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What’s Is Machinable Glass Ceramic?

Machinable Glass Ceramic is a mica glass ceramic material with a unique combination of properties. It is easily machinable using conventional metalworking tools, with no post-firing required. A versatile ceramic material with technical strength and insulation properties exceeding high-performance plastics, it is also stable in high temperatures (continuous at 800° Celsius, up to a peak of 1,000° Celsius) with 0.0069% porosity. The ceramic material also acts as an electrical insulator that is radiation resistant and has low thermal conductivity.

Machinable Glass Ceramic

Characteristics include:

1.0.0069% porosity and non-shrinking

High dielectric strength
Electrical resistivity
Withstands high temperatures up to 800ºC
Tight tolerance capability
Easily and economically machined into complex shapes and precision parts

Applications include:

Feedthroughs
Hermetic seals
Insulators and supports for vacuum environment feed-throughs

Spacers, headers, and windows for microwave tube devices

Aerospace components
Welding nozzles

7. Fixtures

BN-TiB2 Boron Nitride Ceramic Crucible for High Power of Electron Beam

BN-TiB2 crucible is often used for electronic beam evaporation. The material is with electric conduction.

Technical Data:

Material: BN+TiB2

Binder: B2O3

Color: Grey

Electrical resistivity(room temperature): 300-2000uΩ.cm

Working temperature: ＜1800℃

Thermal Conductivity: ＞40 W/mK

Coefficient of thermal expansion:4-6×10^-6K

Bending Strength: ＞130Mpa

Evaporation Rate: 0.35-0.5 g/min.cm2

BN-TiB2 Boron Nitride Ceramic Crucible for High Power of Electron Beam

Types of oxygen sensors

According to the substance used in their sensitive element, are:

Zirconium (zirconium oxide)

Titanium (titanium oxide)

Wideband

According to their design:

Single-wire lambda sensor

Two-wire lambda sensor

Three-wire lambda sensor

Four-wire lambda sensor

Single-wire lambda sensor was used in the early injection systems with feedback (lambda regulation). It has only one terminal, which is the signal terminal. Sensor ground is its housing and it connects to the engine ground through the exhaust pipes.

Two-wire lambda sensor has a separate grounding cable. It was used in the early injection systems with feedback (lambda regulation) also.

The disadvantage of the single-wire and the two-wire sensors is that their operating temperature range starts at 300 ºC. The sensor will not work and will not produce a signal until this temperature is reached. It was necessary for the sensor to be mounted as close to the engine cylinders as possible in order to heat and wrap from the hottest exhaust gas stream. The process of heating the sensor slows down the regulation process of the onboard controller because of the feedback. In addition, using the exhaust pipe as a signal ground requires the sensor’s thread to be coated with a special electrically conductive paste, which increases the possibility of a bad contact in the feedback circuit.

Types of oxygen sensors

In the three-wire lambda sensors, is a special heating element inside which is constantly turned on when the engine is working and thus it’s reducing the heating time of the sensor to the working temperature. This allows the installation of the sensor on the exhaust manifold, near the catalytic converter. The disadvantage is the need for electrically conductive grease.

In the four-wire oxygen sensors – two of the terminals are the heater terminals and the other two, are the signal termina

If you want to know more, pls contact us.

What Is Ceramic Heat Sink?

Components of modern technology products, such as computer chips or light-emitting diodes, generate more and more waste heat during operation, and generally existing heat dissipation devices used to assist heat dissipation components usually include at least a metal heat sink and a The fan conducts the waste heat from the operation of the heating element through the heat sink to remove it by air convection, and uses the fan to forcibly accelerate the convection of the air around the heating element to achieve the effect of rapid heat removal.
However, the heat transfer coefficient of existing metal heat sinks is not very good. Therefore, heat sinks made of ceramic materials with better heat transfer characteristics appear on the market in order to achieve better heat dissipation effects.

Ceramic heat sink classification

There are aluminum oxide heat sink, aluminum nitride heat sink and silicon carbide heat sink.

