Category: thin film

3 Factors of Target Quality Influence Large-area Coating

Most modern buildings have begun to use large areas of glass for lighting, and its biggest advantage is that it can bring us brighter light and a wider view. However, since the heat energy transmitted through the glass is much higher than the surrounding walls, the energy consumption of the entire building increases significantly. In order to solve this problem, people have begun to study and apply large-area Low-E glass.

Low-E glass is commonly used in building construction because of its ability to save energy, control light, and for aesthetics. The sputtering target material is one of the essential components for making low-e glass, so this article will introduce 3 factors of target quality that influence large-area coating of low-E glass.

The shape of the target materials

For large-area coating, commonly used targets include planar targets and rotatory targets according to their shapes. The shape of the target affects the stability and film properties of the magnetron sputtering coating, as well as the utilization rate of the target. Therefore, the coating quality and production efficiency can be improved by changing the shape design of the target, and the cost can be saved.

planar targets and rotatory targets
Planar targets and rotatory targets

Relative density & porosity of the target

The relative density of the target is the ratio of the actual density to the theoretical density. The theoretical density of a single-component target is the crystal density, and the theoretical density of an alloy or compound target is calculated from the theoretical density of each component and its proportion in the alloy or mixture.

If the target material is loose and porous, it will absorb more impurities and moisture, which are the main pollution sources in the coating process. These impurities will hinder the rapid acquisition of high vacuum, easily lead to electrical discharge during the sputtering process, and even burn out the target. Find high-quality target material here: https://www.sputtertargets.net/

Target grain size and crystallographic direction

For targets of the same composition, the one with the smaller grain size has a faster deposition rate. This is mainly due to the fact that grain boundaries are more vulnerable to attack during the sputtering process, and the more grain boundaries, the faster the film formation.

In addition, the grain size also affects the quality of the film formation. For example, in the production process of Low-E glass, NiCr thin-film is used as the protective layer of the infrared reflection layer Ag, and its quality has a great influence on the coating products. Since the extinction coefficient of the NiCr film is relatively large, it is generally plated very thinly (about 3nm). If the grain size is too large and the sputtering time is short, the compactness of the film will be poor, the protective effect of the Ag layer will be reduced, and the coating product will be oxidized and removed.

Conclusion

The shape of the target mainly affects the utilization rate of the target material, and a reasonable size design can improve the utilization rate of the target material and save costs. The smaller the grain size, the faster the coating rate and the better the uniformity. The higher the purity and density, the lower the porosity, the better the quality of the film formation, and the lower the probability of slag removal by discharge.

Electron Beam Deposition for Film Coating

Introduction

Electron beam deposition is a form of physical vapor deposition (PVD) in which the target anode material is bombarded with a stream of electrons generated by a tungsten filament. Electron beam thin film deposition techniques are widely used in R&D as well as in mass production applications.

Electron beam deposition is performed in a vacuum, typically starting the process at levels below 10-5 Torr. Once a suitable vacuum is reached, a tungsten filament in the electron beam source emits a stream of electrons. This electron beam can be generated in various ways, including thermionic emission, field electron emission, or ion arc source, depending on the design of the source and associated power supply.

In all cases, the negatively charged electrons are attracted to the positively charged anode material. The generated electron beam is accelerated to high kinetic energy and directed towards the material to be deposited on the substrate. This energy is converted into heat by interacting with the atoms of the evaporated material.

The purpose of generating a stream of electrons in an electron beam source is to heat the deposited material to a temperature above a vapor pressure threshold at a given background pressure. The vapor stream is then condensed onto the surface of the substrate.

Schematic representation of electron beam evaporation system depicting various parts.
Schematic representation of electron beam evaporation system depicting various parts.. Mohanty, P. & Kabiraj, Debdulal & Mandal, R.K. & Kulriya, Pawan Kumar & Sinha, Ask & Rath, Chandana. (2014). Evidence of room temperature ferromagnetism in argon/oxygen annealed TiO2 thin films deposited by electron beam evaporation technique. Journal of Magnetism and Magnetic Materials. 355. 240–245. 10.1016/j.jmmm.2013.12.025.

