A. Grevstad, Third Wave Systems, Minneapolis, MN
Given their high strength to weight ratios, titanium and other hard to machine materials have increasingly become materials of choice in efforts to reduce weight of aerospace components. While recent advances in high speed machining (HSM) of aluminum materials have successfully achieved significant reductions in cost of aerospace and automotive structures and components, these advances have not been successfully applied to titanium and nickel-based alloys. Machining costs are a major cost driver in producing these components, so a meaningful increase in metal removal rate capability will have a significant economic benefit. Primary barriers to achieving high metal removal rates of titanium and other hard to machine materials include: 1) lack of validated analytical development tools to reduce dependency on testing trial and error methods, 2) high cost and inefficient methods for testing new machining concepts, 3) inherently different machining characteristics (i.e. material characteristics and behavior during machining) of titanium and other hard to machine materials, and 4) high cost of raw materials. This presentation will demonstrate the application of new and existing modeling technology – both FEM and mechanistic modeling - to cost effectively reduce the first 3 of 4 barriers identified above. This will be accomplished by: 1) use of validated process modeling technology specifically developed for modeling metal cutting, 2) use of process modeling techniques to significantly reduce the need (and cost) for testing while increasing the efficiency and successful implementation of new concepts, and 3) use of validated material modeling technology already developed specifically for machining applications. Industry examples will be presented, from both commercial and military aerospace applications, demonstrating the use of modeling to reduce cycle time, improve tool life and maintain part quality – striking a balance between the three aspects of a machining process to reduce overall costs.
Summary: Application of new and existing technology-both FEM and mechanistic modeling-can cost effectively reduce barriers to achieving high metal removal rates of titanium and other hard to machine materials.
