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High Temperature Magnesia Stabilized Zirconia

INNOVACERA presented new material High temperature Magnesia Zirconia which is also called Magnesium Stabilized Zirconia Ceramic. It is a great refractory and insulating material due to high oxygen ion conductivity, high strength and toughness, and good themal shock resistance. it has a clean melt at temperatures above 1900’C and above and is specially manufactured for melting superalloys and precious metals. its superior thermal shock resistance to temperatures reaching up to 2200℃.

The Magnesia Stabilized Zirconia is with porosity 1-18%, so it’s different from normal MgO-ZrO2. This material is often used as sizing nozzles in continuous casting,ladle slide plate, setter plate in metal powder industry, gas atomizing nozzle.

Sizing nozzle for molten steel
The sizing nozzle made of Magnesia Zirconia is with very high properties including high mechanical strength, very good thermal shock resistance, good corrosion resistance, erosion resistance and low thermal expansion.

The sizing nozzles are installed at the bottom of the continous casting tundish. The molten steel will flow into a mold through the sizing nozzles. The diameter of the nozzle can be changed by customers’ requirement.

MSZ plate for Ladle Skateboard
The Magnesia Zirconia plate is often used to inlaid with ladle slide which is also working in continuous casting of high oxygen steel, high calcium steel, high manganese steel and other steels. The Zirconia (ZrO2) plate is with high corrosion resistancce and low expansion. Then it will increase the woking life of the stateboard, reduce the cost. The dimension can also be customized.

Magnesia Stabilized Zirconia Setter Plate
Due to MSZ with good chemical resistance , high temperature resistance and no chemical reaction with fired ceramic parts, it’s widely work as setter plate ceramic capacitors, sensitive parts, magnetic materials and other electronic components.
Max working Temperature: 2600℃
Working Environment: Atmospheric Environment, Vacuum, Atmospheric Reduction

Gas Atomizing Nozzle for Metal Powder Industry
MSZ nozzle is an ideal choice for almost all common metal and alloy powders. The working temperature is 2200℃ max in air, vacuum or gas protection environment.

Introduction of Mass Spectrometer Filament

INNOVACERA is glad to offer new standard filament assemblies, a critical component in mass spectrometry applications for the analytical and medical industries.

Principle of mass spectrometer filament

Mass spectrometer filament is also called ion source filament or cathode filament. It is mainly made of high melting point metals such as tungsten (W) alloy or molybdenum alloy. Its function is similar to that of ordinary filaments. It mainly produces electron emission under high pressure and excites gaseous molecules into ions, thereby generating the charge-to-mass ratio signal required for mass spectrometry.

These filament supports are manufactured using 96% alumina, selected for its good electrical insulation and high temperature stability. Customers can choose between two and four-pin options, with the pins brazed into the alumina insulator ready for filament welding. Our brazing process makes the filament considerably more resistant to higher temperatures, around 700°C compared with standard adhesives, which can only typically withstand up to 350°C.

The function of the mass spectrometer filament

In a mass spectrometer, the mass spectrometer filament is the main part of the ion source. Its role is to excite gaseous molecules into ions, and then screen and measure the charge-to-mass ratio. It is one of the core components of the mass spectrometer for mass spectrometry analysis.

The working principle of the mass spectrometer filament mainly involves the emission of electrons after being heated in a vacuum. These electrons are accelerated through the ionization chamber under the action of the electric field, and lose energy after colliding with gas molecules, which eventually leads to the ionization of gas molecules to form positive ions. This process is the basis of the work of the ion source in mass spectrometry analysis.

Type of Electron beam emitter

TungstenFilament
LaB6 cathode
TFE(Thermal Field Emitter)
Code Cathode

Below is the detail properties.

Electron Source	Tungsten Filament	LaB6 Cathode	TFE	Cold Cathode
Luminance(A/cm²./sr)	-10⁵	-10⁶	-10⁸	-10⁹
Capacity range(eV)	1-3	1-2	0.6	0.3
working pressure(Pa)	＜10^-3	＜10^-5	＜10^-7	＜10^-8
Working temperature(K)	-2700	-1800	1700-1800	Room temp
Lifetime(time)	40-100	200-1000	＞5000	＞10000

Many years of manufacturing experience with ceramic-to-metal assemblies means we can work closely with customers to tailor designs to their requirements or produce constant runs of standard designs ensuring quick turnaround and delivery.

