Additive manufacturing stabilizes hydrogen intake system for Alpine’s Hy6 prototype

In an early development phase, Alpine combined additively manufactured polymer components with bonded aluminum flanges. However, test-bench runs quickly revealed weaknesses in this approach. Differences in coefficients of thermal expansion, vibrations, and high thermal loads led to sealing problems that could not be reliably controlled under realistic operating conditions. For an engine operating under boost pressure, this represented a significant development risk.

CRP Technology subsequently proposed a fully monolithic design manufactured using selective laser sintering. The material used was the carbon-fiber-reinforced thermoplastic Windform SP. By integrating the flanges directly into the printed geometry, metallic add-on components were eliminated entirely, resulting in homogeneous material behavior across the entire part. The final assembly consists of an intake plenum and two intake runners that do not require any additional joints.

After the SLS process, the internal flow channels were post-processed using vapor smoothing to reduce surface roughness. This was followed by precise CNC machining at CRP Meccanica to ensure dimensional accuracy at interfaces and reliable sealing surfaces. This hybrid approach combining additive and subtractive manufacturing is well established within the CRP Group.

The intake system passed test-bench validation with pressure cycles of up to 5 bar and was subsequently tested on track in the Alpenglow Hy6. For Alpine, this means an accelerated development of the hydrogen powertrain, with 3D printing serving not only as a prototyping tool, but as a function-critical manufacturing technology.