Deposition Rate

As with all thermal evaporation systems, the electron beam deposition rate depends on the temperature of the material being deposited and the vapor pressure (physical constant) of that material. For elemental materials, there is a fixed vapor pressure for any particular background pressure (vacuum) and material temperature. However, for alloys or composites, there may be different partial pressures associated with each component.

Compared with Sputter Coating

Unlike sputter deposition, where individual atoms arrive at the substrate surface with very high velocity and momentum, the thermally generated vapor stream arrives at the substrate surface at a considerably lower velocity, but a much greater velocity. In other words, e-beam deposition rates can be orders of magnitude greater than sputter deposition rates, making e-beam coatings very beneficial for high volume production or thick film requirements. One disadvantage, however, is that the material tends to condense directly on the substrate surface due to the different kinetic energy of the arriving species during electron beam evaporation than that of the sputtered species. In contrast, atoms of sputtered materials tend to penetrate several atomic layers (or more) to the substrate surface before losing momentum and then establishing cohesive bonds in nucleation structures and film growth. Thus sputtered films tend to provide better adhesion properties than thermally evaporated materials.

For more information, please visit https://www.sputtertargets.net/.

Metal Molybdenum Target Used in Mobile Phone LCD Screen

Nowadays, mobile phones have become the most indispensable thing for the masses. Mobile phone displays are also becoming more and more high-end, such as full-screen designs, small bang designs, and so on.

One of the most important steps in making a mobile phone LCD screen is thin film coating, using magnetron sputtering to sputter the molybdenum target onto the liquid crystal glass to form a Mo thin film. Molybdenum thin films have the advantages of high melting point, high electrical conductivity, low specific impedance, good corrosion resistance and good environmental performance. Compared with the chromium film, the specific impedance and film stress of the molybdenum film are only half of that.

As an advanced film material preparation technology, sputtering has two characteristics of “high speed” and “low temperature”. It concentrates ions into a high-speed ion stream in a vacuum to bombard a solid surface. The kinetic energy exchange between the ions and the atoms on the solid surface causes the atoms on the solid surface to leave the target and deposit on the surface of the substrate to form a nano (or micro) film. The bombarded solid is a material for depositing a thin film by sputtering, which is called a sputtering target.

mobile phone lcd screen

In the electronics industry, molybdenum sputtering targets are mainly used for flat panel displays, electrodes and wiring materials for thin film solar cells, and barrier materials for semiconductors. These are based on its high melting point, high electrical conductivity, low specific impedance, good corrosion resistance, and good environmental performance.

Molybdenum used in components of LCDs can greatly improve the brightness, contrast, color, and life of the LCD. One of the major applications for molybdenum sputtering targets in the flat panel display industry is in the TFT-LCD field.

In addition to the flat panel display industry, with the development of the new energy industry, the application of molybdenum sputtering targets on thin film solar photovoltaic cells is also increasing. The molybdenum sputtering target mainly forms a CIGS (Copper Indium Gallium Selenide) thin-film battery electrode layer by sputtering. Among them, molybdenum is at the bottom of the solar cell, and as a back contact of the solar cell. It plays an important role in the nucleation, growth, and morphology of the CIGS thin film crystal.

For more information, please visit https://www.samaterials.com/.

Solar Thin Film and Its Technical Advantages

Thin-film solar cells refer to thin films with thicknesses ranging from a few nanometers to tens of microns attached to the solar surface, which make thin-film cells lighter in weight. Thin-film solar cells are used in building-integrated photovoltaics as translucent photovoltaic glass materials that can be laminated to windows.

As a second-generation solar technology, thin-film technology is more affordable than the traditional first-generation c-Si technology, but is less efficient. Therefore, in recent years, people have also paid more attention to the development of sputtering materials and thin film coating technology, and are committed to improving the efficiency of thin film technology. And now it has improved significantly. Laboratory cell efficiencies for CdTe and CIGS are now over 21%, better than polysilicon, the main material currently used in most solar photovoltaic systems. And the life expectancy of thin-film solar cells is also extended to 20 years or more.

