Silver GIT - The new technology in the field of metal injection molding

 

With the Silver GIT method, an inert gas (nitrogen) is injected into the melt where it is used to perform various functions.

 

The gas can compensate shrinkage to avoid undefined hollows.

 

Furthermore, the gas can hollow the metallic product which reduces the weight. The gas also reduces the internal stress of the product and spreads it evenly.

 

Depending on the melt used, you only have to modify the mold to produce already existing articles with the Silver GIT method. You can use the method for rod-shaped products, such as simple handles for the furniture and car industries. It is also suitable for complex structures where for example mass concentration is to be prevented for reasons of aerodynamics. Here, shrinkage compensation is combined with defined voids. Last but not least, even medium-conducting pipes can be produced in a way that was not possible until now.

 

The Silver GIT method has the following advantages:

 

- It reduces weight by purposefully creating hollows
- It changes hollows into defined hollows
- It creates stress-reduced products
- Under certain conditions, it reduces cycle times
- It increases freedom of design

 

First, you have to equip the mold with a gas injection system that allows injecting the gas directly into the melt.

 

With high surface qualities, the melt's rate of crystallization can be reduced. This will result in high surface qualities for the hollow, too.
The machine used for production needs to be upgraded with a Silver GIT gas controller.

 

In 1997, engineer Ulrich Stieler together with the company Strothmann (Gütersloh) conducted the world's first successful studies in using a standard mold on a handle for the furniture industry.

 

Stieler Kunststoff Service GmbH, with its know-how in gas injection technology and its experiences from testing the technology, started cooperating with Prof. Dr. Ing. Kallien from Fachhochschule Aalen (University of Applied Sciences, Aalen). He contributed his know-how in metal injection. Together, they were able to prove the efficiency of Silver GIT by producing a prototype of a car door handle.

 

A car door handle, produced by means of gas injection and zinc die-casting

 

Only to a limited extent can it be compared to the already known gas injection technology in plastics engineering - a comparison that is based on completely different dimensions of temperature, pressure, and speed. What plays an important role now is the injector technology, the mold temperature control, and the guiding of the melt.

The plant engineering, too, was specifically modified, to meet the high demands.