Vacuum casting in silicone molds is an essential process in the automotive prototyping industry. It enables the fast and accurate production of plastic and elastomer parts that are essential for the development of vehicle prototypes. In this article, this process, its advantages and its importance in the automotive sector will be described in detail.

Vacuum Casting Process in Silicone Molds:

Vacuum casting in silicone molds is a manufacturing process used to reproduce plastic or rubber parts from a master prototype. The process involves the following steps:

  1. Creation of the master prototype*: Initially, a master prototype of the desired part is created using techniques such as 3D printing or CNC machining. This master prototype will serve as a model for series production.
  2. Silicone mold making*: The master prototype is used to create a high quality silicone mold. This mold will be the negative of the final piece.
  3. Preparation of casting material*: The appropriate material, such as polyurethane resins, is selected for casting. These resins are chosen according to the properties required for the final part.
  4. Vacuum casting*: The casting material is poured into the silicone mold, which is placed in a vacuum chamber. The chamber is evacuated to eliminate any air bubbles and ensure uniform distribution of the material in the mold.
  5. Curing and cooling*: The mold undergoes a controlled curing and cooling process to allow the material to take its final shape and reach its desired mechanical properties.
  6. Part removal*: Once the material has solidified, the final part is removed from the silicone mold. This process is repeated as necessary to produce multiple copies of the part.

Advantages of Vacuum Casting in Silicone Molds:

This process has several advantages in the automotive prototyping sector:

  1. Speed: Vacuum casting enables the rapid production of prototypes, accelerating vehicle development.
  2. Accuracy: The manufactured parts are highly accurate and reproducible, which is essential in the design phase.
  3. Wide range of materials: Different materials can be used to simulate the properties of the final parts, which facilitates the evaluation of prototypes.
  4. Cost-effectiveness: Compared to other manufacturing techniques, vacuum casting is a relatively inexpensive process.

Applications in the Automotive Sector:

In the automotive industry, vacuum casting in silicone molds is used for the prototyping of interior and exterior parts, such as control panels, headlights, bumpers, and other components. It allows design engineers to evaluate and refine their designs before investing in expensive tools for mass production.


Vacuum casting in silicone molds is an essential technique in the development of prototypes in the automotive industry. It provides an efficient and accurate way to produce plastic and elastomer parts, speeding up the design process and reducing costs. Purchasing engineers play a key role in selecting the right suppliers and materials to ensure the success of this process in the automotive industry.