1. Part design
- Use computer-aided design (CAD) software to create a three-dimensional model of the automotive part. The model should be precisely designed according to the function and use requirements of the part, including size, shape, internal structure, etc.
- Consider the force conditions, assembly relationships and lightweight requirements of the part to optimize the design.
2. Process planning
- Select suitable metal materials, such as aluminum alloy, titanium alloy, stainless steel, etc., according to the performance requirements and use environment of the part.
- Determine printing parameters, such as laser power, scanning speed, layer thickness, scanning strategy, etc. These parameters will affect the density, accuracy and mechanical properties of the part.
3. Data preparation
- Convert the designed three-dimensional model into a format suitable for 3D printing equipment, such as STL format.
- Slice the model, that is, cut the model into a series of thin layers along the height direction to generate printing paths and control instructions.
4. Equipment preparation
- Ensure that the powder-spreading metal 3D printing equipment is in normal working condition, and check the laser, optical system, powder supply system, gas protection system, etc.
- Clean the working chamber of the equipment to ensure the cleanliness of the working environment.
5. Printing process
- Spread the selected metal powder evenly on the workbench.
- According to the preset printing path, the laser beam selectively melts the powder to form a layer of cross-sectional shape.
- The workbench drops a layer of thickness, spreads the powder again, melts it, and accumulates layers until the part is printed.
6. Post-processing
- After printing, there will usually be some residual powder on the part, which needs to be cleaned.
- Hot isostatic pressing (HIP) may be required to eliminate internal pores and improve the density and performance of the part.
- Perform mechanical processing such as milling and drilling to achieve the final dimensional accuracy and surface quality requirements.
7. Quality inspection
- Use non-destructive testing methods such as X-ray testing and ultrasonic testing to check whether there are defects inside the part.
- Conduct mechanical property tests, such as tensile tests and hardness tests, to ensure that the parts meet the performance standards of automotive parts.
For example, when printing a car engine cylinder block, the structural strength and heat dissipation requirements of the cylinder block should be fully considered during the design, and high-temperature resistant and high-strength metal materials, such as titanium alloys, should be selected. During the printing process, the laser power and scanning speed are strictly controlled to ensure the density and precision of the cylinder block. After printing, the cylinder block is processed by HIP and machining to achieve the size and performance required by the design, and finally undergoes strict quality inspection to ensure that it can operate reliably in the car engine.
It should be noted that the entire printing process requires strict quality control and process optimization to ensure that the printed automotive parts meet the performance and quality requirements.
