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What Are The Types Of CO2 Laser Tubes

The laser tubes usually used in CO2 laser machines are categorized into DC glass、RF metal tubes and ceramic tubes. Let’s delve deeper into some key aspects of these three common core types so you can choose the best one for your machines.

1. Glass Laser Tubes

Glass laser tubes are cylindrical tubes made of glass that are used as a medium for generating laser beams. It can come in various sizes and shapes, depending on the specific application and power requirements. Glass is a poor thermal conductor, which means circulating water is needed to assist in the removal of heat. So nearly all glass tubes need to be water-cooled, without a water-cooling system, a glass laser tube would overheat and become inoperable.
Glass CO2 laser tubes rely on direct current, DC, to excite the carbon dioxide gas. Machines with DC tubes are mostly used for nonmetal materials, such as acrylic, wood, leather, plastic, paper, or bamboo.

2. Metal Laser Tubes

Metal laser tubes are sealed metal chambers made of metal and ceramic, which contain the laser gas mixture. They are air-cooled and their gas is excited by radio frequency alternating current (RF). Properly regulating temperature only requires fans, which are built directly into laser machines.
Metal is typically stainless steel or other durable alloys and ceramics is usually alumina, they are brazed to form a feedthrough of up to 1.0 x 10 -10 atm-cc/sec. In conclusion, metal laser tubes are crucial components of industrial laser cutting systems. They provide the power and control required to generate laser beams for metal cutting, marking, and welding applications. Whether using CO2 or fiber laser technology, these tubes allow for precise and efficient processing of various metal materials.

3. Ceramic Core Tubes

Ceramic core is manufactured by fusing two halves of the ceramic core together at 800°C. CO2 lasers have evolved from glass-tube, high-voltage designs to metal-tube RF electrode technology. But recently it’s common for CO2 Laser manufacturers to use pure ceramic core inside their laser tubes.

Advantages and Disadvantages of Different Laser Tubes:

	Glass Laser Tubes	Metal Laser Tubes	Ceramic core tubes
Advantage	lower cost	1. Engraving quality and speed higher. 2. Maintenance cost lower. 3. Longevity and it is 4-5 times longer than glass tubes.	The gas will not pollute and leak.
Disdvantage	Tubes require frequent replacement and have a short longevity.	Higher cost	1.Higher cost 2.Difficult maintenance 3. In comparison with a metal-sealed laser, another disadvantage of ceramic core lasers is their lower relative heat conductivity.

Aluminum Nitride Ceramic Part Typical Applications

Compared with other ceramic materials, AlN has a thermal expansion coefficient that matches silicon and excellent thermal conductivity, which makes it more suitable for use in the electronics industry. Aluminium Nitride Ceramic Material Properties is as bleolw.

Properties	Unit	Value
Color	–	Dark Gray
Main Content	%	96% ALN
Bulk Density	g/cm3	3.335
Water Absorption	%	0
Flexural Strength	MPa	382.7
Dielectric Constant	MHz	8.56
Coefficient Linear Thermal Expansion	/℃，5℃/min, 20~300℃	2.805×10-6
Thermal Conductivity	30 Degree Celsius	≥170
Chemical Durability	mg/cm2	0.97
Thermal Shocking Resistance	–	No cracks
Volume Resistivity	20 Degree Celsius (Ω·cm)	1.4×1014
Dielectric Strength	KV/mm	18.45
Surface Roughness Ra	μm	0.3-0.5
Camber	Length ‰	≤2

Aluminum nitride can also be used in heat exchangers, crucibles, protective tubes, casting molds, piezoelectric ceramics and films, thermally conductive fillers, etc. Below is some application of Aluminum nitride ceramic components.

1. Heat dissipation substrate and electronic device packaging

Heat dissipation substrates and electronic device packaging are the main applications of AlN ceramics. Aluminum nitride ceramics have excellent thermal conductivity, thermal expansion coefficient close to silicon, high mechanical strength, good chemical stability, and are environmentally friendly and non-toxic. It is considered an ideal material for a new generation of heat dissipation substrates and electronic device packaging, and is very suitable for hybrid power switches. It is a material for packaging and microwave vacuum tube packaging shells, and is also an ideal material for large-scale integrated circuit substrates.