If you need customized filament, pls contact with us.

Hot-Pressed Aluminum Nitride Heater Cover Introduction

Hot-pressed aluminum nitride ceramics are sintered using vacuum hot pressing, a process more challenging than normal pressure sintering. The purity of aluminum nitride can reach 98.5% (without any sintering additives), and the density after hot pressing reaches 3.3 g/cm3. Additionally, it exhibits excellent thermal conductivity and high electrical insulation, ranging from 90 W/(m·K) to 210 W/(m·K).

The material is hard and brittle, making it difficult to process. Consequently, it is prone to nicks or scratches during handling or processing, leading to a high scrap rate.

The thinnest thickness is only 0.75 mm, and the processing difficulty is also relatively high.

Applications of hot-pressed aluminum nitride heater covers:

– Semiconductor Cover Heater

– Cover and MRI equipment (magnetic resonance imaging)

– High-power detectors – Plasma generators – Military radios

– Electrostatic chucks and heating plates are used for semiconductors and integrated circuits.

– Infrared and microwave window materials

Material Properties

1. Uniform microstructure

2. High thermal conductivity (70-180 W/(m·K)), customized through processing conditions and additives

3. High resistivity

4. Thermal expansion coefficient is close to that of silicon

5. Corrosion and erosion resistance

6. Excellent thermal shock resistance

7. The material exhibits chemical stability up to 980°C in H2 and CO2 atmospheres, and up to 1380°C in air (surface oxidation occurs at around 780°C; the surface layer protects the bulk material up to 1380°C).

Typical specifications:

Purity:	>98.5%
Density:	>3.3 g/cm3
Compressive strength:	>3,350MPa
Flexural strength:	380MPa
MGray and gray-black:	>90W/(m·K)
Coefficient of thermal expansion:	5.0 x 10-6/K
Max. temperature::	1,800°C
Volume resistivity:	7×1012Ω·A copper-oxygen eutectic form that successfully bonds with copper and oxides used as substrates
Dielectric strength:	15 kV/mm

Aluminum Nitride (AlN) is an excellent material when high thermal conductivity and electrical insulation properties are required, making it ideal for thermal management and electrical applications. Additionally, AlN is a common replacement for Beryllium Oxide (Be) in the semiconductor industry because it does not pose a health hazard when processed. The thermal expansion coefficient and electrical insulation properties of AlN closely match those of silicon wafer materials, making it a useful material for electronic applications where high temperatures and heat dissipation are often an issue.

AlN is one of the few materials that offer both electrical insulation and high thermal conductivity. This makes AlN very useful in high-power electronic applications as a heat sink and heat spreader.

What role does ceramics play in the semiconductor industry?

Semiconductor chips are ubiquitous in modern technology. They are essential in the evolution of various electronic devices and systems, including smartphones, smartwatches, computers, automobiles, big data, cloud computing, and the Internet of Things (IoT). Semiconductor equipment comprises thousands of components, whose performance, quality, and precision directly influence the reliability and stability of the equipment. Consequently, a significant amount of precision ceramic parts is required in semiconductor equipment.

Advantages of Precision Ceramics

Ceramics are utilized extensively due to their high hardness, high elastic modulus, high wear resistance, excellent insulation, good corrosion resistance, and low expansion. These properties make ceramics suitable for components in various semiconductor devices such as silicon wafer polishing machines, thermal processing equipment (epitaxy/oxidation/diffusion), lithography machines, deposition equipment, semiconductor etching equipment, and ion implantation machines. The main types of semiconductor ceramics include alumina, silicon nitride, aluminum nitride, boron nitride, and silicon carbide and so on. In semiconductor equipment, precision ceramics account for approximately 16% of the total value.

