A study on reheating characteristics for thixo die casting process with electromagnetic stirring and extruded aluminum alloys and their mechanical properties

Rheoforming is becoming the choice of the casting industry which relies on the semi-solid slurry for high integrity structural parts. The potential of rheoforming with LSPSF (Low superheat pouring with a shear field) for aluminum alloys was investigated in the present work. High quality semi-solid slurries of a series of aluminum alloys were manufactured by LSPSF process, such as casting alloy A356, high strength alloy 201, secondary die casting alloy A380 and wrought alloy 2024, 6082 and 7075, in which the primary α-Al presented spherical, small and homogeneous distribution, especially with zero-entrapped liquid. Applications of LSPSF in high pressure die casting process and squeeze casting process were presented. Results showed that LSPSF rheoforming could improve microstructures and increase mechanical properties.

Download Full-text

Development of 2-Cavity Die Casting Process for AM50 Mg Steering Column Lock Housing Module

Materials Science Forum ◽

10.4028/www.scientific.net/msf.510-511.334 ◽

2006 ◽

Vol 510-511 ◽

pp. 334-337

Author(s):

Shae K. Kim

Keyword(s):

Magnesium Alloy ◽

Aluminum Alloys ◽

Magnesium Alloys ◽

Weight Reduction ◽

Die Casting ◽

Casting Process ◽

Research Strategy ◽

Good Choice ◽

Weight Basis ◽

Die Casting Process

It is obvious that automotive industry worldwide is predicting significant growth in the use of magnesium alloys for weight reduction to decrease fuel consumption and emission. About a half decade ago, the price of magnesium alloys was more than twice that of aluminum alloys on a weight basis. Currently, magnesium alloys cost about one and a half times that of aluminum alloys on a weight basis, and thus the price of magnesium alloys is the same as or lower than that of aluminum alloys on a per volume basis. However, in considering the performance of magnesium components (not their specific mechanical properties) and recycling aspect of magnesium alloys, it is required to realize niche applications of magnesium alloys, which meet the cost requirement on performance basis and/or offer more than weight reduction. There are many other factors that make magnesium a good choice: component consolidation, improved safety for driver and passengers, and improved noise vibration and harshness (NVH), to name a few. As one of these efforts to adopt magnesium alloys in automotive component, this paper describes the research strategy of cold chamber type 2-cavity die casting of AM50 magnesium alloy for developing the steering column lock housing module with emphasis on cost driving factors and necessities for cost reduction, explaining why AM50 magnesium alloy is chosen with design and die casting process optimization.

Download Full-text

Study on Local Extrusions' Effects on Improvement of Die Casting Prismatic Parts' Forming Quality

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.312.475 ◽

2013 ◽

Vol 312 ◽

pp. 475-479

Author(s):

Wei Gang Zheng ◽

Cun Hong Yin ◽

Yu Hong Yuan ◽

Zhen Min Pan ◽

Chao Tang

Keyword(s):

Mechanical Properties ◽

Die Casting ◽

Casting Process ◽

Extrusion Process ◽

Shrinkage Porosity ◽

Shrinkage Cavity ◽

Prismatic Parts ◽

Porosity Defects ◽

Die Casting Process ◽

Casting Production

This paper analyzes traditional die casting process to find out the reasons that cause shrinkage cavity and porosity defects in casting. An optimized process of die casting by using local extrusion is proposed. A device used in local extrusion which realizes forcing compensating contraction on key parts of crankcase is designed and the parameters of local extrusion process are discussed. Compared the mechanical properties and microstructure of local extrusion used in die casting production with traditional. It shows that local extrusion used in die casting production can not only achieve the aim eliminating shrinkage porosity and cavity of a casting but also can refine grain to improve the mechanical properties.

Download Full-text

The Effect of Scandium on the Mechanical Properties of A356 Aluminium Alloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.707.144 ◽

2016 ◽

Vol 707 ◽

pp. 144-147

Author(s):

Ying Pio Lim ◽

Wei Hong Yeo ◽

A. Masita

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Aluminium Alloy ◽

Die Casting ◽

A356 Alloy ◽

Charpy Impact ◽

Casting Process ◽

Die Casting Process ◽

Charpy Impact Strength ◽

A356 Aluminium Alloy

In this project, the addition of scandium (Sc) into A356 aluminium alloy was studied for its effect on the mechanical properties after gravity die casting process. Scandium addition was administered at the weight percentages of 0.1, 0.2 and 0.3. The results obtained in this work revealed that scandium can significantly enhance the mechanical properties of A356 alloy in terms of tensile strength, hardness and charpy impact strength. In general, the addition of 0.2 wt% Sc in A356 alloy was found to be able to achieve the maximum tensile strength of 172.94MPa as compared to 136.03MPa for sample without Sc. No significant improvement in tensile strength was found when more than 0.3wt% added to the alloy. As for hardness, the sample with 0.3 wt% Sc attained the maximum Vicker’s hardness of 86.60 HV as compared to 76.48 HV for unmodified A356. Similarly, the addition of 0.3wt% Sc in A356 can achieve highest impact energy of 2.71J as compare to 1.09J for unmodified A356.

Download Full-text