The low-pressure turbine for the PW1100G-JM Geared Turbofan™ engine, the engine for the Airbus A320neo, is the first turbine ever to come equipped with borescope bosses produced by additive manufacturing processes. The bosses form part of the turbine case and allow the blading to be inspected at specified intervals for wear and damage using a borescope. MTU used to make these parts by casting or by milling them from the solid. Now they are being manufactured by the SLM process. With this technique, the first step is to slice up a 3D CAD model of the component to be produced. A laser then builds up the solid equivalent of the model layer by layer from a powdered material, the layer thickness being 20 to 40 micrometers. The powder particles are locally melted and fused together.

• Production part
• Selective laser melting (SLM), Inconel 718