There is the performance comparison between usual heatsink VS ceramic

Temperature of Heater itself (Without heat sink)	Temperature of heater with heat sinks
Temperature of Heater itself (Without heat sink)	Usual heatsink	Ceramic heatsink	Difference ΔＴ
150℃	90.3℃	86.7℃	3.6℃
180℃	119.1℃	110.8℃	8.3℃
250℃	175.4℃	164.3℃	11.1℃

Advantages of Ceramic Heat sink:

1. Do not store heat, and dissipates heat directly, which is fast and reduces the influence of the insulating layer on thermal efficiency;

2. The polycrystalline structure of the ceramic heat sink enhances heat dissipation. Year-on-year conditions, surpassing most thermal insulation materials on the market;

3. The multi-directional heat dissipation of the ceramic heat sink accelerates heat dissipation;

4. High thermal conductivity, high voltage resistance, high temperature resistance, wear resistance, high strength, oxidation resistance, acid and alkali resistance, long service life, and low thermal expansion coefficient, ensuring that it can be used in high and low temperature environments or other harsh environments.

5. Effective in anti-interference (EMI) and anti-static;

6. It is made of natural organic materials, which meets the requirements of environmental protection;

7. Small in size, light in weight, high in strength, saves space, saves materials, saves freight, and is more conducive to the rational layout of product design;

8. Withstand high current, high voltage, prevent leakage and breakdown, has no noise, and will not generate coupling parasitic capacitance with power tubes such as MOS, and thus simplifies the filtering process; the required creepage distance is higher than that of metal bodies The short requirement further saves board space, which is more conducive to the design of engineers and the passing of electrical certification.

Applications:

1. Ceramic heat sinks are mainly used in high-power equipment, IC MOS tubes, IGBT chip-type heat-conducting insulation, high-frequency power supplies, communications, mechanical equipment, high-current, high-voltage, high-temperature and other product components that require heat conduction and heat dissipation insulation.

2. LED lighting, high-frequency welding machine, power amplifier/audio, power transistor, power module, chip IC, inverter, network/broadband, UPS power supply, high-power equipment, etc.

Injection Molding of Aluminum Nitride Ceramics

Ceramic Injection Molding (CIM) is an emerging technology for manufacturing complex-shaped ceramic parts, and it has incomparable unique advantages in the preparation of complex small parts. With the continuous expansion of the industrialization scale of electronic ceramics worldwide in recent years, the attractive application prospect of CIM technology is worth looking forward to. The process mainly includes material preparation, injection molding, debinding, and sintering.

Injection Molding of Aluminum Nitride Ceramics

① Material preparation. The sinterable ceramic powder is mixed with a suitable organic carrier (binder) at a certain temperature to provide the fluidity and green strength necessary for ceramic injection molding; the mixture system of ceramic injection molding is a high-solid Viscous suspension (or melt) with phase volume fraction, the volume fraction of solid particles (ceramic powder) reaches 50-70%.

② Ceramic Injection molding. After kneading, the extruded and granulated mixed material is heated and softened at a certain temperature by an injection molding machine, and then injected into the mold at high speed under pressure, cooled, and re-solidified in the mold to obtain the desired shape of the injection molded blank. Mold shape, mold temperature, feeding temperature, injection pressure, holding time, cooling speed, etc. all have an impact on the quality of the billet.

③ Debinding. The organic binder for injection molding is about 25-50% (volume percentage). How to effectively remove such a large amount of organic matter without affecting the distribution of particles is a very difficult thing. Degreasing is a physical and chemical reaction process, and its process control is complex, which may easily cause defects such as cracking, deformation, and voids in the green body. Therefore, whether the degreasing can be successfully completed is very important for ensuring the quality of the green body, high product qualification rate, reducing energy consumption, and large-scale production.

④ Sintering. After degreasing, ceramic injection molded products will have many pores inside and low density, so high-temperature sintering is required to obtain high-performance dense products. The sintering speed is related to viscous flow, condensation, volume diffusion, surface diffusion, etc. For non-oxides, nitrogen or other gases are generally used instead of air, and the sintering of oxide ceramics is generally carried out under air. Sintering is generally carried out at normal pressure, but for some ceramics that are easy to evaporate at high temperatures, it must be carried out under pressure.

