Application of ASM wire bonding machine in metal powder production

1. The softening point of powder coatings

The softening point of powder coatings is the main basis for setting the bonding temperature of the automatic wire bonding machine. The higher the softening point, the higher the bonding temperature should be. The higher the bonding temperature, the better the bonding effect, but too high will cause agglomeration. Generally, the actual bonding temperature is generally about one-half of the softening point. In order to accurately set the bonding temperature, first, a formula should be tested for softening point before trial mixing; then set the bonding temperature for trial mixing based on this, and after several tests, find the best bonding temperature as the batch The operating parameters of the second. The softening point of each batch of materials will be different. Therefore, each batch of materials should be tested, mixed, and determined before the formal mixing to ensure that there is nothing wrong.

2. Water temperature and flow rate of cooling water

Lowering the cooling water temperature and increasing the water flow rate can increase the heat absorption efficiency and increase the cooling force. It is beneficial to maintain constant temperature bonding under high-speed dispersion conditions. When normal temperature and normal pressure cooling water cannot achieve the expected results, low-temperature water and measures to increase the pressure or flux of water should be considered.

3. Rotation speed of bonding paddle

As the speed of the stirring paddle increases, the frictional heat between the paddle and the material increases, which will increase the temperature of the material. At the same time, the strength of the material being dispersed will also increase. The former increases the propensity to agglomerate the paddle surface; the latter is beneficial to the bonding effect. Therefore, it is necessary to find a moderately balanced main rotor speed for a certain formula. Under the premise of ensuring the bonding effect, reduce the speed as much as possible to ensure the stable and even temperature rise of the material and reduce the tendency of impurities.

4. Constant temperature bonding time

Under normal circumstances, proper extension of the constant temperature bonding time can improve the bonding effect. The tendency of materials to agglomerate increases when the time is too long.

5. Temperature control accuracy

The temperature control accuracy refers specifically to the difference between the actual temperature of the material and the temperature measured by the temperature controller at the beginning of the bonding of the bonding cylinder and the change in the temperature of the material from the beginning to the end of the bonding. The smaller the above difference and the smaller the change, the higher the temperature control accuracy. The higher the temperature control accuracy, the more beneficial it is to the bonding effect; the more beneficial it is to reducing bonding defects and failures. Usually the measurement error of the temperature controller itself can be ignored, but the measurement point error of the probe cannot be ignored. This error is greatly affected by the depth of the probe into the material and the thickness of the adherent on the probe surface. In the design, try to make the probe deep into the material; in use, the attachments on the surface of the probe should be cleaned frequently.

6. The proportion of the formula

When some formula materials with a small specific gravity are mixed, the powder coating will float up, which is very easy to produce the disadvantages of uneven mixing. The solution is to use special blades.

7 Types of metallic pigments

Commonly used metal pigments are copper powder (gold powder), aluminum powder (silver powder), and pearl powder. According to the particle structure and size of the pigment, there are coarse powder and fine powder. Among them, coarse silver powder is also called flash silver; fine silver powder is also called floating silver. For metal powder with fine silver powder, when bonding and mixing, the silver powder must be broken and dispersed to achieve a high-gloss silver powder effect. Its operation process has the following characteristics: it is added at the same time with the bottom material; the paddle speed is higher; the paddle speed and cold water jointly adjust the bonding temperature. For metal powder with coarse silver powder, when bonding and mixing, the silver powder should not be crushed or dispersed too much to ensure its glittering effect. Its operation process has the following characteristics: add pigment when the temperature of the bottom material rises to the bonding temperature; lower agitating paddle speed; the adjustment of the bonding temperature is mainly based on the paddle speed and cooling water as the secondary. The stability of the bonding effect of gold powder is poor. There will be color difference when spraying the same formula of metal powder with spray guns produced by different manufacturers. This is due to the difference in the electricity application of different spray guns to the material. In order to solve the above shortcomings, the bonding and mixing of gold powder should take measures such as high dispersion, high bonding temperature, and long time. In addition, using pearl powder (non-metal inorganic salt) pigment instead of gold powder can obtain a more stable bonding effect. In comparison, different pigments are different in terms of the ability to easily obtain the bonding effect. Their performance is as follows: ultra-fine floating silver> ultra-fine gold powder> pearl powder> general gold powder> flashing silver powder.

8. Heating method

The water-heated bonding mixer is more suitable for the production of metal powders that use coarse pigments such as flash silver and pearl powder. Friction heating bonding mixer is more suitable for the production of metal powders using fine silver, floating silver and other fine pigments.

9. Development prospect of automatic wire bonding machine

With the expansion of the use of metal powder and the improvement of quality requirements, the market demand for metal powder will increase. This will definitely promote the operation convenience, performance and quality of the automatic wire bonding machine. The specific performance is: a higher-level automatic control system; the whole process from feeding to packaging is completed automatically. The inner wall in contact with the material has a higher self-cleaning ability, which is easier to operate and more convenient to change the color and clean the machine. ASM automatic wire bonding machine/ASM bonding machine has a more stable bonding effect and less solidified blocks.