2. Structural ceramics

Electrostatic chucks for wafer processing are a common structural ceramic application. Aluminum nitride structural ceramics have good mechanical properties, high hardness, better toughness than Al2O3 ceramics, and are resistant to high temperatures and corrosion. Taking advantage of the heat resistance and corrosion resistance of AIN ceramics, it can be used to make high-temperature corrosion-resistant parts such as crucibles, Al evaporation dishes, and semiconductor electrostatic chucks.

3. Functional materials

Aluminum nitride can be used to manufacture high-frequency and high-power devices that can be used at high temperatures or in scenarios where certain radiation exists, such as high-power electronic devices, high-density solid-state memories, etc. As one of the third-generation semiconductor materials, aluminum nitride has excellent properties such as wide bandgap, high thermal conductivity, high resistivity, good ultraviolet transmittance, and high breakdown field strength. AlN has a bandgap width of 6.2 eV and strong polarization. It is used in machinery, microelectronics, optics, surface acoustic wave device (SAW) manufacturing, high-frequency broadband communications and other fields, such as aluminum nitride piezoelectric ceramics and Film, etc. In addition, high-purity AlN ceramics are transparent and have excellent optical properties. Combined with their electrical properties, they can be used to make functional devices such as infrared deflectors and sensors.

4. Inert heat-resistant materials

As a heat-resistant material, AlN can be used as crucibles, protective tubes, pouring molds, etc. Aluminum nitride can still have stable performance in a non-oxidizing atmosphere at 2000°C. It is an excellent high-temperature refractory material and has strong resistance to molten metal erosion.

5. Heat exchange components

Aluminum nitride ceramics have high thermal conductivity, low thermal expansion coefficient, excellent thermal conductivity efficiency and thermal shock resistance. They can be used as ideal heat shock resistance and heat exchange materials. For example, aluminum nitride ceramics can be used as heat exchanger materials for marine gas turbines and Heat-resistant components of internal combustion engines. Due to the excellent thermal conductivity of aluminum nitride material, the heat transfer capacity of the heat exchanger is effectively improved..

Exploring the Thermal Management Capabilities of Ceramic Circuit Substrates

With the continuous development and advancement of electronic devices, high power density and high temperature have become one of the important challenges faced by modern electronic systems. Thermal management is a key factor in maintaining the reliability and performance stability of electronic devices. In this regard, this article will explore the thermal management capabilities of ceramic circuit substrates, introduce their applications in high-temperature environments, and discuss related technological advances and solutions.

Thermal conductivity of ceramic circuit substrates:

Ceramic materials have good thermal conductivity. In comparison, traditional organic substrate materials have low thermal conductivity. Common ceramic circuit substrate materials, such as aluminum nitride (AlN) and silicon nitride (Si3N4), have high thermal conductivity, respectively 170-200 W/(m·K) and 80-140 W/(m·K ). This allows the ceramic circuit board to dissipate heat more effectively, improving thermal management capabilities. (INNOVACERA provides a variety of high-quality ceramic substrate materials).

Thermal transfer and thermal design:

In high power density applications, thermal transfer and thermal design are critical. The thermal conductivity properties of ceramic circuit substrates provide designers with greater flexibility and possibilities. Through reasonable heat dissipation design, such as adding heat sinks or thermal vias, the thermal management capabilities of ceramic circuit substrates can be effectively improved, heat can be quickly transferred to the surrounding environment, and the temperature of electronic components can be reduced.

Application in high-temperature environments:

Ceramic circuit substrates have excellent performance in high-temperature environments. Its high melting point and excellent thermal stability enable it to withstand high-temperature operations and maintain a low coefficient of thermal expansion. This makes ceramic circuit substrates ideal for many applications in high temperature environments, such as aerospace, energy, automotive electronics and power electronics. In these applications, ceramic circuit boards provide stable operation and provide excellent thermal management capabilities to ensure system reliability and performance.

