Yearly Archives: 2024

　　Choosing which surface treatment to use is a problem that every designer faces. There are many types of surface treatments to choose from, and not only should the economy and practicality of the design be considered, but also the processability of the assembly and even environmental protection requirements should be taken into consideration. The following is a brief introduction to some commonly used coatings for fasteners based on the above principles for reference.among non standard fasteners It has given great spiritual support to entrepreneurs, and more entrepreneurs will contribute to this industry in the future. https://jieruifasteners.com/

　　1. Electrogalvanizing

　　Electrogalvanizing is the most commonly used coating for commercial fasteners. It is relatively cheap and looks good. Common colors include black and military green. However, its anti-corrosion performance is average, and its anti-corrosion performance is the lowest among zinc plating (coating) layers. Generally, the neutral salt spray test of electrogalvanizing is within 72 hours. Special sealants are also used to make the neutral salt spray test reach more than 200 hours, but the price is expensive, which is 5 to 8 times that of general galvanizing. The torque-preload consistency of electrogalvanized fasteners is poor and unstable, and is generally not used for connections in important parts. In order to improve the torque-preload consistency, the method of applying lubricating substances after plating can also be used to improve and improve the torque-preload consistency.

　　2. Phosphating

　　A basic principle Phosphating is cheaper than galvanizing, but its corrosion resistance is worse than galvanizing. Oil should be applied after phosphating, and its corrosion resistance is greatly related to the performance of the oil applied. For example, after phosphating, applying general anti-rust oil, the neutral salt spray test is only 10 to 20 hours. Applying high-grade anti-rust oil can last for 72 to 96 hours. But its price is 2 to 3 times that of general phosphating oiling.

　　There are two common types of non-standard fasteners phosphating, zinc phosphating and manganese phosphating. Zinc phosphating has better lubrication performance than manganese phosphating, and manganese phosphating has better corrosion resistance and wear resistance than galvanizing. Its operating temperature can reach 225 degrees to 400 degrees Fahrenheit (107 to 204 degrees Celsius). Especially for the connection of some important parts. Such as the connecting rod bolts and nuts of the engine, cylinder heads, main bearings, flywheel bolts and wheel bolts and nuts. Phosphating high-strength bolts can also avoid hydrogen embrittlement problems, so in the industrial field, bolts above grade 10.9 are generally treated with phosphating surface treatment.

　　3. Oxidation blackening

　　Blackening + oiling is a very popular coating for industrial fasteners because it is the cheapest and looks good before the oil runs out. Since blackening has almost no anti-rust ability, it will rust quickly after oiling. Even in the presence of oil, the neutral salt spray test can only reach 3 to 5 hours.

　　4. Electroplating cadmium

　　Cadmium coating has good corrosion resistance, especially in marine atmospheric environment, its corrosion resistance is better than other surface treatments. The waste liquid treatment cost in the process of electroplating cadmium is high, and its price is about 15~20 times that of electroplating zinc. Therefore, it is not used in general industries and is only used in some specific environments. For example, it is used for non-standard fasteners for oil drilling platforms and HNA aircraft.

　　As the pressure of life continues to increase, more and more people are beginning to pay attention to sleep problems. Well-known sleep experts, including Wang Gongquan, Zhang Jing, etc., recommend memory pillows (slow rebound pillows) to improve the quality of sleep. But many people still don’t understand why memory pillows have such effects, and how these pillows are designed and manufactured? In this article, we will introduce the principle and manufacturing process of memory pillows in detail, and discuss whether it really works.In the eyes of peers, travel pillow memory foam It has good qualities that people covet, and it also has many loyal fans that people envy. https://tainengjikang.com/

　　Are memory pillows (slow rebound pillows) really effective? What is the principle?

　　1. The principle of memory pillow

　　Memory pillow, also known as slow rebound pillow, is made of a highly elastic foam material that can appropriately disperse the load according to the weight and heat of the human head, and can also make adaptive adjustments to the curve of the head. When you press your head on the pillow, it will sense the contour of your head and gradually adapt to the shape of your head. When you leave the pillow, the pillow slowly rebounds to its original shape to improve comfort and support. Memory pillows usually consist of three parts: outer cover or pillowcase, liner or filler and memory foam.

　　Are memory pillows (slow rebound pillows) really effective? What is the principle?

