Date post: | 11-Aug-2015 |
Category: |
Engineering |
Upload: | shubham-shukla |
View: | 190 times |
Download: | 2 times |
CERAMICS & CERAMIC INDUSTRIES
An Overview
Table of Content Ceramics
Structure of Ceramics
Traditional vs. Advanced Ceramics
General Characteristics & Application
The Future
Production Process
Ceramic Industries
Global Trade Profile
India’s Trade Profile and Market Access
Significant Environmental aspects and impacts
Ceramic with Adhesives and Paints
Ceramics Ceramics can be defined as solid compounds that are formed by the
application of heat, and sometimes heat and pressure, comprising at least two elements provided one of them is a non-metal or a nonmetallic elemental solid. The other element(s) may be a metal(s) or another non metallic elemental solid(s).
In other words, what is neither a metal, a semiconductor or a polymer, is a Ceramic.
The word ‘Ceramic’ is derived from a Greek word ‘Keramos’ which means ‘burnt earth’ or ‘pottery’.
Structure of Ceramics
Solids or Ceramics can be classified as crystalline solids, or amorphous, glassy, or non crystalline solids.
The unit cells combine to give crystal systems, with 14 possible arrangements-Bravais lattices.
A polycrystalline solid is comprised of a collection of many single crystals, termed grains, separated from one another by areas of disorder known as grain boundaries.
Traditional versus Advanced Ceramics
General Characteristics & ApplicationsPropertyThermal Insulation Refractoriness Thermal conductivityElectrical and dielectric Conductivity Ferro electricity Low-voltage insulators Insulators in electronic Insulators in hostile
cond. Ion-conducting Semi conducting Non linear I-V Gas-sensitive
conductionMagnetic and super conductive Hard magnets Soft magnets Super conductivity
Applications
High-temperature furnace linings insulator Furnace linings, containment of melts Heat sinks for electronic packages
Heating elements for furnaces Capacitors (Ba-titanate-based materials) Insulation (porcelain, steatite, forsterite) Substrates for electronic/ical packaging
insulators Spark plugs (Al2O3) Sensor and fuel cells (ZrO2,A12O3,etc.) Thermistors and heating elements Current surge protectors (Bi-doped ZnO, SiC) Gas sensors (SnO2, ZnO)
Ferrite magnets[(Ba,Sr)O6Fe2O3] Transformer cores[(Zn,M)Fe2O3,]; magnetic
tapes Wires and SQUID
magnetometers(YBa2Cu3O7)
PropertyOptical Transparency Translucency and
chemical inertness Non linearity IR transparencyNuclear applications Fission FusionChemical Catalysis Anticorrosion Bio compatibilityMechanical Hardness High-temp strength
retention Wear resistance
Applications
Windows, cables for optical communication Heat-and corrosion-resistant materials, for Na lamps
Switching devices for optical computing(LiNbO3) Infrared laser windows (CaF2, SrF2, NaCl)
Nuclear fuel, fuel cladding (C,SiC),neutron moderators Tritium breeder materials, fusion reactor lining
Filters(zeolites);purification of exhaust gases Heat exchangers, chemical equipment in corrosion Artificial joint prostheses (Al2O3)
Cutting tools (SiC whisker-reinforced A12O3, Si3N4) Stators and turbine blades, ceramic engines (Si3N4)
Bearings(Si3N4)
The Future Ceramics are simultaneously our oldest and newest solids. Traditional
ceramics have served humanity well for at least the past 10 millennia.
CERAMIC INDUSTRIES The ceramic industry has a long history, pottery vessels and clay
bricks being used for storing water and food, being thought to be around since 9,000 or 10,000 BC.
Global Trade Profile
During the period from 2007 to 2014, total ceramics trade grew at a CAGR of 9.8%, from US$ 79.6 billion to US$ 123.5 billion.
Major Exporters China was the largest ceramic exporter during 2014, with exports of US$ 13 billion. Italy,
Germany and Spain followed China with annual exports of US$ 11.3 billion, US$ 9.2 billion and US$ 8.9 billion, respectively. The top ten countries together accounted for close to 72% of total ceramics exports during 2014.