Thin film solar cells are made by depositing one or more thin layers or thin films of photovoltaic materials on a substrate such as glass, plastic or metal. In the deposition process, the coating source material used are usually sputtering targets or evaporation materials. Commonly used thin-film solar cell categories include cadmium telluride (CdTe) thin films, copper indium gallium selenide (CIGS) thin films, and gallium arsenide (GaTe) thin films.

The target materials corresponding to the three thin films mentioned above are important materials for the thin film coating of solar cells. Among them, cadmium telluride targets account for 50% of the solar market. On a life cycle basis, CdTe PV has the smallest carbon footprint, lowest water usage, and shortest energy payback time of all solar technologies. With an energy payback period of less than a year, CdTe can reduce carbon emissions faster without short-term energy shortages.

The CIGS sputtering target is composed of four metal elements, namely copper (Cu), indium (In), gallium (Ga) and selenium (Se), and it is also one of the representatives of commonly used targets in the solar industry. CIGS thin film has the advantages of strong light absorption, good power generation stability and high conversion efficiency, which can enable solar cells to generate electricity for a long time during the day and generate a large amount of electricity. CIGS has great advantages in photovoltaic building-integrated applications. At the same time, with the improvement of CIGS conversion efficiency, the self-sufficiency rate of CIGS as a photovoltaic building power supply built with glass curtain walls is also increasing.

GaAs thin-film solar cells have an efficiency of up to 28.8%, which is considered the highest efficiency of all thin films. Gallium arsenide is also resistant to damage from moisture, radiation and UV light. These properties make GaAs thin films an excellent choice for aerospace applications with increased UV and radiation.

For more information, please visit https://www.sputtertargets.net/.

Seven Sputtering Targets and Their applications

Tantalum is used as a barrier layer on silicon wafers for semiconductor production, and tantalum is used in all modern electronic products. Mobile phones, DVD and Blu-ray players, laptops, etc. Car electronics and even game consoles contain tantalum.

Niobium is commonly used in electronic products and its properties are similar to tantalum. Niobium has corrosion resistance due to its oxide film and is considered a superconductor.

Titanium has the characteristics of light weight and corrosion resistance, and can be used in various conventional products including watches, notebook computers and bicycles. Titanium is commonly used for wear resistance and aesthetic design, but can also be used for semiconductor and optical coatings.

Read more: Everything You Need to Know About Titanium Sputtering Target

Tungsten film is a decorative coating, due to its thermal, physical and mechanical properties (such as high melting point
And thermal conductivity) and widely used.

Molybdenum has a lower density and a consistent price, and can be used to replace tungsten. It is usually used to coat solar panel cells.

black and white solar panels

It is often used as an insulator for semiconductors, as well as surface hardness and protective layer. As an element with a high dielectric constant, it can improve the performance of certain electronic devices.

This target material is most commonly used in the production of silicon solar cells.

Applications of High Purity Copper Sputtering Target

The copper sputtering target is a coating material made of metallic copper, which is suitable for DC bipolar sputtering, three-pole sputtering, four-stage sputtering, radio frequency sputtering, counter target sputtering, ion beam sputtering, and magnetron sputtering, etc. It can be applied to manufacture reflective films, conductive films, semiconductor films, capacitor films, decorative films, protective films, integrated circuits, displays, and etc. Compared with other precious metal sputtering targets, the price of copper targets is lower, so the copper target is the preferred target material under the premise of satisfying the function of the film layer.

Copper sputter targets are divided into the planar copper target and rotary copper target. The former is sheet-shaped, with round, square, and the like; the latter is tubular, and the utilization efficiency is high.

planar and rotory copper sputtering target

High-purity copper sputter targets are mainly used in electronics and information industries, such as integrated circuits, information storage, liquid crystal displays, laser memories, electronic control devices, etc.; they can be applied to the field of glass coating; they can also be applied to wear-resistant materials, high-temperature corrosion resistance, high-end decorative supplies and other industries.