　　2. Manufacturing process of memory pillow

　　1. Raw material preparation: The main raw material required for the production of memory pillow is polyurethane foam material, and other ingredients are also required, such as catalysts, detergents, stabilizers, etc.

　　2. Foaming: Foaming is a key step in the manufacture of memory pillows. After the raw materials are mixed at a certain temperature, they are pumped into the mold for foaming. During foaming, multiple parameters such as temperature, pressure, and time are strictly controlled. When the foam is formed, it needs to be processed with an oven or other equipment to ensure that the foam has a smooth surface and is not sticky.

　　3. Cutting: After the foaming is completed, the industry personnel use automated equipment to cut the foam into memory pillow blocks of various sizes and shapes. During this process, the size of each block needs to be carefully controlled to ensure that they meet the design requirements.

　　4. Packaging: Finally, the manufacturer puts the memory pillow blocks into the corresponding covers, usually fiber nylon or ribbed cloth covers, to make a whole.

　　Are memory pillows (slow rebound pillows) really effective? What is the principle?

　　3. Advantages and Disadvantages of Memory Pillows

　　Advantages:

　　a. More comfortable: Memory pillows have good adaptability to the human body, so they can disperse the pressure between the head and neck, making sleep more comfortable.

　　b. Better support: The memory pillow material has high elasticity, which means it can provide excellent support performance and maintain its shape during long-term use.

　　c. Reduce respiratory and allergy problems: Memory pillows usually have antibacterial and anti-allergic properties, which can reduce respiratory problems caused by sleep.

　　In the rapidly evolving world of technology, user interfaces (UI) play a critical role in how we interact with devices and systems. As we move towards more streamlined, efficient, and user-friendly interfaces, membrane switches are emerging as a key player in the future of UI technology. Here¨s why membrane switches are becoming the preferred choice for a wide range of applications and why they are poised to revolutionize user interface technology.more importantly, touch panel Made a fighter in the product, not afraid of any competitor’s attack. https://singway-touch.com/

　　membrane switches

　　1. Sleek and Modern Design

　　One of the most significant advantages of membrane switches is their sleek and modern design. Unlike traditional mechanical switches, membrane switches are composed of several layers, including a flexible, thin membrane on the surface. This design not only provides a contemporary look but also allows for the creation of flat, smooth surfaces without protruding buttons. This aesthetic appeal is highly valued in consumer electronics, medical devices, and industrial control panels.

　　2. Enhanced Durability and Reliability

　　Membrane switches are known for their durability and reliability. The construction typically involves polyester or polycarbonate materials, which are resistant to moisture, dust, and other environmental factors. This makes them ideal for use in harsh environments where traditional mechanical switches might fail. Moreover, membrane switches have a longer lifespan due to fewer moving parts, reducing the likelihood of mechanical failure and ensuring consistent performance over time.

　　3. Customizability and Versatility

　　The design flexibility of membrane switches is another reason for their growing popularity. They can be customized to meet specific requirements, including various shapes, sizes, and configurations. This versatility allows designers to create interfaces tailored to unique applications, from medical equipment to consumer electronics and industrial machinery. Additionally, membrane switches can incorporate various features such as tactile feedback, backlighting, and printed graphics, enhancing user experience and functionality.

　　4. Ease of Cleaning and Maintenance

　　In industries where hygiene is paramount, such as healthcare and food processing, the ease of cleaning membrane switches is a major advantage. The smooth, sealed surface prevents dirt, liquids, and contaminants from penetrating the interface, making it easy to clean and disinfect. This feature not only ensures a sanitary environment but also extends the lifespan of the interface by preventing damage from spills and debris.

　　5. Cost-Effective Production

　　The manufacturing process for membrane switches is relatively straightforward and cost-effective. They are produced using printing techniques that allow for high-volume production at a lower cost compared to mechanical switches. This affordability makes membrane switches an attractive option for both small-scale and large-scale applications, enabling companies to implement advanced UI technology without breaking the bank.

　　6. Improved User Experience

　　Membrane switches can significantly enhance user experience through their design and functionality. The ability to incorporate tactile feedback provides users with a satisfying and intuitive interaction, similar to that of traditional buttons. Additionally, the inclusion of backlighting and customizable graphics improves visibility and usability, especially in low-light conditions. These features contribute to a more engaging and efficient user interface.

