The objective of this study is to review and evaluate the applications of magnesium in the automotive industry that can significantly contribute to greater fuel economy and environmental conservation. In the study, the current advantages, limitations, technological barriers and future prospects of Mg alloys in the automotive industry are given. The usage of magnesium in automotive applications is also assessed for the impact on environmental conservation. Recent developments in coating and alloying of Mg improved the creep and corrosion resistance properties of magnesium alloys for elevated temperature and corrosive environments. The results of the study conclude that reasonable prices and improved properties of Mg and its alloys will lead to massive use of magnesium. Compared to using alternative materials, using Mg alloys results in a 22% to 70% weight reduction. Lastly, the use of magnesium in automotive components is increasing as knowledge of forming processes of Mg alloys increases.

Magnesium and its alloys applications in automotive industry

Current research progress in grain refinement of cast magnesium alloys: A review article

A Review on Casting Magnesium Alloys: Modification of Commercial Alloys and Development of New Alloys

Microstructure, mechanical properties and bio-corrosion properties of as-cast Mg–Zn–Mn–Ca alloys were investigated for biomedical application in detail by optical microscopy, scanning electronic microscopy (SEM), mechanical properties testing and electrochemical measurement. SEM and optical microscopy observation indicated that the grain size of the as-cast alloys significantly decreased with the increasing of Ca content up to 0.5 wt.%. Further increasing of Ca content did not refine the grain more. The phase constitute was mainly controlled by the atomic ratio of Zn to Ca. When the ratio was more than 1.0–1.2, the alloy was mainly composed of primary Mg and lamellar eutectic (α-Mg + Ca 2 Mg 6 Zn 3 ), while the alloy was composed of primary Mg and divorced eutectic (α-Mg + Mg 2 Ca + Ca 2 Mg 6 Zn 3 ) when the atomic ratio was less than 1.0–1.2. The yield strength of the as-cast alloy increased but the elongation and the tensile strength increased first and then decreased with the increasing of Ca content. It was thought that Mg 2 Ca phase deteriorated the tensile strength and ductility. Electrochemical measurements indicated that Mg 2 Ca phase improved the corrosion resistance of the as-cast alloy.

Microstructure, mechanical properties and bio-corrosion properties of Mg–Zn–Mn–Ca alloy for biomedical application

Microstructure, mechanical properties and bio-corrosion properties of Mg-Si(-Ca, Zn) alloy for biomedical application.

Effects and mechanism of Ca on refinement of AZ91D alloy

Effect of Ca/Sr composite addition into AZ91D alloy on hot-crack mechanism

Weight reduction to improve automobile fuel economy has triggered renewed interest in magnesium. The effects of Ca/Sr separate and composite additions to AZ91D magnesium alloy on its microstructure and mechanical properties have been investigated. The results indicate Ca can refine both the grain and eutectic phase of AZ91D magnesium alloy. Sr hampers microstructure refinement when composite Ca/Sr additions are made. In addition, separate Ca additions to AZ91D magnesium alloy increase yield strength but decrease elongation of this alloy. By adjusting the Ca/Sr composite proportions, additions to AZ91D magnesium alloy are able to improve both microstructure and mechanical properties of the alloy.

Effects of Ca combined with Sr additions on microstructure and mechanical properties of AZ91D magnesium alloy

Effect of Rare Earths on Hot Cracking Resistant Property of Mg-Al Alloys

In automotive components, there is a significant weight saving potential in converting to magnesium alloys. Adding Ca element is one of the most effective ways to improve the temperature and mechanical properties of magnesium alloy. However, as hot-cracks often appear in such materials, Ca addition will thus encumber the development of this magnesium alloy. There are few reports on the hot-crack mechanism of magnesium alloy with Ca. This paper focused on the investigations as why to results in the hot-crack phenomenon of Ca addition. These results indicated that Ca addition affects the solidification process of AZ91D alloy, such as elevating the tendency of divorce eutectic and forming the new temperature of Al2Ca phase. In addition, the Ca-contained phase distributed as the net-shape forms on grain boundary and results in lower boundary strength of the liquid film. Both of the above reasons would deteriorate filling capacity of the melt and the hot-crack resistance during solidification stage, resulting in the worst hot-crack property of this alloy.

Bin Tang

Papers

Effects and mechanism of Ca on refinement of AZ91D alloy

Effect of Ca/Sr composite addition into AZ91D alloy on hot-crack mechanism

Effects of Ca combined with Sr additions on microstructure and mechanical properties of AZ91D magnesium alloy

Effect of Rare Earths on Hot Cracking Resistant Property of Mg-Al Alloys

An investigation on hot-crack mechanism of Ca addition into AZ91D alloy