Steel vs. Aluminum for Plastic Injection Molds

ICOMold has always offered hardened steel material for plastic injection molds. So how do you know if a steel mold or an aluminum mold is best for your plastic injection molding project? There are advantages and disadvantages of each, which we will explain here.

 

Advantages of Steel Over Aluminum Molds

1. Ability to Make Complex Parts: A part design can be, in some cases, too complex to be injection molded with an aluminum mold. A steel mold will be required due to the complexity of the part design. This is not unique to ICOMold – this is a universal limitation that all mold makers face.
2. Surface Finish Options: Steel molds offer more options when it comes to part surface finishes. The number of surface finishes possible with an aluminum mold is limited, and custom finishes are not possible as they are with steel molds. The difference in available surface finishes based on mold material affects all mold makers, not just ICOMold.
3. Ease of Design Modifications: Mold modifications due to part design changes are limited on aluminum molds compared to steel. For one thing, a steel mold can be modified by welding. Therefore, if there is a good chance that your part may be undergoing design revisions that will require mold modifications, a steel mold can better accommodate that.
4. Less Flash: Because steel is harder, there is less chance for flash on the part as there is with using a softer aluminum mold.
5. Durability: While aluminum molds will hold up for smaller part runs, steel molds are more durable. Our steel production molds carry a lifetime warranty – if your mold ever requires any repairs, we will cover the cost of repairs, or even replacement, for the entire time we are producing your parts for you.

 

Advantages of Aluminum Over Steel Molds

1. Speed: Aluminum molds can be faster to make than steel molds. Since aluminum is softer than steel, it is easier to machine, so the process can be quicker.
2. Cost: Aluminum molds can cost less than steel molds.

 

Plastic Injection Molding Quote

Is an aluminum mold right for your plastic injection molding project, or a steel mold? This page explains the difference.