Production of the cylinder head and crankcase of a small internal combustion engine using metal laser powder bed fusion

Abstract

This effort investigates the use of metal additive manufacturing, specifically laser powder bed fusion (LPBF) for the automotive and defense industries by demonstrating its feasibility to produce working internal combustion (IC) engine components. Through reverse engineering, model modifications, parameter selection, build layout optimization, and support structure design, the production of a titanium crankcase and aluminum cylinder head for a small IC engine was made possible. Computed tomography (CT) scans were subsequently used to quantify whether defects such as cracks, geometric deviations, and porosity were present or critical. Once viability of the parts was established, machining and other post-possessing were completed to create functional parts. Final X-ray CT and micro-CT results showed all critical features fell within ±0.127 mm of the original equipment manufacturer (OEM) parts. This allowed reassembly of the engine without any issues hindering later successful operation. Furthermore, the LPBF parts had significantly reduced porosity percentages, potentially making them more robust than their cast counterparts.