In simple terms, lightweight design is the act of reducing the amount of material in a component to lower its overall weight without sacrificing reliability or function.
Governments and consumers are demanding that industries across a range of sectors reduce their energy consumption and their greenhouse gas emissions. Lightweight design is set to provide manufacturers with the solutions they need to take on the challenges posed by climate change while also achieving better component performance and enhancing product lifespans.
This is most predominantly seen in the automotive and aerospace industries where lightweight design has led to improvements in fuel efficiency and better performance in both aircraft and electric vehicles. However, it should be noted that lightweight design is also driving innovation in the construction industry, renewable energy, and in the manufacturing of electrical and electronic goods. Lighter components have resulted in reduced transportation and energy costs as well as more resource-efficient production methods across all these sectors.
The considerable environmental and economic benefits in pursuing innovation in lightweight design ensures that it will continue to be a crucial area of investment and research for many industries now and in the years to come.
Popular Materials for Lightweight Design
Aluminum Alloys
Aluminum is used widely in the automotive industry for its lightweight properties. Auto industry analysts have stated that using aluminum parts can result in up to a 50 % reduction in vehicle weight without sacrificing safety or performance. Aluminum’s malleability, durability, and lightness also makes it a popular material for manufacturing consumer goods, electronic products, and aircraft.
A report from DuckerFrontier, the 2020 North American Light Vehicle Aluminum Content and Outlook, predicts that aluminum use in the USA car market is expected to reach over 233 kilos per vehicle by 2026. This is an increase of 12 % from 2020 levels. Global aluminum consumption is predicted to reach 64.2 million metric tons by the end of 2021.
As the trend towards hybrid and electric vehicles continues, automakers will continue to see aluminum as a preferred material due to its low cost, high performance and exceptional weight saving properties.
Magnesium Alloys
33 % lighter than aluminum, 50 % lighter than titanium, and 75 % lighter than steel, magnesium alloys are proving to be a valuable material for lightweight design engineers. Magnesium can easily be machined, has good structural strength, and is used widely in the automotive and aerospace industries as well as to manufacture consumer products
Its low density and high specific strength mean that magnesium is utilized as a lightweight component in everything from aircraft to missiles to laptop computers and televisions. As well as components and structural elements, magnesium-based batteries are currently being developed for use in the automotive industry
An analysis from the US Automotive Material Partnership stated that 113 kilos of magnesium can be used to replace 226 kilos of steel. 40 kilos of magnesium can be used to replace 68 kilos of aluminum. This results in a reduction of 15 % in overall vehicle weight
China has plans to increase the amount of magnesium components used in automobile production to up to 45 kilograms per vehicle by 2030.
The global magnesium market was valued at USD 4,115.0 million in 2019 and is projected to reach USD 5,928.1 million by 2027. China produces approximately 85 % of the world’s magnesium. However, recent smelter closures are resulting in shortages of magnesium sparking concerns about supply and inflation.
Titanium Alloys
Titanium is highly resistant to corrosion, is anti-magnetic, provides good shielding against electrical and electromagnetic fields, is resistant against extreme temperatures, and has a higher tensile strength than steel while being only half the weight.
There have been huge advancements in the production of titanium alloys in recent years. They are now being used to manufacture products such as turbine blades, aircraft frames, resistors, circuit boards, and surgical instruments. The automotive industry manufactures lightweight titanium exhaust systems, engines, transmissions, and frames.
Titanium Alloys
Titanium is highly resistant to corrosion, is anti-magnetic, provides good shielding against electrical and electromagnetic fields, is resistant against extreme temperatures, and has a higher tensile strength than steel while being only half the weight.
There have been huge advancements in the production of titanium alloys in recent years. They are now being used to manufacture products such as turbine blades, aircraft frames, resistors, circuit boards, and surgical instruments. The automotive industry manufactures lightweight titanium exhaust systems, engines, transmissions, and frames.
Innovations In Lightweight Design and Manufacturing Technologies
Innovations in manufacturing technologies are begin driven forward as industries scramble to create lighter components to meet their environmental targets.
Rheocasting is now widely replacing thixocasting as companies seek new methods to create low-cost, high-performance components. One of the main advantages of rheocasting, is its ability to cast metal at a wide range of fraction solids. Rheocasting can effectively and economically produce lightweight components that have high strength and good ductility.
Advances in additive manufacturing (3D printing) technology are providing engineers with greater design freedom than ever before. Additive manufacturing can empower manufacturers to create complex geometries at a much lower cost than traditional die casting techniques. Additive manufacturing is also used to reduce component weight by converting solid geometries into hollow structures or by replacing solid structures with internal lattice structures. Indeed, there is now a range of lightweight components that can only be produced using additive manufacturing techniques.
Future Lightweight Solutions
The future of lightweight design will continue to be dominated by the use of aluminum, magnesium, and titanium alloys but will also incorporate composite materials such as carbon or glass fiber reinforced polymers. Many companies are now concentrating on the development of plastics-based hybrid lightweight components for use in the aerospace and automotive industries.
Innovations in computer software and additive manufacturing techniques will allow for the development of even lighter products, parts, and structures. Engineers can achieve maximum topology optimization for a range of components by using specialized software to pinpoint areas where weight reduction can most effectively occur. Digitized 3D models can then test the performance of proposed lightweight parts to identify optimal design options.
Bionic design and biomimicry may point to where the future lays for lightweight design. Engineers and scientists are producing components based on lightweight, multifunctional structures found in nature. Examples of this include the Airbus 2050 concept aircraft which incorporates a fuselage based on bone structures. Recent research efforts have concentrated on the exoskeletons of unicellular planktonic organisms, honeycomb structures, grass stalk structures, and the epidermal cells and wings of butterflies.
By combining the constant search for technological and scientific innovation with a deeper understanding of nature, manufacturers and industries will continue to develop lighter, stronger components that will aid humanity in our common goal to reduce CO2 emissions and combat climate change.
