The materials required for SMT mount include welding and patch materials such as solder, solder paste, adhesive, and flux, as well as process materials such as flux, cleaning agent, heat conversion medium, etc.
A soldier is a significant structural material in the SMT assembly process. It is used to connect the metal surfaces of the welding objects to form solder joints.
Different types of solder have different uses, and different solders are used according to different process requirements. In SMT mount processing, common solders include tin-lead, tin-silver, and lead-free solder.
Tin-lead solder is used in traditional SMT patch processing, and its main elements are tin and lead. The advantages of this solder are low melting point, good fluidity, and easy operation.
However, because it contains lead, tin-lead solder has been gradually phased out and replaced by safer and more environmentally friendly lead-free solder. Tin-silver solder is a lead-free solder whose main components are tin, silver, and a small amount of copper.
The advantages of this solder are low melting point, good fluidity, high welding strength, and high reliability. Therefore, in SMT patch processing, tin-silver solder has become the mainstream.
Lead-free solder is a more environmentally friendly solder. Its main components are tin, silver, nickel, and niobium. Compared with tin-lead solder, the advantages of lead-free solder are that it does not contain lead, meets environmental protection requirements, and has high welding strength and reliability.
However, the melting point of lead-free solder is higher. It needs a higher temperature and time for soldering, which makes the operation more difficult.
The selection of solder is crucial to the soldering quality and efficiency of SMT patch processing.
When we select solder, we should consider specific process requirements and usage environments to ensure welding quality and reliability.
Flux is one of the factors affecting the quality of SMT patch processing welding, and various welding processes require flux.
The primary function of flux is to remove oxides and oil stains, making the metal surface clean for the next step of welding. In SMT patch processing, common fluxes include rosin, organic solvents, and hydrogen peroxide.
Rosin is a traditional soldering flux. The main components are rosin and fatty acid. The advantages of this soldering flux are that it is easy to use and low in cost, but it is volatile and flammable. When we use it, we need to pay attention to safety.
The organic solvent is a new type of flux. The main components are alcohols, ketones, and ethers. The advantages of this type of flux are that it is volatile and non-flammable, and it can remove oxides and oil stains and improve welding quality.
However, the disadvantage of organic solvents is that they are volatile and need to be discharged promptly.
Hydrogen peroxide is an environmentally friendly flux whose main components are hydrogen peroxide and hydrochloric acid.
The advantage of this flux is that it doesn’t contain heavy metals and meets environmental protection requirements. At the same time, it can remove oxides and oil stains to improve welding quality.
However, the disadvantage of hydrogen peroxide is that it is highly corrosive. We need to pay attention to security when we use it.
In short, choosing the suitable flux is crucial to the soldering quality and efficiency of SMT patch processing.
When selecting flux, it is necessary to consider the specific process requirements and use the environment to ensure welding quality and reliability. At the same time, pay attention to the safe use and discharge of flux to protect the environment and personal safety.
The adhesive is the bonding material in SMT patch processing. It is mainly used to mount electronic components on PCB boards.
The type and properties of the adhesive will also affect the mounting effect, such as viscosity, curing time, hardness, etc. Choosing a suitable adhesive can improve mounting efficiency and quality.
In SMT patch processing, common adhesives include epoxy resin, polyurethane, and acrylic acid.
Epoxy resin is a commonly used adhesive with high viscosity, fast curing speed, high hardness, and high-temperature resistance. However, the disadvantage of epoxy resin is that it is highly toxic. Be careful when we use it.
Polyurethane is an environmentally friendly adhesive with the advantages of being non-toxic, odorless, low viscosity, high hardness, and high-temperature resistance. However, the disadvantage of polyurethane is that it takes a long time to cure, and you need to wait a long time before proceeding to the next step.
Acrylic acid is a new type of adhesive. Its advantages are low viscosity, moderate hardness, easy volatility, and no residue. However, the disadvantage of acrylic acid is that it is easy to volatilize and requires ventilation.
When selecting adhesives, it is necessary to consider the quality and reliability of mounting. At the same time, pay attention to the safe use and discharge of adhesives to protect the environment and personal safety.
In addition to the above materials, SMT patch processing requires flux, cleaning agents, heat conversion media, and other process materials.
Flux clean and activate the metal surface for the next step of welding.
Cleaning agents are used to clean pollutants and waste generated during the SMT patch processing.
Heat transfer media are mainly used to heat and cool equipment and materials used in the SMT patch processing.
In short, SMT patch processing requires many materials and process materials to ensure welding quality and efficiency.
Selecting appropriate materials and process materials can improve the mounting effect and product quality. It provides strong support for producing electronic products.