Technology progress and solutions:

In order to further improve the thermal management capabilities of ceramic circuit substrates, researchers continue to explore new technologies and solutions. Here are some common technology advances:
A. Heat transfer enhancement materials: By adding heat transfer enhancement materials, such as metal probes or nanopins, the thermal conductivity of the ceramic circuit substrate can be improved, thereby enhancing its thermal management capabilities.
B. Thermal interface materials: The selection and application of thermal interface materials is very important for optimizing thermal management. High thermal conductivity thermal interface materials can improve heat transfer efficiency, reduce thermal resistance, and enhance thermal management capabilities.
C. Simulation and simulation tools: The use of thermal simulation and simulation tools, such as finite element analysis (FEA) and computational fluid dynamics (CFD), can help designers evaluate and optimize the thermal management performance of ceramic circuit substrates and provide accurate thermal design solution.
Conclusion: Ceramic circuit substrates show great potential in thermal management due to their excellent thermal conductivity and thermal stability. Through reasonable heat dissipation design and the application of thermal conductivity enhancement materials, the effective heat dissipation and heat dissipation capacity of ceramic circuit substrates can maintain the reliability and performance stability of electronic equipment. In high-temperature environments, the excellent performance of ceramic circuit substrates has become an ideal choice for many application fields. With the continuous advancement of technology and in-depth research, the thermal management capabilities of ceramic circuit substrates will be further improved, providing more reliable solutions for future high-performance density electronic systems. If you need ceramic substrates, ceramic heat sinks, etc. please feel free to contact us. INNOVACERA not only have a variety of ceramic materials, but also are good at various processing techniques, such as DBC, DPC, AMB.

Ceramic Substrates For Power Modules

Ceramic substrates are materials with unique thermal, mechanical, and electrical properties that make them ideal for demanding power electronics applications, typically used in Power Modules.
The most recent applications of power modules are for electric vehicles (EVs) and hybrid electric vehicles (HEVs), call for higher voltage and power from smaller circuits, requiring circuit materials capable of providing high voltage isolation with the efficient dissipation of heat from densely packed semiconductor devices such as IGBTs and MOSFETs. DBC and AMB Ceramic Substrates for Power Modules are connection components in which copper plates are bonded to each surfaces of a ceramic plate. These ceramic substrates are with a high thermal conductivity and a excellent electric conductivity of copper and a high insulation property. The high electrical conductivity of copper supports high current; the excellent dielectric properties of the ceramic substrates enable the high isolation needed for densely packed circuits in power modules. The CTE of ceramic substrates aligns more closely with that of the metal traces on the substrate and the components soldered to the substrate. That helps minimize stresses that can lead to component and solder joint fractures.
Ceramic substrates are implying copper layers on the ceramic plates, then etching with circuit pattern. The ceramic materials include Alumina, Aluminum Nitride, and Silicon Nitride. Copper is bonded to ceramic with different methods, including direct bond copper (DBC), direct plating copper (DPC) or active metal brazing (AMB) processes.

Materials comparison:

1. Aluminum Oxide Substrates
The most cost-effective material and good performance
Lower thermal conductivity

2. Aluminum Nitride Substrates
High thermal conductivity 170W/mK
CTE (Coefficient for Thermal Expansion) very close to silicon
High flexural strength

3. Silicon Nitride Substrates
Good flexural strength
Excellent fracture toughness
Good thermal conductivity

Hot-pressed Aluminum Nitride Cover Plate Heater

Glad to share with you our new arrival products-Hot-pressed Aluminum Nitride Cover Plate Heater with thinnest thickness 0.75mm. It can be said that it is the first time in China that a highly difficult hot-pressed aluminum nitride disc has been produced. It is difficult to make due to below reasons:

1.The material is very difficult to machine due to the high hardness and brittle, so it is very easily to have chips or scratches when handling or machining which lead to very high rejection rate. Anyway it’s a successful start, and we believe we could make better and better.

2.Hot pressed aluminum nitride ceramics are sintered by vacuum hot pressing, the sintering process is more difficult than pressureless sintering. The aluminum nitride purity is up to 99.5%(without any sintering additives), and density after hot pressing reaches 3.3g/cm3, it also has excellent thermal conductivity and high electrical insulation. The thermal conductivity can be from 90 W/(m·k) to 210 W/(m·k).

3.The thinnest thickness is about 0.75mm which also make it more difficult to machine.