Advantages: high density, uniform density distribution, can be used for complex shape green body molding, and high molding precision, no need for post-processing.

Disadvantages: Defects such as underfill, flash, weld marks, and air pockets are prone to affect the sintering of AlN ceramics.

Why Consider Ceramic Feedthroughs

Ceramic feedthroughs are ceramic-to-metal fabrications that are utilized to transmit electrical signals, high currents/gases/fluids, or high voltages from between external sources to a hermetically-sealed chamber.

Why Consider Ceramic Feedthroughs

Electrical connectors and feedthroughs require well-engineered materials. In its simplest form, epoxy or glue can be used to seal a joint, but a more robust solution might use an elastomer Oo-ring as a mechanical seal. But in the most demanding applications and to prevent leakage over, fluctuating changes of temperature, humidity, and pressure, a ceramic seal can be most effective.

These assemblies are made to provide high mechanical strength and electrical insulation. They are hermetically sealed and maintain very high levels of vacuum. Joint integrity is maintained even at extreme temperatures and in harsh environments.

Feedthrough Applications

Typical uses of ceramic feedthroughs:

Mass spectrometry

Gas detection

High-vacuum connectors

Transmission and scanning electron microscopes

Particle accelerators

Nuclear detectors

Medical industry applications

X-ray equipment

Scanners

Imaging equipment

Aerospace industry application

Satellite propulsions

Sensors

Engines

Power tubes

Optoelectronics

Gas lasers

Rechargeable batteries

Deep sea penetrators and repeater

INNOVACERA supplies the most commonly used ceramic-to-metal bonded feedthroughs, which are utilized in many different applications with proven reliability.

If you have any inquiries, pls feel free to send them to us.

Pyrolytic Boron Nitride/PBN Ceramic MBE Crucible for Microelectronics Industrial

The molecular beam epitaxy ( MBE Crucible ) method is one of the methods to produce gallium arsenide epitaxy wafers. This method can be used to produce multiple, multilayer, homogenous, heterogenous, superlattice, and quantum well epitaxy materials. High crystal purity and good chemical stability. MBE Crucible is mainly used to synthesize semiconductor single crystal and ⅲ-ⅴ group compounds by MBE method.

Pyrolytic Boron NitridePBN Ceramic MBE Crucible for Microelectronics Industrial

MBE Crucible Main Features
1. Can make large crucible (maximum diameter 12inch, maximum height 17inch);
2. High density (up to 2.2g/cm3);
3. High purity (>99.99%);
4. Not easy to crack (high interlayer strength).

PBN Properties

Technical Parameter			BN	PBN
Mechanical	Density	g/cm3	2.2~2.3	2.1-2.19
	Color	—	White	White
	Water Absorption	%	0	0
	Vickers Hardness	Gpa	(Moh’s=2)	(Knoop=691)
	Flexural Strength (20°C)	Mpa	100	243.63
	Compressive Strength (20°C)	Mpa	287	—
Thermal	Thermal Conductivity (20°C)	W/m.K	35	43-60
	Thermal Shock Resistance (20°C)	Δ T(C)	—	—
	Maximum Use Temperature	°C	2400	2200
Electrical	Volume Resistivity (25°C)	Ω.cm	10 ^ 8~10 ^ 13	3.11×10 ^ 11

Pyrolytic Boron NitridePBN Ceramic MBE Crucible for Microelectronics Industrial (2)

Vacuum Interrupter Ceramic Tube

Ceramic Insulator Tubes are used in vacuum interrupters for medium voltage switch gears (approx. 6kV to 80kV). It is a specialized Alumina material with high insulation resistance, good mechanical strength, and so on.

The Mo-Mn metallization with nickel plating allows customers to assemble hermetically sealed products and In-house electrode brazing capability.

Our factory has dedicated production lines, capable of high quality and mass production.

Any specific requirements, pls feel free to contact us.

