In 2023, Walk into the HiPhi Y body engineering team
Integrated die-casting research and development leads Chinese auto brands
When it comes to the body, everyone’s first reaction is to be “tough”, so that the car is safe enough.
With the development and research of new technologies, new processes, and new materials, the body must not only be safe and durable, but also meet the requirements of energy saving and comfort.
For the HiPhi Y body engineering team, there is a direction, and the difficult ones are the questions they set for themselves.
The backbone of the body engineering team is almost all from domestic first-class OEMs.
Most members have more than 15 years of experience in forward design and development of body engineering, and have led the development of many popular models of joint ventures and independent brands.
In the past, they used to spend two and a half years to put together thousands of parts and nearly a hundred assemblies.
But in HiPhi, they face more stringent standards and requirements.
For example, the new battleship HiPhi Y needs to adjust the pace of R&D and production, and reduce the internal connections of components.
Under such great pressure and challenges, the team faced up to the difficulties, so the first domestic mass-produced 7,200-ton integrated die-casting rear cabin project came into being.
When designing a body casting, the traditional thinking needs to give priority to the carrying capacity of the market, such as the maximum tonnage of the equipment and the maximum size of the parts that can be die-cast.
But HiPhi is different. The body engineering team reversely deduces what equipment, tooling and materials are needed according to its own integration needs, and then develops new equipment, molds, tooling, materials and new processes with suppliers.
The HiPhi Y model equipped with super-large castings was made clear at the beginning of the project: the whole vehicle is developed in accordance with the more demanding three-party evaluation system (NCAP) 5-star ultra-high-performance structural crashworthiness, providing passengers with all-round safety protection.
With the high requirements of the whole vehicle, the body engineering team chose to integrate and optimize the development of more than 40 parts in the rear cabin with complex structures, numerous interfaces, and high integration requirements.
Oversized castings that integrate important mounting points such as seats, batteries, and shock absorbers.
There are no off-the-shelf fasteners to choose from, so create your own.
How to establish a solid and reliable connection with the surrounding parts, there is no experience to continue to use, the body engineering team is working on key problems from product process design, deviation analysis and physical verification, and finally developed more than 130 content items and overcome more than 20 key points After solving the problem, complete the patented technology reserve and mass production.
At the same time, the body engineering team also cooperated with the virtual simulation team to optimize the outline of the large casting in the rear cabin with multi-objective conditions.
In order to pursue the ultimate simulation accuracy, the virtual simulation team’s model meshes were partially refined to the 1mm level, and the number of large casting meshes reached an astonishing 9 million, and the number of calculation iterations was astonishing.
In order to cover all possible road conditions, the real vehicle has carried out comprehensive load collection in multiple road conditions, and the load has been amplified with a 20% safety margin.
Enter an adult elephant for testing.
Under the integrated design, the rigidity of HiPhi Y’s body structure is far higher than that of the same type of structure.
By using heat-free treatment materials and high-pressure die-casting, the weight of the rear cabin can be reduced by as much as 20%, truly realizing “light as a swallow”.
The “congenital” yield rate of integrated die-casting is relatively low.
There are too many “hurdles” to go through in the whole process: material science, structural mechanics, mold design, cooling model, and a large amount of data must be monitored in real time during the production process.
At the same time, injection speed, injection pressure, mold thermal balance, temperature field, and high speed The quality and stability of the product can be guaranteed by the cooperation of time, filling time, pressure holding time, etc.
In addition, the model is often deformed due to thermal expansion and contraction.
Therefore, the body engineering team is also very particular about the design of the sprue position of the entire product.
Designing the sprue in the middle of the product not only ensures the balance of the performance of each area of the entire product and the full flow of materials, but also combines the casting after the mold is released.
The advanced cooling process can make each part cool evenly and the deformation is small.
Innovative materials
The integrated ultra-large die-casting technology puts forward higher requirements for materials.
The development of high strength materials that do not require heat treatment is key for large die casting applications.
Among the permutations and combinations of dozens of aluminum alloy materials and ultra-multiple trace elements, the material team screened them almost exhaustively: from small test pieces of tens of millimeters to half-meter shock towers, to one-meter Multiple sub-frames, etc. are verified step by step.
In the end, the body engineering team and Shanghai Jiaotong University Light Alloy National Engineering Center joined forces to successfully launch TechCast, a new low-carbon aluminum alloy material.
It has excellent performance in die-casting performance, mechanical performance, manufacturing process, environmental durability, vehicle collision and other indicators.
Among them, the casting fluidity is more than 15% higher than the same level of materials, and the strength and plasticity are more than 30% higher, reaching the international leading level.
After multiple rounds of design optimization iterations and physical test verification, the first domestic project based on the forward development of a 7,200-ton giant die-casting machine and the integrated super-large die-casting body rear cabin project was successfully launched and mass-produced half a year later.
The integrated high-pressure die-casting rear cockpit of Human Horizons has successively won the 10th Altair Enlighten Award for lightweight enabling technology, and the 2023 2nd International Green Zero-Carbon Festival Carbon Neutrality Outstanding Case Award, which has been highly recognized both inside and outside the industry.
“This super-large casting product is domestically produced from the core process of materials, molds, presses, and engineering research and development.
This is our own industrial artwork.
I think this product can be called the light of domestic products.” said the head of the body engineering team proudly.
Faced with challenges and difficulties, the body engineering team directly gave their answer, that is, No Fear.