Information storage industry: With the continuous development of information and computer technology, the demand for recording media in the world market is increasing, and the corresponding target media for recording media is also expanding. Related products include hard disks, magnetic heads, and optical disks. (CD-ROM, CD-R, DVD-R, etc.), a magneto-optical phase-change optical disc (MO, CD-RW, DVD-RAM).

Integrated circuit industry: In the field of semiconductor applications, sputtering targets are one of the main components of the world target market. They are mainly used for electrode interconnect film, barrier film, contact film, optical disk mask, capacitor electrode film, and resistive film, etc.

Flat-panel display industry: Flat panel displays include liquid crystal displays (LCDs), plasma displays (PDPs), and the like. At present, LCD is the main market in the flat panel display market, and its market share exceeds 85%. LCD is considered to be the most promising flat display device and is widely used in notebook monitors, desktop monitors and high definition televisions. The manufacturing process of the LCD is complicated, in which the reflective layer, the transparent electrode, the emitter and the cathode are all formed by a sputtering method, and therefore, the sputtering target plays an important role in the manufacture of LCD.

For more information, please visit https://www.sputtertargets.net/.

Indium: Stable Demand in Thin Film Solar Industry

With the full arrival of the mobile energy era, the thin film solar industry grows explosively. Thin-film solar chips are light, thin, and flexible. They can be embedded in various types of carriers like Intel chips, from urban skyscrapers to neighborhood roofs, or parasols on the street, and cars running on the road. They have turned traditional products into “power generation bodies”, enabling energy sharing and free use.

Indium

Indium is one of the basic raw materials for the manufacture of thin film solar cells. Indium, atomic number 49, was discovered in 1863 by the German chemist H. Richter in zinc concentrate. Indium is silvery white and has a light blue color. The texture is very soft and can be scored with nails. In nature, indium minerals are dispersed in trace amounts in other minerals. The distribution of indium in the earth’s crust is relatively small, 1/8 of gold and 1/50 of silver. So far, no single or indium-based natural indium deposit has been found. Therefore, indium resources, in people’s impression, are scarce and difficult to mine, so that there is concern about whether there will be shortages and unstable prices of the precious metal.

Luckily, it is optimistic that the industry has said that with the improvement of mining technology, drilling technology, purification technology and recycling technology, more and more indium resources can be used. Therefore, even if the output of copper indium gallium selenide (CIGS) increases explosively in the next few years, it is difficult to affect the supply and demand of indium.

CIGS solar cell

CIGS solar cellIn the future, the copper indium gallium selenide film industry will enter a period of low-cost and high-speed development, and the thin-film solar market will be fully opened. As the photovoltaic industry continues to evolve, reducing power generation costs is a continuing goal. In this context, reducing the amount of precious indium through technical routes is a cost-reduction method that many companies are actively exploring.

At present, some companies have developed a more reliable solution to reduce the amount of indium used in copper-indium-gallium-selenide modules: developing new plasma-spray target technology, reducing the loss in sputtering target coating, reclaiming indium on residual targets, and etc. In addition, by appropriately increasing the composition of gallium or thinning the battery film layer in the copper indium gallium selenide battery, the amount of indium can also be effectively reduced.

The industry produces metal indium by purifying waste zinc and waste tin, and the recovery rate is about 60-70%. From this calculation, based on the proven reserves, the increase in recoverable amount and the indium recovery rate, the currently available indium is about 15,000 tons to 18,000 tons. If all of these indiums are used to produce copper indium gallium selenide batteries, it can produce 1,800 GW, and even if only one-tenth of the amount is used, it can produce 180 GW. In conclusion, in terms of current copper indium gallium selenide production capacity, indium resources are still very rich.

For more information about thin film coating, please visit https://www.sputtertargets.net/.

