The automotive industry has always been at the forefront of adopting innovative technologies to enhance vehicle performance, fuel efficiency, and overall driving experience. One such groundbreaking technology that has captured the attention of automotive engineers and designers is 3D printing, also known as additive manufacturing. This transformative manufacturing method allows for the creation of complex and lightweight components, revolutionizing the way automotive engine parts are designed and produced. In this extensive blog post, we will explore the concept of integrated manufacturing of automotive engine components using 3D printing to reduce weight, delving into the benefits, challenges, and real-world applications of this cutting-edge approach.
Understanding Integrated Manufacturing
Integrated manufacturing is a holistic approach that aims to optimize the design, materials, and production processes to achieve specific objectives, such as weight reduction, increased performance, and improved efficiency. In the context of automotive engine components, integrated manufacturing utilizes 3D printing to create lightweight, high-strength parts that seamlessly integrate multiple functions into a single component.
The Role of 3D Printing in Weight Reduction
The traditional manufacturing processes for automotive engine components, such as casting and machining, often result in parts with excess material, leading to increased weight and reduced fuel efficiency. 3D printing, on the other hand, offers a unique advantage in weight reduction by enabling designers to optimize the part’s internal and external structures.
Internal Lattice Structures
One of the key features of 3D printing is its ability to fabricate intricate internal lattice structures within a solid part. These lattice structures significantly reduce the weight of the component while maintaining its structural integrity. The lattice design can be tailored to distribute stresses and loads effectively, ensuring the part’s strength is not compromised.
Topology optimization is another powerful tool in the 3D printing arsenal. It involves using algorithms to determine the ideal distribution of material within a part, resulting in a design that is optimized for its intended application. By eliminating unnecessary material, topology-optimized parts are much lighter, without sacrificing performance or safety.
Real-World Applications of Integrated Manufacturing in Automotive Engine Components
Integrated manufacturing using 3D printing has gained traction in the automotive industry, with several notable applications in engine components. Let’s explore some of these applications and their impact on weight reduction and overall vehicle performance:
1. 3D-Printed Engine Blocks
Traditionally, engine blocks have been manufactured using casting methods, which often result in bulky and heavy components. By employing 3D printing, automotive manufacturers can design engine blocks with internal lattice structures, reducing weight without compromising the block’s structural integrity. The weight reduction contributes to improved fuel efficiency and overall vehicle performance.
2. Lightweight Cylinder Heads
Cylinder heads are critical components of an engine, and their weight directly affects engine performance and fuel efficiency. Through integrated manufacturing using 3D printing, designers can optimize the design of cylinder heads to include internal lattice structures and reduce unnecessary material, resulting in lighter yet durable components.
3. 3D-Printed Pistons
Pistons are subjected to high stresses and temperatures during engine operation. 3D printing allows for the creation of complex and lightweight piston designs that are optimized for strength and thermal performance. The reduced weight of 3D-printed pistons contributes to reduced inertia and friction, enhancing engine responsiveness and fuel efficiency.
4. Lightweight Turbocharger Components
Turbochargers play a crucial role in increasing engine power and efficiency. With 3D printing, manufacturers can create lightweight impellers and turbine components with intricate geometries. The reduced weight of these 3D-printed turbocharger components results in improved turbo response and overall engine performance.
Benefits of Integrated Manufacturing Using 3D Printing
The integrated manufacturing approach, coupled with 3D printing, offers numerous benefits for automotive engine components:
1. Weight Reduction
The primary benefit of integrated manufacturing using 3D printing is weight reduction. By optimizing part designs and incorporating internal lattice structures, significant weight savings can be achieved, leading to improved fuel efficiency and lower emissions.
2. Enhanced Performance
Lightweight engine components contribute to enhanced vehicle performance. Reduced inertia and friction result in better acceleration, responsiveness, and overall driving dynamics.
3. Design Freedom
3D printing provides designers with unparalleled design freedom, allowing them to create complex and intricate geometries that would be challenging or impossible to achieve using traditional manufacturing methods.
Integrated manufacturing with 3D printing enables customization of engine components to suit specific vehicle models or performance requirements. Designers can tailor parts to meet the unique needs of different automotive applications.
5. Faster Prototyping
Prototyping using 3D printing significantly reduces lead times and costs, enabling faster design iterations and validation of new concepts.
Challenges and Future Prospects
While integrated manufacturing using 3D printing presents exciting possibilities, several challenges must be addressed for its widespread adoption:
1. Material Selection and Properties
The range of materials suitable for 3D printing continues to expand, but not all materials may meet the stringent requirements of automotive engine components. Advancements in materials science are needed to offer a broader selection of high-performance materials for 3D printing.
While 3D printing is well-suited for low-volume production and prototyping, scaling up to mass production presents challenges in terms of production speed and cost-effectiveness. Research into faster printing methods and production-scale 3D printers is ongoing to address this limitation.
3. Material Characterization and Certification
Ensuring the reliability and safety of 3D-printed engine components requires rigorous material characterization and certification processes. Standardization and certification bodies play a crucial role in establishing the authority and trustworthiness of 3D-printed automotive parts.
4. Integration with Traditional Manufacturing
Fully transitioning to integrated manufacturing using 3D printing may require the integration of 3D-printed components with conventionally manufactured parts. This integration must be seamless to ensure optimal performance and reliability.
Integrated manufacturing using 3D printing presents a compelling solution to reduce the weight of automotive engine components and enhance vehicle performance. The ability to create lightweight, high-strength parts with intricate internal lattice structures has the potential to revolutionize the automotive industry, driving advancements in fuel efficiency, emission reduction, and overall driving experience.
