Injection molding is one of the most widely used manufacturing processes today because of its versatility. It has significantly evolved over the past century, allowing for the production of high-quality and complex parts across industries. The basis of this process, as explained by a reputable plastic injection molding company, is melting plastic raw materials and using high pressure to inject them into a mold to cool and solidify into a final part.
While the process seems simple, material selection is a complex and important part of it. The chosen materials directly impact the appearance, durability, strength, and all other aspects of the final product. In today’s article, we share detailed information to help you make an informed and strategic choice for your project.
What material should I use for injection molding?
Selecting the right material requires a comprehensive understanding of the properties of different plastics. With this guide and the help of a reliable manufacturer, you’ll be able to pick the best plastics for your application:
Your requirements
It’s important to consider what properties your final product should have. These include flexibility, strength, chemical resistance, temperature resistance, durability, and more. For example, if your goal is to produce impact-resistant, lightweight parts for consumer electronics like smartphone accessories, consider high-strength materials that have excellent impact resistance.
Your manufacturers will help you select the materials that meet all requirements of your application and ensure optimal performance and functionality.
Consider production rate and volume
Evaluate the speed and scale of the production process. High-volume production usually requires plastics with increased durability and faster cycle times. For instance, when it comes to mass production of consumer goods, materials with fast cooling properties, such as some thermoplastics can help speed up production cycles.
Thermosets vs. thermoplastics
Thermoplastics are materials that, once they’re molded, can be heated again and reshaped without any alterations to their chemical structure. This characteristic makes them recyclable and highly versatile. Some common examples of thermoplastics include polystyrene (PS), polypropylene (PP), and polyethylene (PE). This ability to withstand manifold cycles of processing without degradation is valuable in many applications.
On the other hand, thermostats are plastics that cannot be reformed or remelted once they’re set. This is because they undergo chemical changes that create a three-dimensional, rigid network which renders them structurally stable and heat resistant. Some typical examples are phenolic plastics and epoxy resins.
Environmental and regulatory compliance
Choosing biodegradable or recyclable materials can help reduce the environmental impact of your product. Also, you should make sure that the materials you choose comply with the any industry-specific regulations, such as FDA approval for food-grade applications or RoHS compliance for electronics.
The overall cost of production
Another essential factor to consider is the cost, as budget constraints often play a significant role in material selection. While high-performance materials such as polyphenylene sulfide (PPS) or polyether ether ketone (PEEK) offer superior properties, they are also more expensive, so balancing performance with cost-effectiveness is important, especially when it comes to high-volume production.
For applications that are less demanding, materials like PS or PP can deliver great results without exceeding budget limits.
Testing and prototyping
Before you make your final choice, it’s best to conduct thorough testing and prototyping. This will allow you to analyze the performance of the materials under real-world conditions. It will also help you identify any potential issues early in the process, saving you both time and resources in the long run.
Rely on experts
Consulting with an experienced manufacturer can give you valuable insights into which material is best for your application. Reputable companies with comprehensive experience can skillfully guide you through the entire process, including material selection, and make sure that your project meets your cost, performance, and environmental goals.