　　7. Integration with Modern Technologies

　　Membrane switches are highly adaptable and can be easily integrated with modern technologies. They can incorporate touch-sensitive elements, capacitive sensors, and even flexible printed circuits, allowing for advanced functionality and interaction. This adaptability ensures that membrane switches can keep pace with technological advancements, making them a future-proof solution for user interface design.

　　8. Environmental Sustainability

　　As sustainability becomes increasingly important, membrane switches offer an environmentally friendly alternative to traditional interfaces. The materials used in membrane switches are often recyclable, and the production process generates less waste compared to mechanical switches. This eco-friendly aspect makes membrane switches an attractive choice for companies committed to reducing their environmental footprint.

　　9. Application in Emerging Markets

　　The versatility and adaptability of membrane switches make them ideal for use in emerging markets. From wearable technology to smart home devices, membrane switches are finding their way into a variety of new and innovative applications. Their ability to provide reliable, user-friendly interfaces in compact and portable formats positions them as a key technology in the expanding landscape of connected devices and the Internet of Things (IoT).

　　Conclusion

　　Membrane switches represent a significant advancement in user interface technology, offering a range of benefits that make them ideal for current and future applications. Their sleek design, durability, customizability, ease of maintenance, cost-effectiveness, and enhanced user experience are just a few reasons why they are becoming the preferred choice for developers and manufacturers. As technology continues to evolve, membrane switches will play a crucial role in shaping the future of user interfaces, providing innovative and reliable solutions for a wide array of industries. Embrace the future of UI technology with membrane switches and experience the difference in performance and design.

　　When selecting a car camera supplier, it¨s essential to consider their expertise in OEM manufacturing and the range of features they offer. Look for suppliers that provide detailed product specifications, robust quality control, and comprehensive customer support.more importantly, 360 panoramic camera factory Made a fighter in the product, not afraid of any competitor’s attack. https://szdfpls.com

　　Leading manufacturers like those featured on platforms such as szdfpls.com offer high-quality car cameras designed to meet rigorous standards. By choosing a reputable supplier, you ensure that you receive a product that not only enhances your vehicle¨s safety but also stands the test of time.

　　Conclusion

　　OEM car cameras, including waterproof models and car handle cameras, are essential for modern vehicles, offering superior image quality, versatile functionality, and robust durability. By investing in high-quality cameras from reliable suppliers, you can enhance your driving experience with advanced safety features and superior performance. Whether for daily use or specialty applications, these cameras provide the clarity and reliability needed for effective vehicle monitoring.

　　Cold heading and cold extrusion are basically deformation processes under the same conditions, but they are different in operation. Cold heading is a forging deformation of smaller workpieces and is often used in the fastener industry. Cold extrusion is an extrusion deformation of larger workpieces and has a wide range of uses.For the immediate pressure, Non standard hardware factory With its own coping style, it can break the predicament and usher in a new life through the quality of the product itself. https://jieruifasteners.com/

　　1. What is cold extrusion

　　Cold extrusion is a processing method in which a metal blank is placed in a cold extrusion die cavity and, at room temperature, a punch fixed on the press is used to apply pressure to the blank to cause the metal blank to undergo plastic deformation to produce parts. Obviously, cold extrusion processing relies on the die to control the flow of metal and relies on the large-scale transfer of metal volume to form parts. In terms of extrusion equipment, my country has the ability to design and manufacture extrusion presses of various tonnages. In addition to using general mechanical presses, hydraulic presses, and cold extrusion presses, friction presses and high-speed and high-energy equipment have also been successfully used for cold extrusion production.

　　At present, cold extrusion technology has been widely used in industrial sectors such as fasteners, machinery, instruments, electrical appliances, light industry, aerospace, shipbuilding, and military industry, and has become one of the indispensable and important processing methods in metal plastic volume forming technology. With the advancement of science and technology and the continuous improvement of product technical requirements in the automobile, motorcycle, household appliances and other industries, cold extrusion production technology has gradually become the development direction of refined production of small and medium-sized forgings.

　　2. What is cold heading

　　Cold heading is one of the new processes of metal pressure processing with little or no cutting. It is a processing method that uses the plastic deformation of metal under the action of external force, and with the help of a mold, the metal volume is redistributed and transferred to form the required parts or blanks. The cold heading process is most suitable for the production of non standard fasteners such as bolts, screws, nuts, rivets, and pins. The commonly used equipment for cold heading is a dedicated cold heading machine. If the production volume is not too large, it can also be replaced by a crank press or a friction press.

