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 Conformal coating, refers to the addition of a layer of protective coating to protect products and improve product reliability, three-proof paint plays a role in isolating electronic components and circuit boards from harsh environments. Conformal coating with excellent performance can greatly improve the service life of electronic products. Narrowly defined three-proof usually refers to anti-moisture and heat, anti-corrosion (including salt spray, acid and alkali corrosive liquids, corrosive gases, preventing electrochemical migration), anti-mold, in fact, three-proof also includes a variety of environmental stress protection, such as anti-vibration, anti-dust, anti-radiation, anti-static, anti-rodent, etc., in order to ensure that the PCBA will not be improperly protected and failures to prolong the service life of the product. As the function of electronic products continue to integrate and intelligent direction, the size of electronic components and electronic a...

  Lead-free soldering does present some solder joint reliability challenges relative to traditional lead (Pb) containing processes. This stems mainly from the differences between Pb-free brazing materials and traditional brazing materials, as well as the adjustment of process parameters. So what are the specific factors that affect the reliability of lead-free solder joints? The following is the relevant expertise compiled by Fitech:     First, lead-free brazing material characteristics on the reliability of the solder joints higher melting point: lead-free brazing material melting point is generally around 217 ℃, than the traditional SnPb eutectic brazing material (melting point of 183 ℃) about 35 ℃ higher. The increased temperature profile results in a solder that is prone to oxidation and rapid growth of intermetallic compounds.   Poor wettability: Pb-free brazing materials have poorer wettability. May lead to product solder joints tensile strength, shear strength...

 The camera module refers to the optical and optoelectronic devices that can convert optical signals into electrical signals. A mobile phone camera module is composed of a CMOS sensor, lens, and IF interface. The function of these components is to input pictures or videos into the mobile phone when taking pictures. The mobile phone processor comprehensively processes and analyzes the image data collected by the lens. CMOS mobile phone camera modules contain MEMS and circuit chips, which require a certain air tightness, low-temperature soldering ability, and excellent drop resistance. Low-temperature soldering can reduce the warping of CMOS photosensitive elements. The common soldering materials used for camera modules include low-temperature rosin-based lead-free solder paste and low-temperature epoxy-based solder paste products. The ultra-fine epoxy solder paste for CMOS is compatible with dispensing, tinning, and other processes. The special solder paste for CMOS s...

 Tin whiskers are elongated, needle-like single crystals of tin that form spontaneously on the surface of pure tin (Sn) or tin-containing alloys. These whiskers are usually only a few microns in diameter, but can be several millimetres or even more than 10 millimetres long, which can cause serious reliability problems. The following is a comprehensive explanation of the mechanism of tin whisker growth, the factors affecting it, and the measures taken to suppress it: Tin whisker growth mechanism 1. Driving force: The driving force for the growth of tin whiskers mainly comes from the reaction between Sn and Cu at room temperature to produce Cu₆Sn₅ intermetallic compounds. This reaction generates compressive stresses within Sn. 2. Compressive stress release: due to the high room temperature homogenisation temperature of Sn, Sn atoms diffuse faster along the grain boundaries. The compressive stress is released by atomic diffusion and rearrangement, resulting in the migrat...

 Flux and rosin each have their own characteristics and advantages in the soldering process, the choice of which is better to use needs to be based on specific application scenarios to decide. Below are the main features and comparisons of fluxes and rosins: Flux: Function: Flux is a chemical substance mainly used to reduce the surface tension between soldered metals, to facilitate the soldering process and to prevent oxidation reactions. It usually consists of an active agent, a solvent, etc., which reduces the surface tension of metals and promotes fusion during soldering. Advantages: Flux has excellent performance in welding metals, especially suitable for occasions requiring high precision and strong corrosion resistance requirements. It has strong active performance and is widely used in high precision applications such as soldering circuit boards. Disadvantages: Some types of flux (such as flux containing rosin) will leave slag and residue after soldering, which...

Tin whiskers are elongated, needle-like single crystals of tin that form spontaneously on the surface of pure tin (Sn) or tin-containing alloys. These whiskers are usually only a few microns in diameter, but can be several millimetres or even more than 10 millimetres long, which can cause serious reliability problems. The following is a comprehensive explanation of the mechanism of tin whisker growth, the factors affecting it, and the measures taken to suppress it: Tin whisker growth mechanism 1. Driving force: The driving force for the growth of tin whiskers mainly comes from the reaction between Sn and Cu at room temperature to produce Cu₆Sn₅ intermetallic compounds. This reaction generates compressive stresses within Sn. 2. Compressive stress release: due to the high room temperature homogenisation temperature of Sn, Sn atoms diffuse faster along the grain boundaries. The compressive stress is released by atomic diffusion and rearrangement, resulting in the migration o...

 Fluxes and flux pastes both play an important role in the soldering process, but there are some distinct differences in their composition, use, form, and application scenarios. Here are the main differences between them: 1, composition: ① flux is usually a variety of chemical substances composed of liquid-like compositions, the main component is volatile organic solvents and a small amount of rosin, active agents. ② flux paste is composed of a variety of chemical compositions of paste combinations, the main components are made of organic solvents, resins, organic acids, thixotropic agents, surfactants and other chemicals. In addition to removing the oxidised layer on the metal surface, it also provides adhesion, anti-oxidation and other functions. The composition of flux paste varies according to the use, such as conventional flux paste may contain organic solvents, rosin, halogen salts, organic acids, thixotropic agents, etc., while the lead-free flux paste may cont...

 The method of cleaning flux residues and the choice of cleaning agent depends on the type of flux, and different fluxes require different cleaning methods. Flux residue is a common problem in the electronic manufacturing process, the choice of cleaning method depends on the nature of the residue, cleaning requirements and the characteristics of the equipment. The following are several commonly used flux residue cleaning methods: 1. Water rinse: use pure water or deionised water for cleaning. This method is simple and easy to use, but may not be able to completely remove all the residues, especially for oily or sticky flux, only for water-soluble flux. 2. Solvent cleaning: the use of anhydrous alcohol, ethanol, special cleaning agents and other organic solvents for cleaning. This method can dissolve the flux, making it easier to remove. However, organic solvents are flammable and explosive, the use of which requires attention to safety. 3. Ultrasonic cleaning: ...