Alumina结构的陶瓷

Properties of alumina ceramics Item test condition Unit and Symbolic Corundum -mullitep orcelain A3S2-2 A-75 A-95 A-96 A-99 volume density G/cm3 ≥2.80≥3.20≥3.60≥3.70≥3.70Air tightness ——passpasspassLiquid permeability passpasspasspasspassFlexural strength Mpa≥100≥200≥280≥280≥300linear expansion coefficient 20 100°C×10-6/°C≤8≤6———20 500°C×10-6/°C——6.5 7.56.5 7.56.5 7.520 800°C×10-6/°C——6.5 86.5 86.5 8Flexural strength 1MHz 20°C≤≤9 109 109 10.5500°C——9 109 10—10GHz20°C——9 109 109 10.5the tangent of its dielectric loss angle 1MHz 20°C×10-4≤20≤10≤4≤4≤2.5500°C×10-4——30 4030 40—10GHz20°C×10-4——≤10≤10≤6Volume resistivity 100°CΩ.cm≥1012≥1012≥1013≥1013≥1013300°CΩ.cm——≥1010≥1010≥1010500°CΩ.cm——≥108≥108≥109Thermal shock resistance ——passpasspassBreakdown Strength kV/mm≥15≥20≥18≥15≥15Chemical stability 1:9HCImg/cm2——≤7.0≤7.0≤0.710%NaOHmg/cm2——≤0.2≤0.2≤0.1grain Size μm——15 30——application Mainly usedfor large device porcelainused for Highmechanicalstrengthdeviceor partshell and electronic substrateCausing coldness substrateshell and electronic substrate