　　Cold heading technology has high productivity, good product quality, and greatly reduces material consumption, reduces production costs, and improves working conditions. Therefore, it is more and more widely used in mechanical manufacturing, especially in the production of standard fasteners. Among them, the most representative products produced by multi-station cold heading machines are bolts, screws and nuts.

　　3. Are cold heading and cold extrusion the same thing?

　　Cold heading and cold extrusion are basically deformation processes under the same conditions, but they are different in operation. Cold heading is a forging deformation of smaller workpieces and is often used in the fastener industry. Cold extrusion, on the other hand, is an extrusion deformation of larger workpieces and is widely used; cold heading is equivalent to a branch of cold extrusion. Simply put, in the process of making bolts, hexagonal head forming is cold heading, and rod diameter reduction is cold extrusion (positive extrusion). Non-cut hexagonal flange bolts (multi-station forming) have both cold heading and cold extrusion. The front shaping of hexagonal nuts is only cold heading, and the hole extrusion in the back process is cold extrusion (positive and negative extrusion).

£ºHowever, with the development of the industry, security screening machine It will also bring us more and more consumer experiences, so that users can really feel the upgrade and change. https://secuzoan.com/

　　CNC machining, also known as computer numerical control machining, is a manufacturing process that utilizes computer digital control technology to operate machine tools for part machining.In order to achieve the goal, custom screw Turn cocoon into butterfly, constantly polish product quality, improve business ability, and finally have a place in the market. https://shwhardware.com

　　It has high precision and repeatability, and can process complex geometric shapes and high-precision parts. By using a pre written CNC program, the motion trajectory, cutting speed, feed rate, and other parameters of the tool on the workpiece are controlled to achieve precise cutting processing.

　　CNC machining can be applied to various materials, including metals (such as aluminum alloys, stainless steel, titanium alloys, etc.), plastics, composite materials, etc. It plays an important role in many industries such as aerospace, automotive manufacturing, medical devices, and electronic equipment.

　　Its advantages include improving production efficiency, reducing manual operation errors, shortening production cycles, and achieving complex shape processing.

　　When it comes to touch panel technology, Singway stands out as a premier choice for both commercial and consumer applications. Renowned for their innovation and reliability, Singway touch panels offer exceptional performance and user experience. However, like any advanced technology, they may encounter occasional issues. This guide explores why Singway touch panels are the best choice and provides solutions for common problems to ensure you get the most out of your investment.In combination with these conditions, silicone rubber keyboard It can still let us see good development and bring fresh vitality to the whole market. https://singway-touch.com/

　　singway touch panels

　　Key Features of Singway Touch Panels

　　1. High-Resolution Display

　　Singway touch panels are equipped with high-resolution displays that deliver crisp, clear visuals. Whether for interactive kiosks, point-of-sale systems, or personal devices, the superior display quality enhances readability and user engagement.

　　2. Advanced Touch Sensitivity

　　One of Singway¨s standout features is its advanced touch sensitivity. With support for multi-touch inputs, these panels offer precise and responsive interactions. This is ideal for applications requiring complex gestures, such as zooming, scrolling, and multi-finger operations.

　　3. Durability and Reliability

　　Built with high-quality materials, Singway touch panels are designed to withstand heavy use and environmental stress. Their durability is complemented by scratch-resistant surfaces, ensuring long-lasting performance even in demanding conditions.

　　4. Versatile Connectivity

　　Singway touch panels support a range of connectivity options, including USB, HDMI, and serial ports. This versatility allows for easy integration with various devices and systems, making them suitable for diverse applications.

　　5. Customizable Solutions

　　Singway offers customizable touch panel solutions to meet specific needs. Whether you require different sizes, aspect ratios, or specialized features, Singway can tailor their products to fit your requirements.

　　6. Intuitive User Interface

　　The user interface of Singway touch panels is designed for ease of use. With intuitive controls and responsive feedback, users can interact seamlessly with applications and systems, enhancing overall efficiency and satisfaction.

　　What do several common ADAS functions do?from vehicle camera supplier Looking at the development prospects, the future will always bring positive effects. https://szdfpls.com

　　1 LKA (lane keeping assist)

　　LKA can help drivers keep their vehicles in lanes and reduce the risk of lane departure accidents caused by driver negligence or fatigue.