Vacuum Interrupter Ceramic Tube

Material Properties:

PROPERTY	UNITS	95%Al2O3	99%Al2O3
Dielectric Strength	kv/mm	18	20
Dielectric Loss	25°C @ 1MHz	0.0004	0.0002
Volume Resistivity	25°C ohm-cm	>10¹⁴	>10¹⁴
Bulk Density	G/cm3	3.8	3.9
Thermal Conductivity	W/mk	24	28

Applications:

Vacuum interrupters of switchgear, medium voltage range (approx. 6KV to 80KV)
Vacuum switch
Vacuum relay

Aluminum Nitride Materials Used As Heat Resistant Material

Aluminum nitride materials can be used as high-temperature insulating parts because of their excellent insulating properties and thermal stability.

In addition, aluminum nitride and metals such as aluminum, copper, silver, and platinum and semiconductor materials such as gallium arsenide are difficult to infiltrate. It is suitable for crucibles, thermocouple protection tubes, and sintering utensils, and can also be used as containers and treatment of corrosive substances. device.

In addition, aluminum nitride is very stable to molten salt, and it is expected to be used as a high-temperature gas turbine for corrosion-resistant parts such as magnetic fluid power generation (MHD). Since aluminum nitride has a low vapor pressure in a vacuum and is not easy to volatilize at high temperatures, it can be used as an evaporator such as gold.

Aluminum nitride is very stable up to 2000°C in a non-oxidizing atmosphere, so it can be used as an aggregate of refractory materials used in a non-oxidizing atmosphere.

Below is the properties of Aluminum Nitride materials:

Chemical formula	AlN
Color	Gray
Density	3.3 g/cm 3
Thermal conductivity	160 ~ 190 W/m. K
Thermal Expansion ( x10 -6 / ℃ )	2-3.5
Dielectric strength	≥17KV/MM
Dielectric Constant (at 1MHZ)	8-10
Loss Tangent (x10 -4 @1MHZ)	2.0
Volume Resistivity	≥10^14 ohm-cm

Below is the aluminum nitride crucible we make, any other customized shape could be made. For more information, pls consult with us.

Aluminum Nitride Materials Used As Heat Resistant Material

POROUS CERAMIC VACUUM CHUCK

Characteristics of porous ceramic vacuum chuck

1). Ceramic Material: SiC, Al2O3; Base material: stainless steel/aluminum alloy, ceramic, marble

2). Porous Ceramic Porosity: 40%

3). Porous Ceramic Pore Size: 1-100μm

4). Size customization; flatness≤3μm;

5) The unique air circuit design and packaging process of aviation aluminum alloy base can realize selective vacuum area adsorption.

Application field of porous ceramic vacuum chuck

1). It can absorb OLED, LCD, wafers, and other smooth and flat objects.

Please note: the contact area between the adsorbed substance and the ceramic should not be less than 10*10mm (the larger the adsorption area, the stronger the adsorption force).

When absorbing objects, it is not necessary to cover the unused area.

2). It can be used in both directions. Adsorption by vacuum and suspension of objects by positive pressure

Porous Ceramic Steel Disc

How to use the porous ceramic vacuum chuck

As shown in the figure, the internal structure of the vacuum chuck is divided into three areas: A, B, and C. When each area is vacuumed separately, the area covered by the ceramic can form a strong negative pressure.

Connect the three area air pipes in parallel to a vacuum generator, and install a solenoid valve as required.

Connect the air source (above 0.6Mpa), and open the air circuit in the corresponding area according to the size of the object.

POROUS CERAMIC VACUUM CHUCK Equipment

Precautions in the use of porous ceramic vacuum chuck

1). Do not blow air under positive pressure. (If there is a need for air suspension, it can be customized)

2). Handle with care, do not scratch or hit the ceramic surface with hard objects, to prevent deformation from affecting accuracy and ceramic cracking.

3). Do not heat, the thermal shrinkage of the aluminum alloy /stainless steel base may cause the ceramic extrusion to crack.

4). It should not be contaminated with oil, glue, paint, and other pollutants, and should be used in a dust-free and oil-free environment as much as possible to prevent micropore blockage.

5). If there is dust and dirt on the surface, it can be pasted and removed with non-residual adhesive tape multiple times, or washed with a high-pressure water gun.