Rapid Injection Molding
Rapid injection molding uses tooling made of aluminum, soft steels, or semi-hardened steels of various grades. The primary reasons for choosing rapid injection molding are rapid prototyping and bridge tooling.
When seeking swift production of prototypes or volumes, it is critical to prioritize injection-molded resins over 3D-printed resins, machinable plastics, or other materials. While traditional injection molds are considered for mass production of parts, there is also a need for a less-cost “bridge tool” that can be processed quickly to produce parts.
The Types of Rapid Injection Molding
Unlike traditional injection molding, which typically takes several months to finish, rapid injection molding can deliver parts to you within a few weeks, here are the rapid injection molds commonly used.
Aluminum Injection Molds
Aluminum can be processed twice as fast as steel, and no subsequent heat treatment is required – two factors that together significantly reduce tooling time. Aluminum also has good thermal conductivity enables rapid cooling, greatly improving production efficiency.
However, aluminum does not have a high polish finish compared to steel, which can affect the appearance of parts that need to be glossy or optically clear for rapid injection molding. If you need high-precision parts, aluminum molds may not be the best choice.
Soft and Semi-Hardened Steel Molds
P20 is a commonly used mold steel material with good machinability, making it easy to process and cut. For applications requiring high impact and stress resistance, the higher hardness and toughness of 718 (semi-hardened steel) would make it the preferred choice. But if you are considering cost and availability, P20 might have advantages over 718.
Normally, aluminum molds have a lead time of a few weeks and can withstand 5000-10,000 injection cycles. In contrast, soft steel and semi-hardened steel molds typically need one month or longer lead time, but the injection cycles can range from tens of thousands to hundreds of thousands.
Rapid Injection Molding Materials
Suitable for aluminum and P20 soft steel molds:
- Plastic materials: ABS, Polypropylene (PP), Polyethylene (PE), Polycarbonate (PC), Acrylic, etc.
- Low-pressure materials: Soft plastics requiring less force during injection
Suitable for semi-hardened steel mold:
- High-strength plastics: Nylon, Polycarbonate (PC), Acetal (POM), Polyethylene Terephthalate (PET), etc.
- Engineering resins: PEEK, Ultem, LCP (Liquid Crystal Polymer), etc.
Benefits of Rapid Injection Molding
- Shorter Lead Time: Rapid injection molding significantly reduces lead times compared to traditional mold-making methods. This allows for quicker production and faster product development cycles.
- Cost-Effective: By streamlining the mold-making process and reducing the need for extensive tooling, rapid injection molding helps lower overall production costs, especially for small to medium production runs.
- Prototype Verification: Rapid injection molding allows for the creation of functional prototypes that closely mimic the final product, aiding in design validation and testing before full-scale production.
- Time-to-Market: With rapid injection molding, companies can accelerate their time-to-market strategies, responding swiftly to market trends and gaining a competitive edge.
Overall, rapid injection molding offers a combination of speed, cost-efficiency, and flexibility that can significantly benefit companies looking to innovate and bring products to market quickly and efficiently. You can choose the right rapid injection mold by carefully considering the lead time, quantity, budget, and quality requirements to achieve your projects.