　　The LKA system achieves its functions by using cameras, sensors and control systems. The camera is usually installed at the front of the vehicle to capture the lane line in front of the vehicle. The sensor is responsible for monitoring the driving status and direction of the vehicle, including steering angle, vehicle speed, etc.

　　When the vehicle approaches the lane line during driving, the LKA system detects the position and shape of the lane line and makes a judgment based on the driving status and direction of the vehicle. If the system believes that the vehicle is about to deviate from the lane, it will help the driver guide the vehicle back to the normal lane by controlling the steering system.

　　2 ACC (adaptive cruise control)

　　The ACC system uses on-board sensors, including radar, laser radar, etc., to detect the vehicles and obstacles in front of the vehicle during driving, as well as the position and speed of the vehicle. The system can monitor the distance and speed of the vehicles and obstacles in front in real time, and automatically adjust the speed and driving trajectory according to the speed and driving status of the vehicle to maintain a safe distance from the vehicle in front.

　　Compared with traditional cruise control systems, adaptive cruise systems are more intelligent and flexible. Traditional cruise control systems can only drive at a preset speed and trajectory, while adaptive cruise systems can automatically adjust the speed and trajectory according to the actual situation of the vehicle and obstacles in front to maintain a safe distance.

　　In addition, the adaptive cruise system can also automatically adjust the vehicle¨s speed and trajectory according to the speed and driving status of the vehicle and obstacles in front to maintain the relative position with the vehicle in front. This automatic adjustment function can help drivers drive the vehicle more easily while improving driving comfort and safety.

　　3 FCW (forward collision warning)

　　The FCW system uses on-board sensors, including radar, cameras, etc., to detect the distance and relative speed between the obstacle in front of the vehicle and the vehicle. The system monitors the situation in front of the vehicle in real time. When a collision risk is detected, it will issue a warning to remind the driver to take timely measures.

　　The warning methods of the FCW system usually include sound warnings, vibration seats or steering wheels, etc. The level and method of the warning will vary depending on the size and specific circumstances of the collision risk. If the driver does not take timely measures, the FCW system may also automatically intervene in the vehicle¨s braking system to avoid or mitigate the collision.

　　Collision prevention systems are usually combined with other driver assistance technologies such as lane departure warning systems and adaptive cruise control systems to provide drivers with more comprehensive and reliable driving safety protection.

　　4 AEB (advanced/automatic emergency braking)

　　The implementation of the AEB system function requires the cooperation of multiple sensors and controllers. The sensor in front of the vehicle (such as radar, camera or laser) detects obstacles in front. If there is a risk of collision based on speed and distance analysis, the system will warn the driver through warning lights, alarm sounds, etc. If the driver does not brake after the warning, or the system determines that the driver cannot brake in time after sensing the signal, the AEB system will actively intervene and brake when the threshold is exceeded.

　　5 IPA (intelligent parking assist)

　　IPA integrates sensors, cameras and computer algorithms to realize functions such as automatic parking space identification and automatic parking.

　　In actual use, the driver only needs to press the start button of IPA intelligent parking assist, and the system will automatically detect the surrounding environment and find a suitable parking space. Once a suitable parking space is found, the system automatically calculates the best parking trajectory and controls the vehicle to complete automatic parking. The whole process does not require manual operation by the driver.

　　6 BSD (blind spot detection)

　　BSD mainly detects the blind spot range of the rearview mirror through two millimeter-wave radars equipped on the rear of the vehicle. When other road users are detected in the blind spot, the driver is warned to assist driving or changing lanes.

　　7 DFM (driver fatigue monitoring)

　　DFM aims to monitor the driver¨s physiological state and driving behavior, reminding the driver to rest in time when fatigued, so as to ensure driving safety.

　　The DFM system monitors the driver¨s physiological state in real time through various sensors, such as eye closure, head position, heart rate, etc. These data can provide clues about whether the driver is fatigued. For example, when the driver¨s eyes are closed more or the head position is not correct, this may indicate that the driver is in a state of fatigue. In addition, the DFM system also monitors the driver¨s behavior patterns, such as driving speed, braking frequency, etc. These behavior patterns can also reflect the driver¨s fatigue level. For example, when the driver slows down or brakes more frequently, this may indicate that the driver is tired.

