Report: How lighter vehicle components are driving technology in the automotive sector
An update on aluminum, magnesium & steel.
By Mikko Järvikivi
Rapid changes across the automotive supply chain is being driven by tough legislation, carbon emissions and fierce competition.
While CO2 emissions are falling, reducing vehicle weight remains an important priority for the automotive sector with manufacturers working hard to optimize fuel and battery usage in the case of electric vehicles.
The obvious and longstanding answer to these industry trends is to reduce vehicle weight by using lighter components. Achieving this goal brings brings challenges when it comes to materials and quality control.
There are four key technologies taking place with vehicle material components. In this article, we will focus on technologies that enable the sector to meet material quality requirements – especially those that analyze new alloys, aluminum, magnesium and steel (e.g. super-lightweight steel).
The driving force behind change
The big driver behind automotive evolution is the environment. Current legislation aimed at reducing emissions is propelling innovation in the materials used for car components and as global standards get more stringent, the pace of change is quickening.
In Europe, for example, a key European standard responsible for driving change is Euro 6. It aims to ensure average CO2 emissions of new cars are a maximum of 57.44 mpg by 2021. Most manufacturers are now developing electric powertrain technology and striving to reduce weight in response.
Another example is in China where standards have become more stringent, too. China 6a, compliant with European emission standards, is set to come into force in 2020, with a further standard due in 2023. The proposed standards will reduce CO2 emissions by more than 90 percent.
Similarly, with 75 percent of carbon monoxide pollution in the U.S. attributed to motor vehicles, the Environmental Protection Agency announced in January 2020 that it’s working on new rules to decrease vehicle emissions and cars are set to get lighter, following the global example.
The automotive industry and its supply chain, therefore, need to work collaboratively to deliver materials innovations to the industry to make cars lighter.
The role of new alloys
The automotive industry has very specific requirements for components. Safety is obviously a priority and many components must be ductile to absorb energy on impact, while other parts must have strength to maintain structural rigidity.
The development of new alloys is a very exact science and analyzing their chemistry down to the parts per million level is crucial to avoid residual elements, which can impact on the properties of the alloy. Aluminum and magnesium alloys have won favor in the industry because they are light, relatively low cost and provide many of the properties needed. They can be formed into complex shapes including engine components, gearbox housings and structural parts. In fact, the global market for these parts is predicted to grow at a compound annual growth of almost 7 percent to a market size of $48 billion by 2021.
Weighing about one-third less than steel, aluminum’s use in cars has skyrocketed in recent years. In 2018, BMW won an award for a concept to reduce the weight of the tailgate in its 5 Series model. By using aluminum in place of deep-drawn steel sheets, BMW reduced the tailgate from approximately 54 pounds to 25 pounds. By 2022, the average car is expected to contain almost 220 pounds of aluminum as a replacement of heavier parts. The automotive industry will make up a quarter of all aluminum consumption by 2025.
However, to substantially increase the strength of aluminum, you need to add lithium. The third generation of Al–Li alloys could become integral to various components of luxury cars, combining low density, strength, stiffness and damage tolerance.
Magnesium is lighter than aluminum and has the highest strength to weight ratio of all structural metals. It’s abundant and easily recyclable, so it’s not surprising that it has replaced steel and aluminum in building and been used extensively in alloys with aluminum.
Magnesium does have drawbacks: it’s brittle and doesn’t have the creep resistance of aluminum. However, innovations could see that problem resolved. A team at Monash University in Australia has created a process to change the microstructure of magnesium so it can be compressed to any shape at room temperature without cracking. The U.S. Department of Energy has also developed a process that improves the energy absorption and ductility of magnesium, making it more feasible for a larger range of car parts.
Many steelmakers are developing a super-lightweight steel that is stronger, cheaper and almost as lightweight as aluminum in a bid to regain market share. It’s going to be hard to resist the allure of greater strength and lower cost, with new products expected on the market in 2021.
In five years, it’s likely that vehicles will use a larger range of materials than ever before. Therefore, the need to use the right material for the right component and verification of material grade composition will be paramount.
Many foundries already use an analyzer at the time of dispatch. Inspection when raw materials arrive and then again on the factory floor is equally valuable. It is becoming increasingly important to ensure teams have portable tools such as XRF and LIBS or high performance OES on hand for materials analysis and quality checking to verify material grades before raw material enters production stream.
The automotive sector is the largest manufacturing sector in the U.S. It makes up a huge 3 percent of its Gross Domestic Product (GDP). In the past five years, car manufacturers have exported more than $692 billion in cars and car parts. Moreover, when it comes to purchasing American products and materials, the sector purchases colossal amounts of steel, iron and semiconductors.
What’s more, within the U.S. there’s a strong trend towards 100 percent positive material identification by checking, double checking and triple checking for the correct material composition to avoid material mix-ups and product failures. We’re seeing more companies invest in tools to improve quality control processes in the pursuit of 100 percent quality.
In the case of raw materials and metal components, companies are also relying less on supplier certificates and more on investing in analyzers to support them with quality control. As a result, it makes it crucial for firms to prioritize materials analysis and quality control as they develop lighter vehicles.
About the author
Mikko Järvikivi is the head of Global Product Management at Hitachi High-Tech Analytical Science. With 15 years of experience in material analysis and handheld instruments, Järvikivi holds a M.Sc (Tech.) in Chemical Engineering from Aalto University in Finland.
About Hitachi High-Tech Analytical Science
For over 45 years, Hitachi High-Tech Analytical Science has specialized in high-tech analysis solutions designed to meet the tough challenges of a rapidly evolving industrial sector. Today, we’re helping thousands of businesses streamline their costs, minimise risk and increase production efficiency. Our range of laboratory-based and robust high-performance in-field testing instruments deliver materials and coatings analysis that adds value throughout the production lifecycle, from raw material exploration to incoming inspection, production and quality control to recycling. Working in close collaboration with our customers, our in-house experts have developed customised testing methodologies for hundreds of industrial applications, delivering simplicity of operation for even the most demanding applications. We transform the latest technological advances into analysis solutions that drive business success.