Applications of Ceramics in Semiconductor Equipment

Here is an overview of the different ceramic components used in various semiconductor processes:

1.Chemical Mechanical Planarization (CMP)
– Ceramic polishing tables
– Ceramic polishing plates
– Ceramic lapping plates
– End Effector
– O-ring ceramic sealing

2.Lithography machine
– Vacuum chuck
– Wafer chucks
– Ceramic worktables
– End Effector
– Ceramic working wheels
– Ceramic valves
– Ceramic filters

3.High-Temperature Processing (RTP/Epitaxy/Oxidation/Diffusion)
– Ceramic Insulators
– Ceramic substrates
– Wafer boats
– Furnace tubes
– Cantilever paddles

4.Deposition equipment
– O-ring ceramic sealing
– Ceramic valves
– Chamber covers
– Chamber liners
– Deposition rings
– Electrostatic chucks
– Ceramic Heating elements
– Electroplating insulators
– Vacuum break filters

5.Etching
– Domes
– Chambers
– Focus rings
– Ceramic Nozzles
– Electrostatic chucks
– End effector

6.Ion Implantation
– Ceramic Bearings
– Vacuum chuck
– Electrostatic chucks
– Ceramic Nozzles

Commitment to Quality and Innovation

Innovacera integrates advanced technologies and continuously pursues research and development. We approach each customer’s requirements with a scientific and rigorous attitude, striving for excellence to produce products that best meet our clients’ needs. We welcome detailed inquiries and look forward to providing more ceramic solutions and professional service for you!

Feel free to contact us with your specifications and requirements.

Ceramic Vacuum Brazing: Unlocking the Potential of Ceramic to Metal Bonds in High-Tech Applications

Ceramic materials, with their high melting points and excellent insulating properties, present significant challenges when it comes to joining them with metals. Traditional welding methods often struggle to create strong and reliable bonds. However, advancements in joining technologies have introduced Vacuum Brazing as a highly effective solution. This process not only overcomes the limitations of ceramics but also leverages the benefits of both materials to create composite components.

Vacuum brazing is particularly advantageous due to its ability to join ceramics and metals at high temperatures in a vacuum environment, which minimizes oxidation and other unwanted reactions. Ceramic-to-metal sealing process often involves the use of a brazing filler metal, which can be tailored to the specific materials being joined. One such technique is Active Metal Brazing, where a reactive element in the filler metal, such as titanium in Ag-Cu-Ti, activates the ceramic surface, facilitating a strong bond.

When considering the joining of ceramics to metals, the high melting points and poor thermal stability of ceramics present a formidable challenge. Traditional welding methods often fall short, but Vacuum Brazing has emerged as a superior alternative. This process capitalizes on the unique properties of both materials, creating strong and reliable Ceramic to Metal bonds.

While there are various methods for joining ceramics and metals, including mechanical joining and solid-state diffusion bonding, Vacuum Brazing offers a combination of performance, cost-effectiveness, and ease of implementation that is unmatched.

The process of Vacuum Brazing involves the use of a brazing filler metal that melts at a lower temperature than the materials being joined. In the case of Ceramic to Metal bonding, Active Metal Brazing with Ag-Cu-Ti powder as the filler metal is particularly effective. The active element, titanium, reacts with the ceramic surface, cleaning and activating it for a stronger bond.

For instance, when brazing Al2O3 ceramics with 304 stainless steel, metallized ceramic surfaces are prepared, and AgCu is used as the brazing filler metal. The Vacuum Brazing process ensures that the resulting joints can withstand high-temperature tests, demonstrating exceptional hermeticity and reliability.

The use of Active Metal Brazing in Vacuum Brazing allows for the achievement of shear strengths of up to 130 MPa in brazed joints. This highlights the significant potential of Vacuum Brazing in creating durable Ceramic to Metal connections that are suitable for a wide range of applications.

As research in this field progresses, Vacuum Brazing continues to evolve, offering ever-improving joint strength and versatility. It stands as a critical technology in material joining, pushing the boundaries of what is possible in the creation of Ceramic to Metal composite components.

Ceramic Cores in High Voltage Resistors: Engineering Excellence for Power Applications

High voltage resistors are essential components in electronic circuits where precision, reliability, and safety are paramount. Among the various types of materials used for high voltage resistors, ceramic cores stand out for their exceptional properties and suitability for demanding applications. Generally the high voltage resistor ceramic cores material is alumina ceramic and it can used as alumina ceramic heater.

Characteristics of Ceramic Cores
Ceramic cores used in high voltage resistors are typically composed of a blend of ceramic materials and metal oxides, carefully formulated to achieve specific electrical and mechanical properties. Key characteristics include:

High Dielectric Strength: Ceramic materials inherently offer high dielectric strength, allowing resistors to withstand high voltages without electrical breakdown or insulation failure.

