Introduction to the application of magnesium alloy in the automotive field

Editor: Yang Daxin Technology

Magnesium alloys used as automotive components have the following advantages: ① Weight reduction can increase the vehicle's loading capacity and payload, while also improving braking and acceleration performance; ② Magnesium alloy die-casting parts have the advantage of one-time molding, which can combine multiple components to form components in one go, greatly improving productivity and component integration, reducing processing and assembly costs, improving automotive design flexibility, and reducing manufacturing and assembly errors; ③ Magnesium alloys have excellent deformation and energy absorption energy and force. The use of high plasticity magnesium alloys can improve the vibration and collision resistance of automobiles, improve their stiffness, and greatly enhance their safety performance; ④ It can improve the recycling rate of waste parts. Data shows that the recycling of magnesium alloys does not affect the material's performance. Moreover, the energy consumption of regenerated magnesium is low, only a few percent of the energy consumption from ore smelting, which is very beneficial for environmental protection and resource conservation; ⑤ Improve comprehensive fuel economy standards, reduce exhaust emissions and fuel costs; ⑥ Magnesium alloy materials have high vibration absorption and better damping ability than aluminum and steel. Therefore, for some parts of automobiles that perform repetitive or intermittent movements, using magnesium alloy materials can absorb vibrations and extend their service life. Magnesium alloy, as the lightest structural metal in practical applications, can meet the increasingly strict energy-saving and exhaust emission requirements of the automotive industry, thus producing a new generation of transportation vehicles that are lightweight, fuel-efficient, and environmentally friendly.

The vast majority of magnesium alloy parts used in automobiles are die-casting parts, which have significant effects on reducing automobile quality, improving fuel economy, protecting the environment, enhancing safety and driving performance, and strengthening competitiveness. They have great potential for application in the automotive industry. At present, the main applications of magnesium alloys in automobiles are parts such as shells and brackets. Using magnesium alloy to manufacture shell parts can not only reduce weight, but also lower the noise during vehicle operation due to the strong damping and attenuation ability of magnesium alloy.

At present, various automobile companies produce housing parts such as crankcases, cylinder boxes, transmission shaft housings, gearbox housings, clutch housings, filter housings, valve covers, valve plates, and cab instrument panels. Although magnesium alloys currently used in commercial applications cannot be used as strong load-bearing components in automobiles, they are capable of handling secondary load-bearing structural components such as steering wheels, fan frames, steering brackets, mudguard brackets, brake brackets, light brackets, brake and clutch pedal brackets, seat frames, wheel hubs, etc.

Magnesium alloy, as a structural component, also has outstanding advantages. Due to its high specific strength, it can achieve high strength under the same mass, and has good damping performance and high impact toughness. It is particularly suitable for manufacturing components that are frequently subjected to impact. If the steering shaft often bears large torque, and the seat frame and wheel hub are subjected to impact for a long time, the use of magnesium alloy with good damping not only reduces the weight of the car, but also improves the smoothness and safety of the car during driving. So far, magnesium alloy automotive components that have been developed and applied, as shown in the following figure, have been widely used in automobiles, especially in high-end sedans and "special-purpose vehicles". The amount of magnesium used in large displacement vehicles is also showing an increasing trend. In sports cars, vans, SUVs and other vehicle models, although the cost of magnesium parts is relatively high, its lightweight can offset the disadvantage of high cost.

At present, the application status of magnesium alloys in the automotive industry varies between 0.5-17 kg per vehicle, with an average usage of 3kg per vehicle. Volkswagen Passat currently uses 14 kg of magnesium, accounting for 1% of the vehicle weight, and may soon increase to 30-50 kg. Magnesium alloys are mainly used in the driving equipment and internal structural components of Volkswagen's vehicles. With the development of technology, the number of applications of magnesium alloy structural components will increase. The total amount of magnesium alloy die-casting parts used in Audi A6 sedan bicycles has reached 14.2kg, and its future goal is to increase the total amount of magnesium alloy used in bicycles to 50 "-80kg. General Motors and Ford Motor Company expect to increase the magnesium alloy consumption per car from the current 3 kg to 100 kg in the next 20 years. In April 2004, Volkswagen officially launched its newly developed super economy sedan, which is a mini model with fuel efficiency of less than 1 L per 100 km. This model is also an extension of Volkswagen's "Beetle" model.

After comparing materials and processes, it can be seen that magnesium alloys bring lightweighting to automobiles, simplify manufacturing processes, and reduce production costs. In terms of performance, the use of magnesium alloy has brought great advantages to the fatigue durability of the vehicle body. Therefore, the advantages and prospects of magnesium alloy materials are reflected from various aspects, which is a good choice for the development of automotive lightweighting.