As the global automotive industry accelerates its shift toward “low-carbonization and high-efficiency,” lightweighting has evolved from an “optional upgrade” to a “must-answer question.” Data shows that for every 10% reduction in vehicle weight, fuel efficiency of internal combustion engine (ICE) vehicles improves by 6%-8%, and the range of new energy vehicles (NEVs) increases by 5%-10%. This conclusion has become a core driver for technological innovation in the industry. In this lightweighting revolution, the engine—often called the “heart” of a car—directly determines vehicle performance and environmental performance through its weight reduction 成效. As the core load-bearing components of the engine, the cylinder block and cylinder head have become the top priorities in lightweighting research and development.
Automotive Lightweighting: An Inevitable Choice Driven by Both Policies and Markets
The urgency of automotive lightweighting stems from the tightening of global environmental regulations and the transformation of energy structures. China’s “dual-carbon” goals clearly require NEV penetration to reach 50% by 2030, while traditional ICE vehicles face pre-research pressure for China’s National VII emission standards. Weight reduction has thus become a direct path to lower emissions.
Globally, the EU’s Euro 7 standards (expected to take effect in 2025) will further restrict pollutant emissions, while the U.S. EPA’s stricter fuel economy regulations (CAFE standards) push automakers to cut vehicle weight to meet efficiency targets. Market demand also plays a key role: NEV consumers prioritize range, making lightweighting a critical factor in purchasing decisions, while commercial vehicle operators focus on fuel savings from weight reduction to improve profitability.
Engine Lightweighting: The “Core Engine” for Vehicle Performance Improvement
As the heaviest core component of a car, the engine’s lightweighting has a “multiplier effect” on overall vehicle performance. Traditional ICE engines account for 15%-20% of a vehicle’s total weight. A 10% weight reduction through lightweighting design not only reduces mechanical losses but also optimizes front-rear weight distribution, enhancing steering precision and handling stability.
From a technical perspective, the value of engine lightweighting lies in three dimensions:
- According to Newton’s second law of motion, under the same traction, a lighter engine improves vehicle acceleration performance.
- Lightweighting reduces friction in moving parts and pumping losses: every 1kg reduction in engine weight lowers fuel consumption by 0.1-0.2L per 100km.
- Lightweighting often involves material upgrades and structural optimization: aluminum alloy cylinder blocks, for example, offer 30% higher heat dissipation efficiency than traditional cast iron blocks, effectively improving engine thermal management.
Cylinder Block & Cylinder Head: The “Main Battlefield” of Engine Lightweighting
In the pursuit of engine lightweighting, reducing the weight of the cylinder block and cylinder head is a core breakthrough—together, they account for over 60% of the engine’s total weight, and optimizing their materials and structures directly determines weight reduction outcomes.
Material Substitution: Aluminum Alloy Leads the Charge
Traditional engine cylinder blocks and heads are mostly made of gray cast iron, with a density of approximately 7.2g/cm³. In contrast, aluminum alloy has a density of only 2.7g/cm³—adopting aluminum alloy can achieve a weight reduction of over 30%.
Aluminum alloy’s advantages extend beyond weight reduction:
- Its thermal expansion coefficient better matches that of the piston, maintaining combustion chamber sealing and improving combustion efficiency by 5%-8%, which in turn reduces nitrogen oxide emissions by about 5%.
- Aluminum alloy has a recycling rate of over 90%, far exceeding steel’s 60%, aligning with circular economy goals.
Structural Optimization: Removing “Redundancy” Without Sacrificing Strength
Beyond material substitution, structural optimization technologies also deliver significant results. Through topology optimization—using algorithms to identify and remove redundant material in the cylinder head—engineers can achieve 12%-15% weight reduction while maintaining structural strength.
For example, optimizing the water jacket and oil passage layout in the cylinder head not only reduces unnecessary material but also improves coolant flow, enhancing heat dissipation. Similarly, thinning the cylinder head deck (the surface mating with the cylinder block) by 1-2mm, combined with high-strength aluminum alloys, can cut weight without compromising pressure resistance.
The Balancing Act: Weight, Strength, and Heat Resistance
Cylinder block and head lightweighting is far from a simple “weight reduction at any cost”—it requires balancing weight, strength, and heat resistance. During operation, the cylinder head endures combustion temperatures exceeding 1500°C and burst pressures of dozens of MPa. Thus, lightweight materials must offer excellent mechanical properties and thermal stability. This technical challenge is the core focus of industry R&D.
Heda Aluminum: A “Hidden Champion” Exploring Cylinder Head Lightweighting
As a national high-tech enterprise with over 30 years of experience in engine cylinder head manufacturing, Zhejiang Heda Aluminum has also embarked on a lightweighting journey.
From “Manual to Automated”—Laying the Foundation for Precision Manufacturing
“Traditional production methods are destined to be eliminated; lightweighting is key to Heda’s competitiveness,” notes Wu Bin, General Manager of Heda Aluminum. This insight led the company to launch a “machine replacement” strategy as early as 2010, reducing human error through automated production lines and laying the groundwork for precision manufacturing of lightweight products.
In practice, a single production line achieved an efficiency boost of “1 person replacing 6 people.” More importantly, automated production provided stable manufacturing support for material upgrades and process optimization—critical for maintaining consistency in high-strength aluminum alloy cylinder heads.
Dual-Pronged R&D: Materials and Structures
Heda Aluminum has integrated lightweighting R&D into its core strategy, focusing on two key areas:
- Material Formulation Optimization: Adjusting the ratio of silicon and magnesium in aluminum alloys to enhance material strength, ensuring the cylinder head meets high-temperature and high-pressure operating requirements while reducing weight.
- Structural Innovation: Introducing finite element analysis (FEA) and topology optimization to redesign the cylinder head’s intake/exhaust ports and combustion chamber, removing redundant material while optimizing heat dissipation paths.
Rigorous Testing: “Precision Lightweighting” That Doesn’t Compromise Quality
In Heda Aluminum’s laboratory, every lightweight cylinder head undergoes strict performance testing:
- Air tightness testing requires leakage to be controlled within 0.5kPa/min.
- Sag error must not exceed 0.03mm.
This “precision lightweighting” philosophy—reducing weight without sacrificing quality—is why Heda Aluminum has become a trusted supplier to renowned enterprises like Changchai (a leading Chinese engine manufacturer).
Conclusion: Lightweighting as a Journey of Systematic Innovation
From the automotive industry’s lightweighting wave to core engine technology upgrades, and finally to cylinder head material and structural innovation, the path to lightweighting is long and challenging. Heda Aluminum’s exploration demonstrates that true lightweighting is not a simple material replacement but a systematic innovation based on manufacturing experience, technical accumulation, and market demand.
In this industry transformation that shapes the future, such perseverance and breakthroughs are vivid examples of high-quality development in China’s manufacturing sector