High Stability: They provide excellent stability over a wide range of operating temperatures and environmental conditions, ensuring consistent performance in critical applications.

Low Temperature Coefficient: Ceramic cores can be engineered to have a low temperature coefficient of resistance (TCR), minimizing variations in resistance values due to changes in temperature.

Mechanical Robustness: Resistant to physical damage and stress, ceramic cores maintain structural integrity under mechanical load, vibrations, and thermal cycling.

Advantages of Ceramic Core High Voltage Resistors
Reliability: Ceramic cores contribute to the overall reliability of high voltage resistors by maintaining stable electrical characteristics over time, reducing the likelihood of failure or performance degradation.

Precision: They allow for precise control of resistance values and tolerance levels, critical for applications requiring accurate voltage division and current limiting.

Compact Design: Alumina Ceramic materials enable the production of compact resistors suitable for densely packed electronic assemblies, saving space and enhancing circuit design flexibility.

Wide Operating Temperature Range: High voltage resistors with ceramic cores can operate effectively across a broad temperature range, from extreme cold to high heat environments, making them versatile for diverse industrial and automotive applications.

Applications in Various Industries
Ceramic core high voltage resistors find extensive use across several industries:

Power Electronics: In power supplies, inverters, and converters, where reliable voltage regulation and current limiting are essential.

Medical Equipment: Used in high voltage power supplies for medical devices, ensuring safe and precise operation.

Industrial Automation: In motor controls, robotics, and industrial machinery where high voltage components must withstand rigorous operating conditions.

Telecommunications: Found in communication equipment, antennas, and transmission systems requiring stable performance in varying environmental conditions.

Manufacturing and Design Considerations
The manufacturing of ceramic core high voltage resistors involves advanced techniques such as precision mixing of ceramic powders, shaping, and firing at high temperatures to achieve the desired electrical and mechanical properties. Design considerations include selecting appropriate ceramic materials, electrode configurations, and protective coatings to optimize performance and longevity.

Ceramic cores play a critical role in the development of high voltage resistors, offering superior electrical properties, mechanical robustness, and reliability.As technology advances and demands for efficiency and reliability grow, ceramic core high voltage resistors continue to evolve, meeting the stringent requirements of today’s power electronics and industrial sectors.

Ceramic and Metal Medical X-Ray Tubes: The Future of Analytical Instruments Components

Innovacera Advanced Materials is a leading manufacturer of medical X-ray components, specializing in the production of a comprehensive range of products that combine the precision of metal with the exceptional properties of ceramics. Our expertise in Analytical Instruments Components is evident in the high-quality anodes, cathodes, X-ray tubes, and getter assemblies we produce. We leverage our advanced Ceramic-to-Metal Sealing technology to provide robust and reliable components that are tailored to meet the unique challenges of the X-ray market.

Our medical X-ray products are designed to seamlessly integrate various metal components with high-purity alumina (Al₂O₃) ceramics, which are known for their hermetic sealing properties. The use of Alumina X-ray power tube in our products ensures improved repeatability of focal spot positioning, longer tube life, and unmatched spectral purity. The flexibility in our design allows for customization to meet specific customer needs, while our consistent and repeatable manufacturing processes ensure cost-competitive production.

The hermetic Ceramic used in our components is a key factor in their reliability. It reduces the risk of seal leaks, offers thermal shock resistance, and is not limited by size constraints. The superior electrical performance of our components, which includes the use of hermetic Ceramic-to-Metal Sealing, allows for higher power and safety margin designs. Our innovative technologies extend the lifespan of X-ray tubes and highlight the many specific application benefits of combining ceramic and metal in our components.

We also offer custom solutions for other ceramic-to-metal components, such as feedthroughs and multi-pin headers, which are essential for Analytical Instruments Components that require precision and reliability.

For more information about our medical X-ray tubes and how our advanced technologies can benefit your applications, please contact us today.

How to protect mass spectrometry filament assembly?

The mass spectrometer filament, a critical component of analytical instruments, plays a pivotal role in generating an ion source within a high vacuum environment. The performance of this filament, often made from LaB6 Ceramics, directly impacts the sensitivity, resolution, and stability of the mass spectrometer. The LaB6 filament assembly, a type of filament assembly specifically designed for longevity and high performance, is essential for the reliable operation of mass spectrometry systems.

