1、LOGOCeramic Materials School of materials science and engineeringCompany name21 Introduction1.1 what is Ceramics?A product obtained through the action of fire upon earthy materialsInorganic, nonmetallic solids, usually oxides, nitrides, or carbides. Ceramics are typically crystalline in nature and a
2、re compounds formed between metallic and non-metallic elements.Company name31.2 Typical propertiesl Moderate density l Low electrical conductivity insulators l Strong compressive strength tensile strength l Low - moderate thermal conductivity insulators l Brittle l Hard Very high hardnessl raw mater
3、ials are plentiful and inexpensivel many ceramics transparent to lightl translucent, or opaquel High elastic modulus - greater than metalsl Excellent wear resistance because of high compressive strength and hardnessl Good resistance to chemical attackCompany name4Main limitation: very brittle and th
4、ey are flaw sensitive Cracks and other flaws are always presentCompany name51.3 Classification advanced ceramics also known as engineering or technical ceramics, refer to materials which exhibit superior mechanical properties, corrosion/oxidation resistance, and thermal, electrical, optical or magne
5、tic properties. Company name6Company name7Company name82 Nature of CeramicsCompany name92.1 Porosity and DensityCompany name10Company name11Company name122.2 Structure of CeramicsCrystal phase, glass phase, poreCompany name13Company name143 Ceramic ProcessingCompany name15Chemical Processes: Sol-gel
6、 processingsolid-phase sinteringliquid-phase sinteringmechanical processingPhysical vapor deposition(PVD)Chemical vapor deposition(CVD)Company name16Company name17vA common technique for consolidating ceramic powdersAtomic diffusion mass transfer(particles to open spaces) tremendous amount of shrink
7、age cracking, distortion &/or residual stressesReaction formed nonoxide ceramicsSintering of ceramic powdersCompany name18Properties of CeramicsCompany name19Company name20Mechanical properties Company name21Strong: high compressive strength HardInelastic: do not bend like metalshigh elastic modulus
8、Fracture toughness: depends on the geometry of both the object and the crack, the applied stress, and the length of the crackChemical property: durable (resistant to corrosion)Physical properties: low density and high melting point structural applications Weakness: brittle compositesto improve the t
9、oughnessCompany name22Applications of CeramicsCompany name23Company name24GlassesnA glass (amorphous material) is quite different from a crystalline metal or ceramic. In a glass, there is no long-range crystalline order.Glass transitionnThe temperature above which the glass becomes soft and viscous
10、enough to work is related to the glass transition temperature, Tg.nBelow the glass transition temperature, the material is relatively hard and stiff; above it, it becomes more viscous.Company name25Company name26Company name27Company name28Company name29Company name3031写在最后写在最后成功的基础在于好的学习习惯成功的基础在于好的学习习惯The foundation of success lies in good habits32谢谢大家荣幸这一路，与你同行ItS An Honor To Walk With You All The Way讲师：XXXXXX XX年XX月XX日
