材料概论 双语 第三章ppt

Power Pressing
l powder pressing the ceramic analogue to powder metallurgy,is used to fabricate both clay and nonclay compositions including electronic and magnetic ceramics as well as some refractory brick products
the changs take place during drying and firing processes , the characteristics of the finished piece and the proportions of the constituents: clay Fra Baidu bibliotekuartz(石英) and flux （助熔剂）.
The classification of ceramic
Traditional ceramics
Traditional ceramics are derived and processed from clay or nonclay minerals.
Traditional ceramics are usually heavy,fragile( 脆)
3.2 Nature of ceramics
properties extreme hardness, heat resistance corrosion resistance, low ductility low electrical and thermal conductivity apply ceramic heat engine, batteries, computer and communication technologies, hunman bone
3.2.1 porosity and density atomic weight
factors of density atoms stack（堆叠） reduce the strength porosity （多孔性 ） increase the insulating（绝热 性） makes lighter
（2）. Henan Ware: It’s primitive decoration. Han Ware : Slip decoration was devised , as were colored glazes.
Sung Ware : A superb gray stoneware covered in white slip and decorated with incised or painted flowers.
Firing
After drying , a body is usually at a
temperature between 900 the 1400:firing temperature depends on the composition and desired properties of the finished piece.
Nuclear Fuels
The History of Chinese Ceramics
（1）. 3 000 B.C : Potters in Henan and Gansu is technically superior.
After 600 A.D : Ceramics is adaptable to higher firing temperatures and more translucent and white after firing.
Classification based on applications
Advanced (New) Ceramic materials Oxides Abrasives Bioceramics Electrical Gas Turbiness Cutting Tools (Steel) Nitrides Rocket Engines Carbides Abrasives Resistance Heating Steel Additives
Classification based on applications
Advanced ceramics
Advanced ceramics are developed form rather simple chemical compounds , and advances in processing which have provided greater control over their structures. Advanced ceramic: the scale of the raw materials and microstructures, including the crystal grains, crystal interface, pores and defects is at the level of microns.
Eighteenth-and nineteenth-Century Ware: Europeans discovered the secret of Chinese ceramic . their commercial incursions into china created such political unrest. China ceramic industry is very depressed.
melting pot as the main sintering tool
Performance:high strength、high
hardness 、 corrosion resistance(耐腐蚀) electric conduction、 BC(biocompatibility) （生物相容性）and so on.
Cutting Tools
Refractory Brick Glass Additives High Temperatures Substrates Cutting Tools(cermets) For IC Chips coatings Armor Ceramic Matrix Composites Reinforcing Fibers
The development of ceramics
（1）. human-made ceramics can be date back to at least 24,000 BC. and Appearance simple, Raw material simple, processed simple. It is utilitarian . （2）. 9 000 BC functional pottery beginning to be appearing. （3）. Now ceramics rapid development.
Hydropalsdtic Forming
The most common hydropalstic forming technique is
extrusion , in which a stiff plastic ceramic mass is forced through a die orifice having the desired crosssectional geometry
Drying
as drying progresses and water is removed,the
interparticle separation decreases,which is manifested as shrinkage during drying it is critical to control the rate of water removal
Slip Casting
a slip is a suspension of clay and other nonplastic
materials when poured into a porous mold ,water from the slip is absorbed into the mold,leaving behind a solid layer on the mold wall the thickness of which depends on the time
Advanced Ceramic Processing
Chemical Processes Melt Processing Producing Single-crystal Materials Vapor Processing Directed Metal Oxygen Process
Preparation procedure:No longer with
3.2.2structure of ceramics
the silicate structure is SiO4 tetrahedra linked by ionic and covalent (共价） compounds different silicates depend on different SiO4 tetrahedra(such as :mica（云母） and soapstone（滑石）)
小组成员 : 李志鹏 李萌萌 李 梦龙 李建毅 张良玉 李连成
introduction
1. What is the ceramic
2. The development of ceramics 3. Traditional ceramics 4. Advanced ceramics
5. The History of Chinese Ceramics
3.3 Ceramic Processing
Traditional processing Advanced Ceramic Processing
Traditional Processing
Structural clay products and whitewares
Forming
Drying and Firing Power Pressing Hydroplastic Forming Slip Casting
What is the ceramic
The word “ceramic” can be traced back to Greek term “keramos” which is related to an old Sanskrit root meaning “to burn”. Can be defined as inorganic compounds made by heating clay or other mineral matter to a high temperature at which they partially melt and bond together. Ceramic can be defined as inorganic, nonmetallic materials.
Ming ware : In one ware ,they superimposed their preceded glazing and Persian colored glazes On one another and fired at low temperature. brilliant red glazes were similarly applied.
Solid phase method:Including thermal
decomposition method(热分解法) ； Amorphous alloy annealing crystallization method（非晶合金退火结晶法）；SHS(自 蔓延高温合成)