Improved Titanium Machining Process

While recent advances in high speed machining (HSM) of aluminum materials have successfully achieved significant reductions in cost of aerospace structures, these advances have not been successfully applied to titanium material components. Machining costsare a major cost driver in these components, so a meaningful increase in metal removal rate capability will have a significant economic benefit. Primary barriers to achieve high metal removal rates of titanium include:1) the lack of validated analytical development tools to reduce the dependency on testing trial and error methods,2) the high cost and inefficient methods for testing new machining concepts,3) the inherently different machining characteristics (i.e. material characteristics and behavior during machining) of titanium,4) the high cost of titanium material itself.The focus of this project will be to develop and demonstrate the application of new and existing modeling technology to cost efficiently reduce the first 3 of 4 barriers identified above. This will be accomplished by:1) the use of validated software modeling technology specifically developed for modeling metal cutting, (the same baseline technology which was instrumental in HSM of Al),2) the use of modeling techniques to significantly reduce the need (and cost) for testing while increasing the efficiency and successful implementation of new concepts,3) the use of validated titanium material modeling technology already developed specifically for machining applications.The benefits to be received are:1. The immediate commercial availability of a validated software modeling platform for the analysis and development of titanium cutting processes.2. An easy-to-use modeling environment that can be used for both process modeling and cutting tool development.3. The development of a new validated analytical tool that will significantly reduce the amount of testing trials (and hence, schedule and cost) for developing new cutting methodologies.4. A more fundamental scientific understanding of the titanium cutting process.5. A tool that will provide an affordable research method for analyzing, developing, and evaluating HSM techniques specifically for titanium materials.6. Reduced risk and higher success rates for actual cutting tests that are conducted.Commercial applications include in the broadest sense all machining of titanium components and could very easily be extended into nickel-alloy materials as well. Specifically for the scope of this project, Ti-6Al-4V will be the material of choice. Theprimary application is its' use in aerospace structural and engine components, both commercial and military.Specific applications will include:1. Turning machining processes, including boring, reaming, inside diameter and outside.2. Milling machining processes, including end milling, pocket milling, etc.3. Cutting tool development; geometries, substrates, use of coatings, development of operating specifications, etc.As example, a typical aerospace engine component may cost $150,000 - $250,000 by the time all the machining is performed. Relatively small productivity increases of 10% - 20% in parts of this high cost return large economic benefits. Multiplied byseveral hundred units per year, this easily begins to return millions of dollars in savings for just one component.Likewise the successful application of HSM techniques in titanium may allow HSM to economically replace other less desirable methods such as chemical etching. This could potentially reduce process costs on these same type of components by 50% or more,while also eliminating a hazardous, non-desirable type of process.We believe the applications and potential for economic return is well known by the industry. However, industry lacks the appropriate tools, capability, and fundamental scientific understanding to be able to economically develop and implement the nexthigher order level of capability. Instead choosing to rely on present techniques that mainly are past experience and trial and error testing methods.