Major Importers United States was the world’s largest ceramic importer during 2014, with imports worth US$
9.4 billion. US is followed by France, Germany and United Kingdom with annual imports of US$ 6.7 billion, US$ 6.6 billion and US$ 6.0 billion, respectively.
India’s Trade Profile and Market Access The Indian Ceramic Industry ranks at 7th position in the world and
produces around 3.7% of global output.
The industry provides employment to 850,000 people, of whom 80,000 are directly employed.
Gujarat accounts for around 70 % of total ceramic production.
During 2014, India was the 13th largest ceramic trading nation in the world and accounted for a share of around 1.9% in total ceramics trade.
During the period, from 2007 to 2014, India’s ceramics trade increased from US$ 543 million to US$ 1138 million at a CAGR of 22.2%.
The increase in trade was led by rise in imports, which increased, from US$ 452.9 million in 2007 to US$ 918.8 million in 2014, at a CAGR of 30.9%.
India’s ceramic exports on the other hand increased at a CAGR of 12.8%, from US$ 479.3 million to US$ 607.5 million.
China was India’s main source of ceramics imports, China alone accounted for 60.7% of India’s ceramic imports.
Significant Environmental aspects and impacts
Environmental aspects
Wastewater
Energy
Water Production Gaseous emission (drying, firing)
Raw materials f or ceramic body of Emission to air: dust
Packaging materials Ceramic Noise
Auxiliary materials Materials Solid Wastes
Frit, Pigment and materials f or glazes Waste Heat
Wastes
Traffic and Transport
Ceramic Products
Ceramic with Adhesives and Paints Ceramic Polymer coating for drinking water applications:
Restoration of pipework according to Promotec-system
The Ceramic Polymer GmbH produces high-performance coatings with integrated micro ceramic particles for different fields of application. The properties of the ceramic – chemical resistance, abrasion resistance and weathering stability – justify the high quality of coating systems.
(3-AMINOPROPYL)TRIMETHOXYSILANE OR 3-
(TRIMETHOXYSILYL)PROPYLAMINE [APTMS] CAN BE USED AS ADHESIVE FOR A METAL-CERAMIC SURFACE
Mineral components like Mica, glass and metal oxide surfaces can all be silanized, because they contain hydroxyl groups which attack and displace the alkoxy groups on the silane thus forming a covalent -Si-O-Si- bond. The goal of silanization is to form bonds across the interface between mineral components and organic components present in paints, adhesives, etc. Silanization (or siliconization) of glassware increases its hydrophobicity and is used in cell culturing to reduce adherence of cells to flask walls.
NANOFILLERS ‐IMPROVING PERFORMANCE AND REDUCING COST
Fillers are mainly utilized to reduce the consumption of expensive binder material and to improve the physical properties of the resulting composite material. They are widely used in paper, rubber, plastics, adhesives & sealants, paints & coatings, and also in concrete.
Particle Size
The filler particle size determines the “inner” or specific surface area which is the potential contact area between filler material and surrounding binder matrix. Fully exfoliated and perfectly dispersed nanofiller will have the greatest effect on the physical properties.
Geometry
Elongated nanostructures such as carbon nanotubes exhibit high aspect ratios increasing the reinforcing ability on the surrounding matrix material. Nanotubes can be considered as (quasi‐)one‐dimensional filler particles in terms of reinforcement. Similar nano‐materials are nanowhiskers, nanorods, nanowires and nanofibres which have also been reported as nanoscopic reinforcing filler material for polymers.
Summary
Nanofillers are characterized by their particle size, specific surface area, particle geometry and chemical functionalisation.
Smaller filler particle sizes provide new functionalities such as improved mechanical strength and control of rheological properties.
The high specific surface area of nanomaterials provides a route towards novel properties and decreased filling levels.
Needle‐like nanofillers have a stronger impact on the mechanical properties.
Hybrid materials provide a route towards fully dispersed nanomaterials and superior nanocomposites.
Critical issues are exfoliation and dispersion of nanomaterials, and a poorer processability.
Thank You!