As the technology continues to evolve, automotive manufacturers, researchers, and designers must collaborate to overcome challenges and unlock the full potential of integrated manufacturing using 3D printing. With a commitment to innovation, material advancements, and efficient scaling, the future of lightweight and high-performance automotive engine components through 3D printing looks promising. Embracing this transformative manufacturing approach will undoubtedly shape the future of automotive engineering and contribute to a more sustainable and efficient automotive landscape.
The petrol and diesel engines of modern passenger cars are of all-aluminium design, with cost and weight optimisation using the latest conventional production techniques. The weight-to-power ratio of these engines has increased progressively in recent years, with mass-to-power ratios of around 1.1 kg/kw for 3- and 4-cylinder engines, reflecting the balance between material properties, load distribution and structural use of the engine for a given production boundary condition. This at the same time means that further significant weight reduction is not possible with conventional production techniques.
In order to further investigate the potential for continued engine weight reduction in the context of new technologies, the German Federal Ministry of Economic Affairs and Energy has launched a research project called LeiMot (Lightweight Engine), which involves several heavyweights in the automotive industry, such as FEV Europe GmbH, Volkswagen, RWTH Aachen University and the Fraunhofer research institute. The project aims to reduce the weight of key engine components through metal 3D printing and new metallic materials, and in August 2020 the project is now in the final engine prototype phase, which is expected to reduce the weight of the latest generation of internal combustion engines by 30% by replacing traditional metal parts with components made from fibre composites and 3D printing technology.
Integrated manufacturing of automotive engine components using 3D printing to reduce weight by 21% and improve powertrain efficiency for mature modern products
The 2.0L turbocharged direct injection diesel engine of Volkswagen’s EA288Evo series was targeted for optimisation due to its high mechanical load capacity, and two components in particular were selected: the cylinder head and the crankcase. Both parts were manufactured using a selective laser melting process, rather than die-cast aluminium as in the past. the high design freedom of 3D printing was used not only to reduce weight but also to improve engine performance. During the development of the LeiMot engine concept, the design boundaries of the components have adhered to the entire process of 3D printing, including support structures, print orientation and post-processing.
The researchers began with a functional decomposition of the cylinder head and crankcase. In this way, the researchers were able to analyse each function and could optimise the design according to the given boundary conditions. In addition, the researchers needed to ensure that the LeiMot cylinder head would be inter-compatible with the VW crankcase. At the same time, the researchers had to retain the important interfaces and components of the reference engine, in particular the crank-link mechanism, the air distribution mechanism and the air change components.
Optimising cylinder heads – achieving structural designs that are not possible with conventional processes
A special design method has enabled the researchers to achieve cooling, lubrication and air exchange functions in a material no thicker than 2 mm, with a lattice structure that is significantly less than 2 mm thick. this method allows a wide range of wall thickness parameters to be used depending on the load and without the structural weaknesses associated with conventional manufacturing.
In the case of cylinder heads, engineers need to reinforce certain areas that are subject to high mechanical stresses, as the combustion process mainly generates bending loads, while the whole engine is subject to torsional loads. The optimum ratio of weight reduction to stiffness was a combination of an I-beam and an integrated closed console. In the end, the structurally optimised AlSi10Mg cylinder head manufactured using selective laser melting 3D printing technology weighed 2.3 kg less, a 22% weight reduction compared to the original part.
The crankcase was also 3D printed and manufactured using AlSi10Mg. Considering the weight and stiffness of the crankcase, it was decided to use a short skirt design with an aluminium base. By reducing the main bearing friction diameter of the bearing housing, it was possible to replace the steel bearing cap with an aluminium plate base. The redesigned crankcase, including the base, has a weight reduction of 5.1 kg compared to the original assembly. By using a topological approach, the researchers have optimised the main flow paths of the assembly and designed cavities and lattice structures for low stress areas such as the outer partition.
For the lightweight design solution, which is close to the limit, the researchers have taken an in-depth look at the material properties during the design process. Due to the special microstructure of the material, there are significant differences between the mechanical properties of parts produced by 3D printing technology and those made by conventional casting processes. The researchers have therefore investigated a number of mechanical properties of 3D printed aluminium alloys at different temperatures using samples and have used the results in their calculations.
In addition, by using 3D printing technology, the researchers have designed a new oil passage solution without significant deflection. The oil passages in the cylinder head and crankcase (diameter range 3-8 mm) can be printed directly. The curved channels and gently varying cross-sections result in a reduction in pressure loss in the internal piping system of the cylinder head and crankcase by approximately 22%.
Thanks to the additive manufacturing approach, the concept engine developed in this project will ultimately be equipped with a minimum number of components, minimising material use through minimal component and high functional integration, resulting in a weight reduction of approximately 21% in the main components of the baseline diesel-powered passenger car, while also improving powertrain efficiency, operational performance, thermal management capabilities and improving vehicle noise, vibration and comfort.
The LeiMot research project is a strong demonstration of the design feasibility of the new manufacturing process. In addition, the project is helping researchers to explore new methods for the development of internal combustion engines. 2021 will see five LeiMot prototypes built by FEV and tested through mechanical and thermodynamic tests.
In the short to medium term, components produced in large quantities through 3D printing technology will still find it difficult to compete with conventional manufacturing processes for the mass market. 3D printing technology has been successfully applied to small components in small production processes such as aircraft component manufacturing. In the future, researchers could also use hybrid solutions that combine 3D printing technology with traditional manufacturing processes to further improve manufacturing quality.