What is the Mim silicone encapsulation injection molding process?

Mim silicone encapsulation injection molding is a special manufacturing process that combines the characteristics of two materials to produce products with specific properties. “MIM” is the abbreviation for Metal Injection Molding, which is a process of mixing powdered metal with adhesive to form granular materials, which are then injected into the mold and solidified through an injection molding machine. Afterwards, degreasing and sintering steps are required to obtain the final dense metal components.

When this technology is used for silicone encapsulation, it means covering a layer of silicone adhesive on metal components that have already been made through MIM technology. Here are some key steps in this process:
Design phase: The design includes the structure of the inner core metal material part and the outer silicone covering part.
Material selection: Select suitable metal powders and adhesives for the MIM process, and determine the type of silicone suitable for the final product.
Preparation feeding: Mix metal powder with suitable adhesive to form granular materials that can be injected.
Injection molding: Using standard injection molding equipment to inject feed into precision designed molds to form the desired shape.
Degreasing treatment: Remove all adhesive components from cured but not fully hardened components.

Sintering treatment: Heating the degreased components at high temperature to achieve full density and obtain the required mechanical properties of the metal material.
Cooling and cleaning: After sintering, the components need to be cooled and may require further processing or polishing to achieve precise dimensional requirements.
Prepare the encapsulation mold: Make or prepare corresponding silicone rubber compression or pouring molds for the silicone encapsulation process.

Silicone rubber injection/pouring/immersion coating and other operations:
If liquid silicone rubber (LSR) is used, it can be directly injected into the space containing rigid structural components.
If solid silicone rubber is used, it may involve molding or other methods to make it adhere to rigid structural components.
Vulcanization shaping: For certain types of silicone rubber, a vulcanization process is required after coating to ensure that its elasticity and other physical properties achieve the expected results.
Surface treatment: Necessary polishing, polishing, or other post-treatment processes are carried out on the surface according to product requirements to improve product quality perception and functional performance
Quality inspection: The final product needs to go through a strict quality inspection process to ensure that all indicators meet the standard requirements

This process is applicable to products that require both hard and wear-resistant properties, as well as good tactile or special insulation properties, such as the casings of some high-end electronic devices and medical equipment.