution in porous TiC ceramics can be controlled on demand. Particularly, the factors such as the number or size of space-holder, compacting pressure and Ni content have significant effect on the porosity and flexure strength. Keywords
microstructures, porous ceramic, powder metallurgy, properties, space-holder, titanium carbide
1. Introduction Porous ceramics contain high volume fraction of porosity and possess attractive properties, such as low weight, high specific surface area, high permeability and high adsorption (Ref 1). Therefore, they have been applied in industrial and engineering fields, including fuel cell electrodes (Ref 2), filters (Ref 3), absorbers (Ref 4), catalyst carriers (Ref 5), surgical implants (Ref 6) and reactors (Ref 7). Titanium carbide (TiC) is a typical transition metal carbide. Due to the coexistence of the ionic bond, covalent bond and metal bond, TiC simultaneously possesses characteristics of good thermal stability, high wear resistance and electrical conductivity (Ref 8, 9), etc. Porous TiC ceramics have already been used in ceramic-metal composites (Ref 10), water purifying (Ref 11) and catalyst supports for chemical or biochemical reactions (Ref 12, 13). Until now, only a few reports about the preparation of porous TiC ceramics have been done. Nangrejo (Ref 14) used the silicon carbide precursor mixed with TiC powder to form a polysilane solution and, then, employed polyurethane foams as the template to dip in the solution. Finally, the obtained foams were sintered to produce the SiC-TiC porous ceramic at 11001600 °C in a nitrogen atmosphere. Sun (Ref 15, 16) prepared a wood-like structure porous TiC ceramic with wood templates through tetrabutyl titanate vacuum infiltration. Popovska (Ref 17) used carbonized paper as the porous templates by adopting chemical vapor infiltration to produce biomorphic porous TiC ceramic. Shi (Ref 18) fabricated porous TiC ceramics by the coat-mix process with titania powders as the titanium source and phenolic resin as the carbon source. Kobashi (Ref 19)
Yana Ma, Chonggao Bao, Longhao Han, and Jie Chen, State Key Laboratory for Mechanical Behavior of Materials, XiÕan Jiaotong University, XiÕan 710049, China. Contact e-mail: [email protected]
Data Loading...