 

Thinning and Coating Process of Mobile Phone Cover Glass

According to the needs of various terminal applications, glass cover panels require various optical glass processing processes such as cutting, edging, drilling, polishing, thinning, chemical strengthening, printing, laser engraving and coating. Today we will introduce the thinning and coating of mobile phone cover glass, which are the most important parts of the whole manufacturing process.

Cover glass thinning process

The glass mentioned in this article is not the 3mm, 5mm, 8mm or even 10mm glass for civil use, but the cover glass for electronic products such as smartphones and tablet computers. Among the glasses currently on the market, the thinnest is 0.15 mm. There is a special thinning process that reduces the thickness of the glass.

Since Steve Jobs started using Corning Gorilla Glass for his iPhones, there emerges a new component for electronic products—cover glass. At the same time, the pursuit of thinner and lighter in the industry is also urging glass manufacturers to make changes to make thinner cover glass.

iPhone cover glass
iPhone cover glass

Currently, the thinnest glass of gorilla can be made 0.4mm, and the Asahi Glass can make 0.2mm glass. In general, people’s expectations for cover glass are nothing more than two:

1. Reduce the space occupied by the glass.

2. Make the glass cover a certain flexibility.

Mobile phone cover glass thinning process

There are not many processes for glass cover thinning: pre-cleaning—etching and thinning—–secondary cleaning——-grinding (single or double sided)—–post-cleaning—–check the package

Pre-cleaning: Remove the stain on the surface of the glass cover. It is one of the key steps affecting the effect of thinning.

Etching and thinning:  using acid and alkali to etch the glass cover achieve the purpose of thinning. The conditions and parameters (time, potash ratio, temperature, etc.) vary from manufacturer to manufacturer, which is the technical secret of the manufacturer.

Secondary cleaning: Clean the residue of the glass cover.

Grinding: To obtain a bright, flat surface. It is one of the key processes for appearance assurance and thickness tolerance control.

Post-cleaning: Clean the remaining grinding powder.

Check the packaging: The standard for the appearance of the glass is different depending on the requirements of the customer.

Mobile phone cover glass thinning treatment

1, multiple pieces of upright soak

2, waterfall flow processing

3, single piece vertical spray

Cover glass coating process

At present, vacuum magnetron sputtering coating technology is a widely used thin film deposition technology. The continuous development of sputtering technology and the exploration of new functional films have enabled the application of magnetron sputtering coating technology to be extended to many productions and scientific research fields.

magnetron sputtering system
magnetron-sputtering-system

magnetron sputtering coating applications

In the field of microelectronics, as a non-thermal coating technology, magnetron sputtering coating technology is mainly applied to materials that are not suitable for chemical vapor deposition or metal organic chemical vapor deposition. Moreover, using magnetron sputtering can obtain a large-area uniform film.

Magnetron sputtering technology is also used in optical films such as antireflection glass, low emissivity glass and transparent conductive glass. In the production of transparent conductive glass, the ITO conductive glass prepared by sputtering has an average transmittance of 90% or more in the visible light range.

In the modern machining industry, the use of magnetron sputtering technology to produce surface functional films, super hard films and self-lubricating films can effectively improve surface hardness, composite toughness, wear resistance and high temperature resistance and chemical stability, thus improve the service life of coated products.

In addition, magnetron sputtering coating technology also plays an important role in the research of high temperature superconducting thin films, ferroelectric thin films, giant magnetoresistive thin films, thin film luminescent materials, solar cells, and memory alloy thin films.

Magnetron sputtering coating advantages

Magnetron sputtering coating technology has become one of the main technologies of the industrial coating due to its remarkable advantages:

(1) Simple operation and easy control. In the coating process, if the sputtering conditions such as working pressure and electric power are relatively stable, the deposition rate is relatively stable.

(2) The deposition rate is high. When depositing most of the metal, especially the high melting point metal and oxide, such as tungsten, aluminum TiO2 and ZrO2 film, it has a high deposition rate.