The application of the hot pressed aluminum nitride cover plate heater：
Cover plate heater for semiconductor

Other Application:
– Cover plates and MRI equipment(Magnetic Resonance Imaging)
– High-power detectors, plasma generators, military radios
– Electrostatic chucks and heating plates for semiconductors and integrated circuits
– Infrared and microwave window material

Features:

High thermal conductivity
Expansion coefficient can match with semiconductor silicon chips
High insulation resistance and voltage withstand strength
Low dielectric constant and low dielectric loss
High mechanical strength

Typical Specification:

Purity:	>99%
Density:	>3.3 g/cm3
Compress Strength:	>3,350MPa
Bending Strength:	380MPa
Thermal Conductivity:	>90W/(m·K)
Coefficient of Thermal Expansion:	5.0 x 10-6/K
Max. Temp:	1,800°C
Volume Resistivity:	7×1012 Ω·cm
Dielectric Strength:	15 kV/mm

Porous Ceramic Application: Vacuum Chuck

Introduction: Porous ceramics are ceramic materials with fine pore structure. They are widely used in various fields due to their high porosity, high air permeability, high thermal stability and high mechanical strength. Among them, vacuum suction cups are an important application direction of porous ceramics. This article will introduce in detail the application of hole-like ceramics in vacuum suction cups, including materials, manufacturing processes, application fields, and development trends.

Porous ceramic materials include alumina and silicon carbide, which have excellent physical and chemical properties and can maintain stable performance in harsh environments such as high temperature, high pressure, and corrosion.

Porous ceramic materials have the following performance characteristics:

1. High specific surface area: porous ceramic materials have a high specific surface area, which is beneficial to adsorbing gas molecules and improving the adsorption performance of the vacuum suction cup.
2. High temperature resistance: porous ceramic materials have a high melting point and can maintain stable performance in high temperature environments.
3. Corrosion resistance: porous ceramic materials have good chemical stability and can resist erosion by various corrosive media.
4. Wear resistance: porous ceramic materials have higher hardness and better wear resistance.

Manufacturing process:

The manufacturing process of porous ceramics mainly includes the steps of mixing, shaping, drying, sintering and processing.
Molding and sintering are key steps in manufacturing porous ceramics. During the molding process, ceramic powder needs to be made into green embryos with regular shapes and sizes. During the sintering process, the blank is sintered at high temperature to form a ceramic product with a porous structure.

Application areas of porous ceramic vacuum chucks

Porous ceramic vacuum chuck are widely used in many fields due to their excellent performance, including:
1. Industrial automation: porous ceramic vacuum suction cups can replace traditional mechanical clamps in automated production lines to achieve fast and accurate material handling, such as automobile manufacturing, food processing, electronic manufacturing, etc.
2. Medical equipment: porous ceramic vacuum suction cups can be used to grab and fix surgical instruments to improve the accuracy and safety of surgical operations. and hemodialysis, etc.
3. Aerospace: porous ceramic vacuum suction cups can be used for surface cleaning and maintenance of spacecrafts, sample grabbing in space experiments, and logistics transmission of space stations, etc.

Future development of porous ceramic vacuum chucks

As the application of porous ceramic vacuum suction cups continues to expand in various fields, the future development prospects are very broad.
Regarding the future development of porous ceramic vacuum suction cups, we can discuss it from the following aspects:
1. Material optimization: further study the preparation method of new porous ceramic materials and improve the performance of the materials to meet the application needs in different fields.
2. Application expansion: Explore the application of porous ceramic vacuum suction cups in more fields, such as robotics, marine engineering, etc.
3. Intelligentization: Combined with artificial intelligence technology, it realizes intelligent control and optimization of porous ceramic vacuum suction cups and improves its work efficiency.

Categories of vacuum Chuck:

1. Thinning Chucks
2. dicing suction Chucks
3. cleaning suction Chucks
4. printing suction Chucks
5. carrying suction cups/Transportation chuck

Application machine model of vacuum chuck

1. DFG8540
2. 7AF-II
3. DAS321/DAD341
4. DAD3350
5. ADT7100
6. A-WD-100A

Structure of vacuum suction chucks

Porous Ceramics Applications: Atomizer Cartridges, Atomizing Core, Atomizer Core

Preface: atomization, the process of turning liquid into small droplets.
Nebulization products: humidifier, facial steamer, fog machine, medical nebulizer and so on.
With the development of science and technology, the atomization method is also diversified: high-pressure gas atomization, ultrasonic atomization, microwave heating atomization, resistance heating atomization.
As the Key of the atomization technology, the atomization core determines the atomization effect and experience.
Nowadays, ceramics in the field of fogging technology burst of vitality, become the standard of high-quality fog core.