Both ends of the LaB6 filament assembly are connected to a high-voltage power supply, creating an electric field that facilitates ionization in the vacuum. In this environment, the metal atoms within the LaB6 filament are ionized, producing positive ions and electrons. These ions are accelerated by the electric field and interact with the filament surface, causing further ionization through collisions with surface atoms. This process generates a continuous supply of ions, forming an ion cloud that, when influenced by a magnetic field, separates ions of different masses, thus enabling mass spectrum analysis.

Given that the filament is a consumable, it may degrade over time, necessitating replacement. To protect the LaB6 filament assembly and prolong its service life, it is crucial to consider several factors that can accelerate filament damage.

The influence of oxygen
A leak in the mass spectrometer can introduce oxygen into the vacuum chamber, which, when combined with the filament’s operation, can significantly speed up the degradation process. Oxygen not only affects the filament but can also prematurely age the electron multiplier. To prevent this, it is advisable to check for air leaks using an Air/Water Tune before taking samples. Common leak points include the transmission line nut or the vent valve. Applying acetone to suspected leak points can help identify leaks by observing an increase in the abundance of m/z=58 ions.

Effect of solvents
Solvents pose another significant threat to the longevity of the filament. Particularly during liquid injections, large volumes of solvent can enter the mass spectrometer, potentially burning out a filament in normal operation. To mitigate this, setting a solvent delay time can be an effective strategy to protect the filament assembly.

In addition to these protective measures, the choice of filament assembly material is also critical. Tungsten (W) filament assembly, for instance, is known for its robustness and resistance to wear in certain applications. However, for applications requiring high analytical performance and longevity, LaB6 filament assembly remains a superior choice.

INNOVACERA, with its extensive expertise in the production and manufacturing of filament assemblies, including LaB6 Ceramics filament assemblies, stands ready to assist with your analytical instruments components needs. Should you require a high-quality LaB6 filament assembly or have any inquiries regarding the protection and maintenance of your mass spectrometry filament assembly, please do not hesitate to get in touch with us.

Properties and applications of silicon carbide ceramics

Silicon carbide ceramics is a kind of silicon carbide (SiC) as the main component of the ceramic material, with excellent mechanical properties at room temperature and high temperature mechanical properties, including high bending strength, excellent oxidation resistance, good corrosion resistance, high wear resistance and low friction coefficient. The high temperature strength of this material can be maintained to 1600 ° C, which is the best high temperature strength of known ceramic materials.

The following is a brief introduction to the properties and applications of silicon carbide ceramics

(1) Performance

Silicon carbide ceramics have the best oxidation resistance among carbides. However, between 1000 and 1140 ° C, the oxidation rate of SiC in the air is larger. It can be broken down by molten alkali.

Silicon carbide ceramics have good chemical stability, high mechanical strength and thermal shock resistance.

The volume resistivity of silicon carbide does not change much in the range of 1000~1500℃, and this characteristic can be used as a resistance heating element material. Silicon carbide heating resistance itself can also be called thermistor or semiconductor resistance. The resistivity of different types of silicon carbide thermistors varies with temperature.

(2) Application

Silicon carbide ceramics are widely used in various industrial fields, and its uses are as follows:

Industrial	Working environment	Application	Principal advantage
oil industry	High temperature, high hydraulic pressure, grinding	Nozzles, bearings, seals, valves	wear-resisting
chemical industry	strong acid, strong alkali	Seals, bearings, pump parts, heat exchangers	Wear resistance, corrosion resistance, air tightness
chemical industry	high temperature oxidation	Gasification pipeline, thermocouple sleeve	High temperature corrosion resistance
Cars & Planes	Engine combustion	Burner components, turbocharger rotor	Low friction, high strength, low inertial load
Cars & Engines	engine oil	Valve series element	Low friction, wear resistance
Machinery, Mining	grinding	Borax nozzle, lining, pump parts	wear-resisting
paper industry	pulp, waste liquid	Seal, casing, bearing, forming plate	Wear resistance, corrosion resistance, low friction
heat treatment smelting steel	high-temperature gas	Thermocouple bushing, radiation tube, heat exchanger, combustion element	Wear resistance, corrosion resistance, air tightness

Innovacera has been focusing on providing customers with ceramic material solutions for many years. Including but not limited to silicon carbide ceramic parts customization, if you have any needs, please feel free to contact us.