　　The DFM system uses specific algorithms and models to comprehensively analyze the driver¨s physiological and behavioral characteristics to assess the driver¨s fatigue level. These algorithms and models are usually based on machine learning and artificial intelligence technologies, and can determine whether the driver is in a state of fatigue based on the driver¨s characteristic data.

　　8 NV (night vision)

　　NV can detect obstacles and pedestrians at a farther distance than ordinary visible light, which is particularly useful in night and low-light environments. By identifying these obstacles and pedestrians, the NV night vision function can provide drivers with additional warnings, allowing them to react in advance and avoid potential dangers.

　　NV night vision can also be combined with other ADAS technologies, such as automatic emergency braking and adaptive cruise control. When the NV night vision system detects potential dangers, it can trigger these higher-level safety systems to automatically take evasive or braking measures, thereby further enhancing driving safety.

　　However, NV performance is affected by many factors such as light conditions, ambient temperature, and equipment quality. Therefore, when using NVD, it is necessary to make appropriate adjustments and use it according to actual conditions.

　　As the economy develops more and more, people’s living standards improve and their requirements for security are getting higher and higher. At the same time, due to factors such as wars in the third world, terrorists and extremists, domestic airports, railway stations and mass gathering places are equipped with more and more high-end security equipment.Sufficient data show that walk through metal detector It can drive many people to find jobs, thus driving economic development. https://secuzoan.com/

　　The performance of security inspection equipment has improved a lot compared with previous years. Security inspection X-ray machines are essential equipment for security inspection channels. How this equipment can distinguish dangerous items such as explosives, drugs, guns, knives, etc., we need to start with the principle of security inspection machines.

　　x-ray machines

　　ZA5030A

　　The security inspection machine is an electronic device that uses a conveyor belt to send the checked luggage into the X-ray inspection channel to complete the inspection. When the luggage enters the X-ray inspection channel, it will block the package detection sensor, and the detection signal will be sent to the system control part, generating an X-ray trigger signal, triggering the X-ray source to emit an X-ray beam.

　　The X-ray beam passes through the inspected objects on the conveyor belt, and the X-rays are absorbed by the inspected objects and finally bombard the semiconductor detector installed in the channel. The detector converts the X-rays into signals, and these very weak signals are amplified and sent to the signal processing chassis for further processing. After these signals are processed, they are displayed on the display screen.

　　”No matter how many layers a package has, X-rays can penetrate it and display the items in the package layer by layer.” Dangerous items are identified by different colors. Multi-energy colored organic matter is displayed in orange, inorganic matter is displayed in blue, and mixtures are displayed in green. High energy/low energy are switched to display. High energy displays metals, etc., and low energy displays non-metals. In the image display system, the X-ray sensor L-shaped photodiode array detector (multiple energies are optional), 12-bit depth, high penetration display increases the brightness of dark areas in the image, so that items hidden behind highly absorbent objects are clearly displayed. Low penetration display increases the contrast of low absorption (easy to penetrate) objects, making easy to penetrate objects clearer; therefore, the X-ray security inspection machine is not a decoration, but actually undertakes the work of protecting railway safety.

　　So how does the security inspection machine detect these dangerous items?

　　1. Image monitoring method

　　Image monitoring method directly determines the object from the X-ray image configuration. Therefore, whether the object is suspicious depends on the image on the monitor or display. Unusual objects or objects with different shapes that appear on the display or monitor should be considered suspicious objects. Objects that cannot be accurately identified should also be considered suspicious objects and need to be carefully investigated. The image can be located and analyzed as needed.

　　2. Color analysis method

　　The color analysis method is to identify the type of material based on the different colors that different materials show under the x-ray image. The various colors that appear on the monitor are a reflection of the density, quality and quantity of the object. Therefore, the quality of the object can be evaluated based on the depth of the image color.

　　Light yellow is generally the color of a single piece of clothing, thin plastic, and a small amount of paper.

　　Orange is generally the color of soap, soap, explosives, drugs, wood, leather products, etc.

　　Dark orange is generally the color of a large number of books, paper, RMB, high-concentration liquids, large bags of rice and flour, etc.

　　Blue is the color of inorganic substances such as copper, iron, and zinc. Thick cables, stun guns, bullets, gun barrels, guns, and knives show different shades of blue. Green is the color of mixtures, stainless steel products, cables, etc. show different shades of green. Red is the color of impenetrable objects, mostly heavy metals and thick objects.