Picking the right stuff for plastic molds is super important to make sure they last long, work well, and don't cost too much. Here’s how to choose the best materials:
- Know What You Need: Start by figuring out what your mold needs. Think about the type of plastic you’ll use, how many products you plan to make, the conditions during molding (like temperature and pressure), and how long you want the mold to last.
- Types of Mold Materials: There are different kinds of materials for molds, like tool steels, stainless steels, aluminum, and high-performance alloys. Each has its own pros and cons for different jobs.
- Steel Options: If you go with steel molds, consider things like how hard the steel is, how resistant it is to wear and tear, how well it conducts heat, and if it resists rust. Common types of steel for molds include P20, H13, S136, and 420SS.
- Aluminum Alloys: Aluminum molds are great for making small batches or quick prototypes. They conduct heat well and are easier to shape than steel. But they don't last as long and wear out faster.
- High-Performance Alloys: For big production runs or tough jobs, think about using high-performance alloys like beryllium copper or nickel-based alloys. These are super tough and can handle harsh conditions.
- Cost Factor: Look at how much the materials cost and how long the mold will last. Sometimes spending more on a material that lasts longer can save money in the end.
- Surface Finish: Make sure the material you pick lets you get the finish you want on your final product. Some materials might need extra coatings or treatments.
- Production Volume: For small runs or prototypes, aluminum might be better because it’s cheaper and faster to work with. For large production, go with tougher steel or high-performance alloys.
- Corrosion Resistance: If you’re working with plastics that can cause corrosion or have conditions that might corrode the mold, choose materials that resist corrosion.
- Ease of Machining: Check how easy it is to shape the material, especially if you need complex designs.
- Heat Conduction: For molds that need quick cooling or are used with plastics sensitive to temperature, pick materials that conduct heat well to speed up cooling and reduce cycle times.
- Talk to Suppliers: Work closely with suppliers and manufacturers to get their expert advice on the best material for your specific job.
In short, choosing the right mold material means understanding what you need and picking the best option from what’s available. The right choice will help you make high-quality parts and keep production running smoothly.
In today's rapidly developing high-tech era, various electronic products are constantly emerging. And the manufacturing of these electronic products cannot do without plastic molds. Therefore, selecting suitable plastic mold materials has become a very important issue.
Firstly, we need to understand the basic concept of plastic molds. Plastic molds are tools used to manufacture plastic products, consisting of various metals and plastic materials. During the production process, plastic molds need to withstand high temperature, high pressure, and high-speed working environments, so selecting the right materials is crucial.
When selecting plastic mold materials, we need to consider the following aspects:
Wear resistance: Plastic molds must withstand high-speed and high-pressure environments during the production process, so the wear resistance of materials is very important. Generally speaking, materials such as hard alloys and ceramics have better wear resistance.
Heat resistance: Plastic molds must withstand high temperature environments during production, so the heat resistance of the material is also important. Generally speaking, metal materials such as steel and aluminum have higher heat resistance.
Chemical corrosion resistance: Plastic molds may come into contact with various chemicals during use, so the material's chemical corrosion resistance is also crucial. Generally speaking, materials such as stainless steel and nickel based alloys have good resistance to chemical corrosion.
Processing performance: The manufacturing process of plastic molds requires fine processing, so the processing performance of materials is also important. Generally speaking, metal materials such as steel and aluminum have better processing performance.
Cost factor: On the premise of meeting the above performance requirements, we also need to consider the cost of plastic mold materials. Generally speaking, metal materials such as steel and aluminum have relatively low costs, while materials such as hard alloys and ceramics have relatively high costs.
In short, when choosing plastic mold materials, we need to comprehensively consider factors such as wear resistance, heat resistance, chemical corrosion resistance, processing performance, and cost. Only in this way can we select the most suitable plastic mold materials for our own needs, thereby ensuring the quality and production efficiency of electronic products.
Internal mold: mainly refers to the mold core, slider, ejector pin, and inserts. For plastic molds with no special requirements, 45 steel or 50 steel is generally used; If the requirements are slightly higher, P20 pre hardened plastic mold steel is usually chosen; If there are higher requirements for the internal parts of plastic molds, 718 super pre hardened plastic mold steel must be used; For precision plastic molds with very strict requirements, 738 (national standard 4Cr2NiMnMo) steel should be selected; If customers want to polish plastic molds to be as shiny as mirrors, most mold factories will choose NAK80 mirror plastic mold steel; In the process of producing plastic products using plastic molds, sometimes corrosive gases are generated. In this case, it is necessary to choose corrosion-resistant mold steel for production, such as M300 corrosion-resistant steel.
Mold base: Generally speaking, the most basic mold base is also made of 45 steel; The most commonly used mold base material is 50 steel; If there are specific requirements for the mold base, 55 # mold steel will be selected; The most exquisite plastic mold should choose GS638 (American standard P20, German standard GS638, national standard 42CrMo) mold steel, which can meet the requirements of use.
Guide post: There are three options, the first one is No. 20 (S20C) or 20Mn2B (SMn420), the treatment method is carburizing and quenching, and the hardness after treatment should be greater than 55HRC; The second type is T8A or T10A, and the treatment method is surface quenching, with a hardness of less than 55HRC after treatment; The third type is 45 steel, which is treated by tempering, surface quenching, and low-temperature tempering. The hardness after treatment should be greater than 55HRC.
Guide sleeve: Most mold factories use H62 brass or bronze alloy to make guide sleeves.
Lining: Most mold factories choose 45, 50, and 55 steel for lining, and the treatment method is surface quenching. The hardness after treatment should be greater than 55HRC.
Push rod, ejector pin, and pull rod: materials such as T8, T8A, T10, and T10A are used, and the treatment method is quenching and low-temperature tempering. The hardness after treatment should be greater than 55HRC; The processing method for 45, 50, and 55 steel is quenching, and the hardness after treatment should be greater than 45HRC.
Various types of plates: General plastic mold factories will choose to use 45 #, 50 #, 40Cr (quenched and tempered) and structural steel Q235~Q275. If a large board is needed, ductile iron can be used instead.
Choosing the right material for plastic molds is crucial, as it affects the quality, durability, and lifespan of the molds. When selecting materials, several factors need to be considered: what plastic is used, how the mold is designed, and how many products are expected to be made. Here are some tips for selecting materials:
First, clarify which type of plastic it is: the type of plastic used directly affects the selection of mold materials. Different plastics have different characteristics, such as melting point, shrinkage rate, and viscosity, which can affect mold design and material selection.
Think about mold design again: Mold design is also very important. The mold must be able to withstand the high temperature and pressure during the injection molding process without deformation or warping. The design also needs to make it easy to remove the finished product from the mold.
Next is the estimated production volume: production volume is also a factor to consider when selecting materials. If the production is large, wear-resistant and durable materials must be used; If the output is small, use materials that are not as durable but still sufficient.
Don't forget about the cost issue: material costs also need to be taken into account. Expensive materials may have better performance, but if produced in small batches, it may not be cost-effective.
We also need to find materials with good thermal conductivity: materials with good thermal conductivity can shorten the production cycle, improve production speed, and make the manufacturing process more efficient.
Finally, surface treatment: The surface treatment of the mold will affect the quality of the final product. Choosing the right surface treatment can reduce defects and improve the overall quality of the finished product.
In short, choosing the right material for plastic molds is crucial for ensuring high-quality and efficient production. As long as factors such as plastic type, mold design, production volume, cost, thermal conductivity, and surface treatment are taken into account, manufacturers can select materials that are both durable and of high quality.
