Motorsports, and Formula 1 in particular, is considered one of the driving segments for AM adoption. But one thing is the ability to rapidly produce lighter AM car parts and an entirely different thing, especially in F1, is the ability to actually use them. That’s because the regulations for additive manufacturing in Formula 1 are very (very) strict and sometimes block AM materials and applications.
These limitations don’t apply to prototyping, of course. You can do a lot of that with AM, even directly on the track. Production requirements are stricter. That’s actually strange because in many cases AM could reduce production costs and make innovative teams with smaller economic possibilities more competitive. In fact, that seems to be what the F1 wanted to achieve by introducing a salary cap in 2021. But the reality of it is a bit more complex.
What can you 3D print in an F1 car?
You cannot use AM on the core of primary heat exchangers
This seems a bit of a paradox but it actually says so in section 7.4.3 of the 2021 Formula 1 Technical Regulation. This is where the F1 gives indications on “Primary heat exchanger specification and technology”. In order to reduce the cost of primary heat exchangers used in the car (there are usually the components that hold the fluids), the following restrictions apply: (a). the core and header tanks must be made from aluminum alloy and (b) the core must not be produced using additive manufacturing.
So yes, you can use aluminum but no, you cannot 3D print it the core of the heat exchanger. This is quite curious. Since the introduction of the hybrid power units, engines need less cooling overall, however, more parts need to be cooled. Perhaps the FIA feels at this time that, in this case, having more money means having greater access to AM technologies and thus a greater advantage over other teams. However, this point could probably be reviewed in the future.
You can use a fairly wide selection of metal materials for AM
Section 15.3.2 details the “Metallic Materials Used for Additive Manufacture”, including two recent additions from APWORKS and Elementum. Components produced by additive manufacturing can be made from materials in the following list:
- Aluminum Alloys; AlSi10Mg, AlSi7MG, Al Cl-30AL
- Aluminum Alloys with particulate reinforcing, A20X, 2024-RAM2%, 6061-RAM2%
- Aluminum-Magnesium Alloys; Scalmalloy
- Titanium Alloys; Grade 1, Grade 2, Ti6Al4V, Ti 5553, Ti 6242
- Steel Alloys; 316, 304, MS1, 15-5PH, 17-4PH, 300M, 4140
- Copper Alloys not containing Beryllium
- Superalloys; Inconel 625, Inconel 718, Cobalt-Chrome
This is actually quite an extensive list which is fairly regularly updated. However you also need to keep in mind that: “the finished mass of a component made by additive manufacturing should be no less than 60% of the mass of the printed component, excluding support structures.”
Section 15.4 discusses Specific Prohibitions. One refers specifically to AM – forbidding the use of beryllium – however a few the other ones also indirectly pertain to AM. Here they are:
- Metal Matrix Composites, except where allowed under article 15.3.2
- Shape Memory Materials except for piezoelectric materials used in electrical sensors
- Titanium alloys may not be used for fasteners with a male thread less than 15mm diameter
- Alloys where the combined weight of Platinum, Ruthenium, Iridium, Rhenium and Gold is more than 5%
- Components produced by foil metallurgy
- Intermetallic alloys
- Additive manufactured materials containing Beryllium
Composites and ceramics
These families of materials are not necessarily linked with AM but they are advanced materials that could leverage some AM process. This is what FIA regulations say about using them in F1.
With respect to “Reciprocating and rotating components”: section 5.18 says that reciprocating and rotating components must not be manufactured from a graphitic matrix, metal matrix composites or ceramic materials, this restriction does not apply to the clutch and any seals. With respect to static components: “other than inserts within them, engine crankcases including sump, cylinder heads and cylinder head cam covers must be manufactured from aluminium or iron alloys. No composite materials or metal matrix composites are permitted either for the whole component or locally.”
Carbon-carbon composites may, however, be used for friction materials. Rolling elements of rolling element bearings must be manufactured from an iron-based alloy or from a ceramic material. All timing gears between the crankshaft and camshafts (including hubs) must be manufactured from an iron-based alloy. High-pressure fuel pump elements may be manufactured from ceramic material.
All threaded fasteners must be manufactured from an alloy based on Cobalt, Iron or Nickel. Exceptions include fasteners whose primary function requires them to be an electrical insulator: these may be manufactured from ceramic or polymeric materials.
Among the other exceptions, monolithic ceramic Materials may be used for rolling elements, rolling-element bearings, high-pressure fuel pump elements, electrical components, thermal insulation, clutch friction materials and spherical bearings. Ceramic matrix composites may be used for friction materials, seals and thermal insulation.
Author: Davide Sher – Founder & CEO at 3dpbm