(3) Low temperature of the substrate. Compared to two-pole sputtering or thermal evaporation, magnetron sputtering reduces the heating of the substrate, which is quite advantageous for achieving the sputter coating of the fabric.

(4) The sputtered film is strong. The sputtered film has excellent adhesion to the substrate and its mechanical strength is also improved.

(5) The sputtered film is dense and uniform. From the photomicrograph, the surface morphology of the sputtered film is fine and uniform.

(6)The sputtered films all have excellent properties. For example, sputtered metal films generally achieve good optical properties, electrical properties, and certain special properties.

(7) Easy to mass produce. The magnetron source can be expanded as required, so large-area coatings are achievable. In addition, sputtering can work continuously, and the coating process is easy to control automatically, so that the industrial assembly line can be realized.

(8) Environmentally friendly. Conventional wet plating produces waste liquid, waste residue, and exhaust gas, causing serious pollution to the environment. The magnetron sputtering coating method has high production efficiency while does not cause environmental pollution.

Please visit https://www.sputtertargets.net/ for more information.

How to make the phone case of gradient color like Huawei P20?

Gradient color is popular in 2018

It’s overwhelming how many smartphone models are currently available on the market today.  However, as for the color of the phone, what get are the same old black, white, silver and gray, in glossy or matte.

Well, recently an exciting new trend has emerged. The Huawei P20 series let people see the optimal color design and professional photography. A few months ago, Huawei launched the P20 in Twilight, and the dual-tone gradient inspired by the Aurora Borealis made people feel excited.

Huawei P20
Huawei P20

Before that, HTC also introduced the two-tone gradient scheme. Although it does not offer the popular Twilight color scheme, it does bring us a few appealing options with its latest flagship device.

HTC U11
HTC U11

Samsung has also jumped on board the gradient crazy. The Korean tech giant has unveiled a new version of its Galaxy A9 Star in China which features a sleek purple gradient.

Galaxy A9 Star2
Galaxy A9 Star2

Well, these are just a few examples to show that gradient color is the fashion of the year 2018. Are you curious about how to achieve this kind of gradient color? Is it difficult?

Film coating-Physical vapor deposition

Actually, all the color of the shell is about film coating. A cellphone is made from a variety of metals, with the most common being aluminum alloys, lightweight materials commonly found in the phone case. And the film coating is to apply a colored film on the phone case.

Physical vapor deposition is the most widely used film coating technology. Under vacuum conditions, the surface of the material (usually referred to as the sputtering targets or evaporating pellets) is vaporized into gaseous atoms by physical methods, and is then deposited on the surface of the substrate to form a thin film. The main methods of physical vapor deposition include vacuum evaporation, sputtering coating, plasma coating, ion plating, and molecular beam epitaxy.

How to coat the gradient color

PVD can coat gold, brass, rose gold, silver white, black, smoky, copper, brown, purple, blue, burgundy, bronze and other colors on stainless steel, copper, zinc alloy and other metals. There are many choices and the price is affordable, compared to pure gold or other pure metals. (PVD Coating Materials.pdf) You can refer to our previous article for more information: Introduction to PVD Coatings.

By controlling the parameters of different targets and thickness of the deposited film, the film exhibits different colors (the gradation colors mentioned above) under the reflection, refraction and interference of light. Specifically, in the plating furnace space, bombard a specific sputtering target with ultra-high speed electrons; use a certain mask to cover a part of the ion cloud so that only the other part of the ion cloud can be attached to the substrate and forms a very thin layer of nano-plating; control the thickness of the coating to form a nanometer thickness difference; then spray the background color.

For more information, please visit https://www.sputtertargets.net/.

Introduction to PVD Coatings

What is PVD coating technology

PVD, or physical vapor deposition, is an advanced surface treatment technology widely used in the world. Under a vacuum condition, utilize the gas discharge to separate the gas or the evaporated substance, then accelerate the gas ion or the evaporated atoms to bombard the substrate and deposit a film. PVD film has fast deposition speed as well as strong adhesion, good diffraction, and wide application range.

