BN 氮化硼的简介.ppt

Boron Nitride Name: Students number: Supervisor: Outline Boron Nitride- Slide 2 of 16 Introduction Properties Production process Application Prospect Introduction--Definition Boron Nitride- Slide 3 of 16 Definition: a covalent semiconductor materical consisited of element B in ⅢA and element N in ⅤA. Chemical composition: B 43.6% N 56.4% Molecular formula: BN Crystal form: 1.HBN 2.CBN 3.RBN 4.WBN Introduction--History Boron Nitride- Slide 4 of 16 BN ceramic 1.In 1842 BN ceramic. 2.In 1957 R.H.wentrol CBN 3.In 1973 The US CBN blade CBN blade 4.In 1979 Sokolowsk pluse（Plasma technology） CBN film 5.At the end of 1990s PVD CVD CBN film Properties--Physical Boron Nitride- Slide 5 of 16 CBN: (1) black ,brown or dark red crystal (2) sphalerite structure (3) good thermal conductivity (4) high hardness ,is second only to diamond (5) used for cutting tools and abrasives Properties--Physical Boron Nitride- Slide 6 of 16 HBN: (1) a very low coefficient of friction (2) good high temperature stability (3) good thermal shock resistance (4) high strength (5) high thermal conductivity (6) low expansion coefficient (7) microwave or infrared Properties--Chemical Boron Nitride- Slide 7 of 16 1.resistance to chemical attack (inorganic acid and water) 2. In the hot concentrated alkali, the boron nitrogen bond is broken 3.Oxidized by air above 1200℃. its melting point is 3000. 4.Slightly soluble in hot acid 5.insoluble in cold water BN Production process Boron Nitride- Slide 8 of 16 Graphite boron nitride Graphite (HBN) Cubic boron nitride Diamond 1800℃ 8Gpa 5.5Gpa 1500℃ Fe Ni etc. Application Boron Nitride- Slide 9 of 16 1.High temperature solid lubricant 2.suppress various BN products for doing parts of high temperature, high pressure, insulation, c