1. Why use ceramic as material and what is the principle of atomization?

Ceramic is not the only material applied to the atomizing core in electronic atomizers.
Fiber rope, organic cotton, non-woven fabric and other materials have been applied to make atomizing core.
The ceramic applied in the atomizer core is not the same as the ceramic we commonly see on the dining table, it is a special kind of “porous ceramic“.

This is a photo of the ceramic after magnifying it tens of thousands of times. In a ceramic core, there are about hundreds of millions of micro and nano pores like this one.

The main components of ceramic atomizer core are originated from nature, after high temperature sintering, a lot of tiny micro-pores are formed inside, and its average pore size is equivalent to one-fifth of a hair strand.
These tiny microporous holes are the key to the ceramic atomizer core’s ability to achieve stable liquid conduction and liquid locking functions. Due to surface tension and capillary effect, the liquid can penetrate into the atomizer core evenly and adsorb on the surface of the atomizer core.

2. What are the advantages of ceramic atomizer core?

Compared with the atomizing core composed of other materials, such as heating wire and fiber rope, heating wire and organic cotton, the Ceramic atomizing core is characterized by a faster rise in temperature during the heating process, better temperature uniformity and more precise control of the temperature range.
This can reduce the production of aldehydes and ketones in the process of use to a greater extent, thus ensuring the safety of the use process.

What are the applications of ceramic heat sinks for thermal management?

Highly thermally conductive ceramic heat sinks made of aluminum oxide and aluminum nitride offer many possibilities in thermal management of high-performance electronics, photovoltaics, LEDs and other applications. These products offer high electrical insulation, chemical resistance, corrosion resistance and numerous benefitsapplication.

Cooling in Automotive Engineering

Hybrid and electric vehicles (HEV hybrid vehicles, BEV pure electric vehicles) especially require drive motors with the highest possible power output, long service life and extremely high reliability in the smallest space.
This is where efficient liquid coolers offer decisive advantages: due to their very low thermal resistance, both thermally and electrically, since the ceramic heat sink itself is already an excellent insulator.
1. Thermal management of inverters and converters for hybrid and electric vehicles
2. Insulating ceramics for high-voltage PTC heating modules in hybrid and electric vehicles
3. Electrical insulation and cooling for lighting applications (laser lamps, LEDs)
4. Cooling of start-stop system
5. Battery Thermal Management: Uses the same ceramic components for heating during startup and cooling during operation
6. Cooling solutions for electric vehicles

Cooling of power electronic equipment

In the field of power electronics, heat sink chip technology can reduce the thermal resistance between the heat source (chip) and the heat sink by half compared to traditional cooling system structures, depending on the structure.
1. Electronic power modules with extremely high packaging density
2. Frequency converters in wind turbines

Cooling in energy production

High concentration photovoltaics (CPV/HCPV) is a futuristic technology that harvests energy from light: sunlight beams are tightly bundled together and concentrated on a small surface using high-power solar cells. If not cooled effectively, they will be destroyed in a short time.
In order to operate a CPV system at maximum efficiency, effective cooling is required, even during operation.

Cooling in LED lighting technology

LEDs have many advantages over traditional light bulbs. A key benefit is significantly longer lifespan. However, this depends heavily on the temperature the LED chip reaches during operation. A general rule of thumb is: if the operating temperature is reduced by 10°C, the life of the product will be doubled. This is why cooling LED chips is so important.
In addition, circular heat sinks with direct metallized circuits on ceramics can be used in LED technology, such as for shop and store lighting, to achieve the brightest lighting with the lowest power consumption.
1. Store and shop lighting
2. UV hardening
3. Parking and street lighting
4. Facade lighting
5. Navigation lighting
6. Stadium spotlight
7. Industrial lighting
8. High-speed camera lighting
9. Car headlights

A Brief History Of Oxygen Sensors

Function

The oxygen or lambda sensor in a properly functioning exhaust system monitors the A/F ratio, as often as one hundred times per second, and reports this information to the vehicle’s ECU or engine control unit (also referred to as the PCM or ECM). The proper adjustments are then made to ensure that this ratio is ideal or stoichiometric, helping the automobile burn fuel more efficiently. Most oxygen sensors use the core material of zirconia, which produces voltage in relation to the amount of oxygen in the exhaust.