Introduction of AMB Substrate Technology

AMB (Active Metal Brazing) is a method of sealing ceramics and metals developed on the basis of DBC technology.

Compared with traditional DBC substrates, ceramic substrates prepared by AMB process not only have higher thermal conductivity and better copper layer bonding, but also have advantages such as lower thermal resistance and higher reliability. In addition, because its processing process can be completed in one heating, it is easy to operate, has a short time cycle, good sealing performance and a wide range of applications for ceramics, so this process has developed rapidly at home and abroad and has become a commonly used method in electronic devices.

AMB process description

AMB is to add active elements to the brazing material, form a reaction layer on the ceramic surface through chemical reaction, improve the wettability of the brazing material on the ceramic surface, so that the ceramic and the metal can be directly brazed and sealed.

Usually, the active element content is between 2% and 8% with good activity. When the content of active elements is too high, the brittleness of the brazing material will increase, thereby reducing the strength of the sealing surface. When the content of active elements is too low, the wettability of the brazing material to the ceramic will decrease, making the sealing difficult to complete.

Three kinds of ceramic materials of AMB

The ceramic lining produced by AMB process is mainly used in power semiconductor modules as the substrate of silicon-based and carbide-based power chips. At present, the mature AMB ceramic substrates are mainly: alumina, aluminum nitride and silicon nitride substrates.

At present, Al2O3 copper-clad ceramic substrates are mainly used in low-power heat dissipation devices such as LEDs, AlN and Si3N4 copper-clad ceramic substrates are mainly used in high-power IGBT modules such as high-speed rail and wind power generation.

1. Al2O3 ceramic substrate

Al2O3 ceramics are widely available and have the lowest cost. They are the most cost-effective AMB ceramic substrates with the most mature process. They have excellent characteristics such as high strength, high hardness, high temperature resistance, corrosion resistance, wear resistance and good insulation performance.

However, due to the low thermal conductivity and limited heat dissipation capacity of alumina ceramics, AMB alumina substrates are mostly used in fields with low power density and no strict requirements on reliability.

2. AlN ceramic substrate

AlN ceramic has better properties than traditional Al2O3 and BeO substrate materials due to its high thermal conductivity (theoretical thermal conductivity 319 W/(m·K)), low dielectric constant, thermal expansion coefficient matching that of single crystal silicon, and good electrical insulation performance, making it an ideal material for circuit substrate packaging in the microelectronics industry.

At present, aluminum nitride ceramic substrates (AMB-AlN) using the AMB process are mainly used in high-voltage and high-current power semiconductors such as high-speed rail, high-voltage converters, and DC power transmission. However, due to its relatively low mechanical strength, the high and low temperature cycle impact life of AMB-AlN copper-clad substrates is limited, which limits its application range.

3. Si3N4 ceramic substrate

AMB-SiN ceramic substrates have high thermal conductivity (>90W/(m·K)), thick copper layer (up to 800μm), and high heat capacity and heat transfer. In particular, when a thicker copper layer is welded to a relatively thin AMB-SiN ceramic, it has a higher current carrying capacity and better heat transfer.

In addition, the thermal expansion coefficient of AMB-SiN ceramic substrate (2.4ppm/K) is close to that of SiC chip (4ppm/K), which has good thermal matching and is suitable for reliable packaging of bare chips.

At present, AMB-SiN ceramic substrate is the preferred substrate material for application scenarios such as new energy vehicles, photovoltaic inverters, wind turbines and high-voltage DC transmission devices that require high reliability, high heat dissipation and partial discharge.

According to statistics, the ceramic substrates used for power semiconductors above 600V are mainly DBC and AMB processes, among which AMB silicon nitride substrates are mainly used for electric vehicle (EV) and hybrid vehicle (HV) power semiconductors, and AMB aluminum nitride substrates are mainly used for high-voltage and high-current power semiconductors such as high-speed rail, high-voltage converters, and DC power transmission.

Conclusion
The market demand for AMB ceramic substrates has increased, among which the rapid growth of electric vehicles, the accelerated installation of SiC, and the rapid growth of new energy vehicles are the main driving factors.

If you have any question about the AMB substrate, welcome to contact us at sales@innovacera.com.

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