AM-lite is a new magnesium alloy, specially formulated to provide excellent die castability with significant cost advantages and a high-quality as-cast surface that is highly suitable for decorative surface finishing operations. It has been developed to replace zinc, aluminium or magnesium (alloy AZ91D) die castings and plastic injection mouldings.

AZoM - Metals, Ceramics, Polymer and Composites - AM-lite – A Die Casting Magnesium Alloy Alternative to Zinc, Aluminium, AZ91D and Inkection Moulded Plastics from Advanced Magnesium Technologies
Advantages of AM-lite over Its Competitors

AM-lite has several advantages over its competitors:

Competing Materials





Advantages of AM-lite ®

Zinc


vs


· Cheaper: three times as many parts per tonne

· Three times lighter

· Higher design strength

· Lower reject rates for surface coated products

Aluminium


vs


· Cheaper: lower metal, diecasting and surface finishing costs

· Superior as-cast surface

· Improved surface finishing characteristics

· Lighter weight: 26% reduction in density

Magnesium alloy AZ91D


vs


· Cheaper: lower diecasting and surface finishing costs

· Improved diecastability

· Higher strength

· Better as-cast surface

· Improved recyclability

· Superior substrate for surface finishing operations

· Easily electroplated

Plastics (e.g. ABS)


vs


· Cheaper: lower material costs

· Higher strength and stiffness

· Electrical conductivity for electromagnetic shielding

· Thermal conductivity

· Metallic feel
Development of Applications for AM-lite

Advanced Magnesium Technologies is working with a number of international companies to develop new applications for AM-lite, such as consumer electronics, hardware and auto parts requiring decorative surface finishes.
Commercial Opportunities for AM-lite ®

It is very expensive to decoratively surface finish existing magnesium alloys. As a result, most of this business goes to zinc and aluminium die castings or plastic mouldings. There is a significant market opportunity for a cost effective magnesium die casting alloy that has better die castability attributes than existing magnesium alloys, plus an improved as-cast surface finish that is suitable for decorative surface finishing operations. Together with its research partner CAST, AMT has developed AM-lite which fulfils these market requirements. AMT has also worked together with MacDermid Industrial Solutions to develop suitable electroplating technology and conversion coating technology for AM-lite.
What is AM-lite ®

AM-lite is a high surface finish die casting alloy suitable for applications that currently utilise zinc, aluminium or magnesium (alloy AZ91D) die castings, or plastic injection mouldings. AM-lite has significant cost advantages and other benefits when compared to these competitor materials.
Advantages of AM-lite ®

The key advantages of AM-lite in decoratively finished products over zinc alloys are its light weight, lower material cost per unit volume and lower reject rates in painting and powder coating. Compared to plastics the key advantages are electrical conductivity for electromagnetic shielding, thermal conductivity and metallic feel. When compared to aluminium die casting alloys the main advantage of AM-lite is a superior as-cast surface combined with improved and lower cost surface finishing characteristics. Compared to the existing general purpose magnesium die casting alloy, AZ91D, AM-lite offers improved die castability, better as-cast surface, improved recyclability and a superior substrate for surface finishing operations at significantly lower costs.
Advantages of AM-lite over AZ91D

The most commonly used magnesium die casting alloy, AZ91D, suffers a significant disadvantage in the cost of surface finishing of articles made from this alloy. High quality as-cast surfaces are difficult to achieve and surface finishing operations generally require additional processing steps leading to higher cost.

AM-lite, in combination with appropriate die design, die casting process parameters, and decorative coating technologies, overcomes this disadvantage. An as-cast surface finish that is superior to AZ91D can be readily obtained. At the same time AM-lite has excellent die casting characteristics with better die filling and surface feature reproduction than AZ91D. It also has a much wider diecasting operating window, leading to reduced cycle times in production and large potential cost savings. AM-lite is very easy to recycle and, in combination with the use of AM-cover and AM-converter technologies, the cost of external recycling can be virtually eliminated.
Electroplating of AM-lite ®

The electroplating process for AM-lite was developed by MacDermid Industrial Solutions, a global supplier of chemicals and technology to the surface finishing industry. Macdermid’s Bondal ® Mg process, that was specially developed for AM-lite, takes advantage of the alloy’s favourable surface chemistry to greatly simplify pre-treatment steps that are necessary before application of electroplated layers of copper, nickel and chromium. The pre-treatment for AM-lite involves one step more than is necessary for electroplating of zinc die castings but thereafter the process is the same as for the electroplating of zinc and surface finishes of equivalent high standard can be obtained.
Patent

The technology for AM-lite is being patented internationally and AMT has the exclusive worldwide rights for commercialisation of the alloy.
Current Status

AM-lite was first introduced to the market in June 2005. Since then there has been a high level of activity towards utilisation of the alloy in commercial products. Die casters have trialled the alloy, product developers have assessed which products are best suited for early introduction of the alloy, prototypes have been developed, surface finishing processes have been adjusted to suit the alloy and extensive testing has been carried out on manufactured articles. The fruits of these efforts - the first products made from AM-lite – are currently coming onto the market.