Challenges in Aluminum Metal Injection Molding
Aluminum Powder Surface Oxide Film: The dense oxide film on the surface of aluminum powder hinders the diffusion of atoms between powder particles and the densification process during sintering, making it difficult for aluminum alloys to achieve high density.
Low Melting Point: The relatively low melting point of aluminum alloys makes them susceptible to deformation or damage during high-temperature sintering processes, adding complexity to the manufacturing process.
Advancements in Aluminum Alloy Injection Molding
Aluminum alloy injection molding (AIM) technology has advanced with the development of dedicated equipment by collaborations between domestic machinery manufacturers and universities, aimed at improving production efficiency and automation. Meanwhile, powder injection molding technology, used in military, medical, and consumer electronics, has seen rapid development with materials like iron and stainless steel powders, and significant advancements in aluminum alloy MIM, particularly in lightweight and high-strength applications. In 2021, China initiated a major project, achieving mass production of high-density 6061 aluminum alloy through research on various alloy systems.
Challenges of Traditional Machining Methods for Aluminum Alloy Precision Parts
- CNC Machining: Complex parts take a long time, and machining efficiency is low.
- Aluminum Alloy Die Casting: Difficulties in processing thin-walled products.
Advantages of Aluminum Metal Injection Molding (MIM) Technology
Using the aluminum MIM part radiator as an example, the main reasons for choosing aluminum MIM technology to manufacture radiators are higher thermal conductivity and greater design flexibility compared to extrusion and die casting.
Aluminum MIM Material Properties 6061
6061 alloy is one of the most popular forging alloy grades, renowned for its excellent ductility, extrudability, weldability, machinability, thermal conductivity, electrical conductivity, and corrosion resistance. 6061MIM material composition and its properties introduction:
| MIM 6061 | Sintered | T6 | bar and sheet metal |
|---|---|---|---|
| Density(g/cm²) | 2.68±0.01 | 2.68±0.01 | 2.70-2.73 |
| Vickers hardness(HV) | 50±5 | 105±5 | 86-110 |
| Yield strength(MPa) | 78 | 296 | 55-245 |
| Tensile strength(MPa) | 158 | 335 | 124-265 |
| Elongation( %) | 26 | 6 | 25/8 |
| Electrical conductivity(IACS) | 41.9 | 47/43 | |
| Thermal conductivity W/(m²K) | 136 | 18C | |
| Mirror polishing | OK | OK | OK |
| Salt spray test | 48h | OK | |
| PVD | OK | OK | OK |
| Anodizing | OK | OK | OK |
Application of Aluminum Injection Molding
- Thermal management parts
- Consumer electronics
- Sports equipment
- Household items
FAQ About Aluminum Injection Molding
The performance of MIM aluminum alloys
The performance of MIM aluminum alloys relies on unique raw materials, feedstock, forming, debinding, and sintering processes. With these, we have achieved high density in MIM aluminum alloys while minimizing sintering deformation. Taking 6061 as an example, its sintered density reaches 2.69-2.70g/cm³, with sintering deformation of ±0.05mm for 10mm-sized parts. The hardness is HV50±5, and in the T6 heat-treated state, the yield strength approaches 300MPa, with an elongation rate of no less than 6%.
How is the corrosion resistance of MIM aluminum alloy parts?
Salt spray tests were conducted on sintered MIM 6061 samples, where the surface of the samples that underwent magnetic polishing could pass the 48-hour test.
How is the polishing performance of MIM aluminum alloy parts?
The polishing performance of powder metallurgy components is related to density. Our company’s MIM 6061 aluminum alloy has a density of over 99.5%, resulting in very few and small pores. Through practical testing, the degree of mirror polishing can reach up to 70% of that of the same material sheet.
Can MIM aluminum alloy parts undergo anodizing treatment?
For aluminum alloy parts used as appearance components, anodizing performance is particularly important. We have achieved anodizing treatment for MIM aluminum alloy due to its high density. Currently, red and other colors have been tested successfully.
Consultative Design Services
JunKun Custom Metal Injection Molding Service provides free Consultative Design Services throughout the process. It includes all processes from your design stage to mass-produced finished products.
1.Material Selection Consultation
2.Structural design service
3. Mold design service
4.MIM part manufacturing
Ready to unlock AIM Manufacturing’s potential for your project? Contact us to see how our advanced MIM technology can precisely, strongly, and efficiently turn your designs into reality.
