Boeing has launched two new projects for the manufacturing of hypersonic vehicles – those that exceed Mach 5, or around 3,800 miles per hour.
The projects have been announced as part of the Hypersonics Challenge issued last year by LIFT – a public-private partnership between the US Department of Defense, industry and academia – which seeks to enable the US to manufacture hypersonic vehicles faster and more cost-effectively.
The first project, which Boeing is conducting in collaboration with Powdermet Inc, seeks to demonstrate near-net-shape manufacturing of metal matrix composite components for hypersonic vehicle demonstrators.
According to LIFT, the high-performance, high-temperature alloys will dramatically boost the capability of components in hypersonic flight environments, which when combined with near-net-shape manufacturing approaches will provide quality mission critical components that are durable, reliable, and rapidly manufacturable.
The second project, which Boeing is conducting in collaboration with partners RPM Innovations Inc and Intelligent Optical Systems Inc, aims to develop and verify a suite of in-situ process monitoring sensors and non-destructive evaluation approaches for laser-directed energy deposition (L-DED) applications. The sensors aim to remove the need for current post-process quality verification methods, which can be time-consuming and expensive. In-process monitoring on the other hand will help inform the quality of the build during the process, saving time and expensive metal powders.
‘These projects will benefit the entire American manufacturing base, helping spur technology development from material producers all the way up to original equipment manufacturers (OEMs),’ said Austin Mann, metallurgist/materials engineer at Boeing Research and Technology, and lead on the first project.
Taisia Lou, additive manufacturing senior engineer at Boeing, and lead on the second project, added: 'Cost-effective approaches to developing hypersonic components that are reliable and rapidly producible are critical to our national security, and these projects will lead us down that path.'
Researchers 3D-print fuel injectors for hypersonic testing
The new Boeing projects follow another announcement last month that researchers at Purdue University's Zucrow Laboratories are putting 3D-printed parts to the test in simulated hypersonic environments.
The researchers, led by Associate Professor Carson Slabaugh, are demonstrating that 3D printed fuel injectors made from high-temperature, high-strength superalloys are more robust than parts made using traditional methods such as casting.
Slabaugh and his team partnered with additive manufacturing firm VELO3D to print fuel injectors with complex geometries that achieve very high fuel-air mixing performance.
Additive manufacturing is being used to produce fuel injectors made from high-temperature, high-strength superalloys suited to extreme hypersonic conditions. (Image: Purdue University)
The researchers subtly varied the flow passages of the injector with five different designs, printed them out and ran them through a gauntlet of hypersonic-relevant test conditions.
'The VELO3D end-to-end manufacturing system produced dense parts requiring minimal post-processing,' said Strahan. 'With just a little bit of cleanup machining, we could install them into our research-scale combustor for testing. We could then measure the combustion efficiency produced by each geometry with the goal of generating a flow that is chemically and thermodynamically similar to the atmosphere at very high flight speeds.'
In just two weeks the team was able to isolate the highest performer that had all the stationary and dynamic features they were looking for.
With an injector design having successfully passed rigorous testing, the researchers now aim to assemble a large array of them into an even more powerful combustor, aiming for full-scale hypersonic testing in Autumn 2022.
