Fabrication of optimized transducer head masses via additive manufacturing

The Applied Research Laboratory conducted an investigation into additive manufacturing (AM) as an avenue to improve transducer head mass performance. Techniques, such as powder bed fusion (PBF) of metals and direct ink writing (DIW) of ceramics, offer benefits, including increased design freedom and faster design iteration. The transducer head mass acts as an acoustic radiator and receiver, and is required to have a high stiffness-to-weight ratio. Aluminum is commonly used for this application due to a balance between performance and cost. AlSi10Mg, an aluminum alloy, is readily printed via PBF, making it an excellent candidate for geometric optimization. A technique known as topology optimization has been used to great effect, reducing weight of the part and bridging the performance gap between aluminum and AlBeMet. High performance composites and ceramics are sometimes used for head masses, however their high price and long turnaround time often eliminate them as an option. Recently, DIW has been used to manufacture boron carbide head masses. DIW reduces the need for expensive machining, reducing the cost and time required to employ such a high performance material. This presentation will discuss the optimization of the transducer head mass, including topology optimization of AlSi10Mg and DIW of B4C.