Search Results

Magnesium high pressure die casting alloys MRI 153M and MRI 230D offer attractive properties at elevated temperatures up to 150°C and 190°C, respectively. The presence of specific alloying elements results in different physical and metallurgical properties of new alloys as well as their solidification characteristics during the HPDC process, compared to AZ91D alloy. Hence, process parameters, such as melt and die temperature and injection profile, should be optimized. Furthermore, principles for proper die design, such as gate thickness and runners system, should be considered and addressed. This paper presents design and process guidelines, in order to optimize the HPDC process of the above alloys and produce high performance components.

Creep-resistant HPDC alloys MRI153M and MRI230D are designated to replace HPDC aluminum alloys in the production of different automotive and non-automotive components. Due to the specific chemical compositions of the MRI alloys; they contain alkaline elements (Ca, Sr) with high affinity to Cl ions, fluxless technology must be used for recycling The present paper describes an technology which was developed for recycling MRI alloys. This technology combines simultaneous bubbling and stirring during batch processing. This operation is performed in order to improve metal cleanliness and reduce the process duration, thereby increasing its efficiency. The mechanical properties of recycled alloys were tested and compared with those of primary alloys. The influence of clean scrap dilution with primary material was also explored. The results obtained illustrate a moderate influence of scrap addition on mechanical properties.

The need to reduce weight of large and heavy components used by the automotive and aerospace industries such as engine block, cylinder head cover and helicopter gearbox housing has led to the development of new Mg gravity casting alloys that provide adequate properties and cost effective solution. The new Mg gravity casting alloys are designed for high stressed components that operate at a temperature up to 300°C. These new alloys exhibit excellent mechanical properties and creep resistance in T-6 conditions. The present paper aims at introducing three new Mg gravity casting alloys designated MRI 201S, MRI 202S and MRI 203S, which were recently developed by the Magnesium Research Institute of DSM and VW. Apart from the excellent high temperature performance of these alloys, they provide adequate castability and dimension stability along with good weldability and corrosion resistance.

Recently several new magnesium alloys for high temperature applications have been developed with the aim to obtain an optimal combination of die castability, creep resistance, mechanical properties, corrosion performance and affordable cost. Unfortunately, it is very difficult to achieve an adequate combination of properties and in fact, most of the new alloys can only partially meet the required performance and cost. This paper aims at evaluating the current status of the newly developed alloys for powertrain applications. The paper also addresses the complexity of magnesium alloy development and illustrates the effect of alloying elements on properties and cost. In addition, the paper presents an attempt to set the position of each alloy in the integrated space of combined properties and cost

High pressure die casting (HPDC) is the dominant process for the production of magnesium components with complex configuration having typically thin to medium wall thickness. The growing use of die cast Mg alloys in the automotive industry, particularly for the production of drive-train components, has led to the development of creep resistant alloys, MRI153M and MRI230D, which were launched into the market several years ago. The present paper aims at exploring the effect of the HPDC process parameters on the porosity and, as a result, on the properties of the two MRI's developed alloys in comparison with common alloys AZ91D and AM50A that are usually considered as benchmark die casting alloys. The outcome of the research performed includes processing guidelines and recommendations, which allow obtaining high quality sound castings. These recommendations should be implemented in the course of design, optimization and production of high-performance components for various applications.

The growing demand for the use of magnesium alloys in the production of automotive powertrain components led to the development of creep resistant diecasting alloys MRI153M and MRI230D. The present paper addresses the main high-pressure die casting parameters, which significantly affect the performance of components, produced of these new alloys. A systematic study was carried out in order to correlate die-casting parameters to the performance of new alloys. The results obtained clearly indicated that optimization of molten metal and die temperatures, injection profile parameters and lubrication mixtures allowed to improve the die castability and service properties of the new alloys and produce high performance components with intricate geometry. This was manifested by production of several practical demonstrators such as gearboxes, oil pans, oil pumps and crankcases.