Evolution

Oxygen sensors were developed by the Robert Bosch Company and first used on Volvo applications in the late 1970’s. Originally, automotive oxygen sensors had only one or two wires and were made from zirconia in a thimble shape. They relied upon the heat in the exhaust system to warm them to their required operating temperature. The problem associated with this concept was that it took a very long time for the sensors to go from nonoperational (thus leaving the ECU in open loop mode) to operational (which is necessary for closed loop mode), typically over a minute. Some automobile manufacturers purposely retarded ignition timing to heat the exhaust to afford faster oxygen sensor and catalyst warm up. When located close to the engine (a requirement to warm the sensors to the adequate operating temperature) it was not possible to monitor the exhaust gases from both engine banks – another downfall of early sensor designs.
In the early 1980’s, oxygen sensor manufacturers added a small rod type heater in the center of the thimble that warmed the ceramic thimble to its operating temperature much faster. The heated sensors could be mounted downstream next to the catalytic converter – a more desirable location because the exhaust gases were in a more homogenous state and the potential for sensor overheating was reduced dramatically. The first versions were three wire sensors that employed a case ground for the sensor signal. Later applications employed four wire versions with an isolated ground.
Starting in the early 1990’s for California vehicles & 1996 for the other 49 states, OBDII controls were implemented. The requirements of the oxygen sensor increased dramatically. New technologies were developed and sensors were placed in more locations, thus increasing their feedback to the ECU. The current narrow band sensors, which only allowed for readings of “rich” or “lean,” were replaced. The new generation of four and five wire wide band sensors are now being employed on many vehicle applications. These sensors allow for exact measurements of A/F ratio, allowing for true emission control.
While the first sensor equipped vehicles had a single sensor, today’s vehicles can have up to eight. The original one wire thimble sensor has been joined by heated, planar, titania, FLO (fast light off), UFLO (ultra-fast light off), wideband and A/F ratio sensors. The modern oxygen sensor, due to its sophistication and placement, is what allows for the fuel injected and low emission engines of the modern vehicle.

Typical Sensor Components

Thimble type

Planar type

Innovacera offer both thimble and planar type of oxygen sensor heaters, if you have more interesting, pls contact with us.

What kind of heating element can have a built-in K-type thermocouple?

INNOVACERA recently launched a small aluminum nitride ceramic heating element. Made of aluminum nitride ceramic with high thermal conductivity. Has excellent heat dissipation and electrical insulation properties.
With its properties of electrical insulation and excellent thermal conductivity, Aluminum Nitride Ceramics is ideal for applications where heat dissipation is required. In addition, since it offers a coefficient of thermal expansion (CTE) near that of silicon, and excellent plasma resistance, it is used for semiconductor processing equipment components.

Small Aluminum Nitride Ceramic Heating Element Characteristics

The heater can have a built-in K-type thermocouple, so it has good temperature sensing characteristics, improves its responsiveness to rapid heating and cooling, and can be used safely.
Fast heating and cooling
The aluminum nitride substrate with high thermal conductivity can be used to achieve rapid heating and cooling, and the thermal expansion rate can be used according to the material properties to design under high power density, so it can also be used for rapid heating and cooling (both 150℃/ sec) temperature cycle.
Excellent electrical performance
Excellent insulation and voltage resistance at high temperatures

Small Aluminum Nitride Ceramic Heating Element Features

Thermal properties		Physical properties		Electrical characteristics
Thermal conductivity	150(W/mK)	Density	3.2(g/cm3)	Voltage	12V~240V
Thermal expansion coefficient	4.5 (ppm/℃）	Hardness	1050 (Hv@500g)	Leakage	＜1mA
—	—	Flexure strength	＞250 （Mpa)	Capacitivity	8.9
—	—	—	—	Insulation voltage	15KV/mm

Small Aluminum Nitride Ceramic Heating Element Application

Automotive Components
Glow Plug
Igniter for Cabin Heater
Heater for Oxygen Sensor
Kerosene and Gas Appliances
Igniter
Heater for Vaporizer
Industrial Heater Applications
Heater for Soldering Iron
Heater for Hair Iron
Bonding Heater
Seal Heater
Water-Heating Applications
Heater for Toilet Water
Bath Water Heater
Steam Boiler Heater
Liquid Heater for Small Appliances

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