PVD coating colors

PVD can coat gold, brass, rose gold, silver white, black, smoky, copper, brown, purple, blue, burgundy, bronze and other colors on stainless steel, copper, zinc alloy and other metals. There are many choices and the price is affordable, compared to pure gold or other pure metals. (PVD Coating Materials.pdf)

PVD Coating Materials and Their Characteristics
PVD Coating Materials and Their Characteristics

Applications

PVD technology is widely used in the processing of door and window hardware, lamps, jewelry, handicrafts, and other decorative products.

PVD is now quite popular in the hardware field, and many of the world’s leading hardware manufacturers have begun to develop PVD products and mass production.

PVD for molds and precision parts

In recent years, PVD coating technology has been applied more and more in the work surface strengthening treatment of molds. Its outstanding advantages are that it can effectively improve the service life of the mold, and at the same time reduce the coating temperature to about 250 °C ~ 500 °C, which can reduce the deformation of the workpiece. The PVD composite coating has excellent performance and has potential applications that cannot be underestimated. One of the main applications of PVD technology in the mold industry is TiN coating.

PVD & CVD

There are currently two coating methods commonly used in production: physical vapor deposition (PVD) and chemical vapor deposition (CVD). The former has a deposition temperature of 500 ° C and a coating thickness of 2 to 5 μm; the latter has a deposition temperature of 900 ° C to 1100 ° C, a coating thickness of 5 to 10 μm, and the device is simple and the film is uniform.

Previously, most cemented carbides are coated by CVD. However, since the deposition temperature is high, the cemented carbide coated by the CVD method,  a brittle decarburization layer (η phase) is easily formed between the coating layer and the substrate, resulting in brittle fracture of the blade. In the past decade or so, with the advancement of coating technology, the cemented carbide can also adopt the PVD method.

Development of cemented carbide coatings

Coating refers to the application of a thin layer of wear-resistant, refractory metal or non-metallic compound on the substrate of cemented carbide or high-speed steel by vacuum evaporation and sputtering.

A good coating material is required to have high hardness, good wear resistance, stable chemical properties, no chemical reaction with the workpiece material, heat and oxidation resistance, low friction factor, and strong adhesion to the substrate. However, a single coating material is difficult to meet the above requirements. Therefore, the development of cemented carbide coating materials has entered a new stage of thick film, composite film and multi-component coating.

The most mature and widely used cemented carbide coating material is TiN, but the bonding strength of TiN and the substrate is less than that of TiC. TiC coatings have high hardness and wear resistance, and good oxidation resistance, but they are brittle and not resistant to impact. Both of these kinds of coatings have advantages and disadvantages, and TiCN combines their merits.

TiCN coating
TiCN coating

Combine 1)the newly developed multi-component, ultra-thin TiCN, TiAlN coating, 2)TiC, TiN, Al2O3 coatings, and 3)a new anti-plastic deformation matrix can significantly improve the toughness, bond strength of the coating to the substrate, and wear resistance of the coating. At present, the technology of coating diamond film on the cemented carbide substrate is successfully realized, and the performance of the tool is comprehensively improved.

TiAlN, CrN, and TiAlCrN are also new materials for cemented carbide coatings developed in recent years. The chemical stability and oxidation resistance of TiAlN are good. Compared with TiN, the tool life can be improved by 3 to 4 times when processing high alloy steel, stainless steel, titanium alloy and nickel alloy with TiAlN.

CrN is a titanium-free coating with good chemical stability and no sticking. It is suitable for cutting titanium and titanium alloys, copper, aluminum and other soft materials.

TiAlCrN is a gradient structure coating, which not only has high toughness and hardness, but also has a small friction factor. It is suitable for milling cutters, hobs, taps and other tools, and its cutting performance is obviously better than TiN.

In addition to the above new coatings, there are some coatings with specific functions, such as MoS2, DLC lubricated coatings, which have a small friction factor (0.05) and are suitable for coating tools such as taps and drills to improve chip evacuation performance.

For more information, please visit https://www.sputtertargets.net/.