Use of image correlation to monitor the deformation behaviour of ship propellers during additive manufacturing using build-up welding

Traditionally, ship propellers are manufactured by sand-casting with slight oversizing and then milled or ground to the final shape. However, that manufacturing process, particularly in the production of small-diameter propellers (D < 5 m), can only partially be used competitively by the European industry in today´s market. A new method of manufacturing propellers is therefore needed.
Additive manufacturing technology is already well established in the design and manufacture of marine systems. This article presents a means of monitoring the WAAM of propellers using image correlation methods. The GOM ARAMIS optical measurement system is used for its area measurement capability. The method is applied to two test series, one with flat steel plates and one with a ship propeller blade, using different welding materials.