Study finds 3D printing of metal parts could reduce an airplane’s weight by 4-7%; fuel, CO2 and metal savings
Using additive manufacturing (3D printing) to produce aircraft’s metal parts could save a significant amount of fuel, materials and other resources, according to a new study by researchers from Northwestern University, Argonne and Oak Ridge National Laboratories, and the US Department of Energy (DOE) Advanced Manufacturing Office. Among the findings of the study:
Estimated fleet-wide life-cycle primary energy savings at most reach 70-173 million GJ/year in 2050, with cumulative savings of 1.2–2.8 billion GJ.
Associated cumulative emission reduction potentials of CO2e is 93–217 million tons.
Thousands tones of Al, Ti and Ni alloys could be saved per year in 2050.
Led by Eric Masanet, the Morris E. Fine Junior Professor in Materials and Manufacturing at Northwestern’s McCormick School of Engineering, the team used aircraft industry data to complete a case study of the life-cycle environmental effects of using 3-D printing for select metal aircraft parts, a technique that is already being adopted by the industry. The team concluded that 3-D printing the lighter and higher performance parts could significantly reduce both manufacturing waste and the weight of the airplane, thus saving fuel and money and decreasing carbon emissions.
Funded by the US Department of Energy’s Advanced Manufacturing Office, the case study is described in a paper published in the May issue of the Journal of Cleaner Production. Runze Huang, a graduate student in Masanet’s lab, is first author of the paper. Other authors include Matthew Riddle and Diane Graziano from Argonne National Laboratory.
The airline industry is an early adopter of 3-D printing. The main driver is that aircrafts require specialized lightweight metal alloys that can be very costly to process.—Eric Masanet
Conventional manufacturing methods tend to be inefficient and wasteful. To produce a 1-kilogram bracket for an airplane, for example, it may require 10 kilograms of raw material input into the manufacturing process. And, from an engineering design perspective, that final bracket may still contain much more metal than is required for the job. 3-D printing, on the other hand, requires far less raw material inputs and can further produce parts that minimize weight through better design.
We have suboptimal designs because we’re limited by conventional manufacturing. When you can make something in layer-by-layer fashion, those constraints diminish.—Eric Masanet
Masanet does not anticipate a change to the crucial parts of the aircraft, such as the wings and engine, any time soon. However, he does see real potential in the replacement of less flight-critical parts, such as brackets, hinges, seat buckles, and furnishings. According to the case study, 3-D printing a bracket, for example, reduced its weight from 1.09 kilograms to 0.38 kilograms. This might not seem like much, but it adds up.
There are enough parts that, when replaced, could reduce the weight of the aircraft by 4 to 7 percent. And it could be even more as we move forward. This will save a lot of resources and a lot of fuel.—Eric Masanet
If the 3-D components evaluated in the case study are used to their full potential, Masanet predicted it would greatly benefit the environment in more than one way. First, his team estimated that airplane fuel consumption could be reduced by as much as 6.4 percent, reducing both fossil fuel dependency and greenhouse gas emissions. Second, their life-cycle analysis found that manufacturing 3-D printed components uses as little as one-third to one-half of the energy currently used in conventional methods. Manufacturers would also potentially save thousands of tons of aluminum, titanium, and nickel that are otherwise scrapped every year.
But Masanet said there is one caveat. Scientists need to improve 3-D printing technology to realize the full extent of the estimated aircraft weight savings. Limitations in the process, such as issues with surface quality, residual stresses, repeatability, and throughput, are current barriers to full-scale adoption. But Masanet hopes this case study will provide further proof that continued research efforts and funding should be focused on improving the 3-D printing process.
Runze Huang, Matthew Riddle, Diane Graziano, Joshua Warren, Sujit Das, Sachin Nimbalkar, Joe Cresko, Eric Masanet (2015) “Energy and emissions saving potential of additive manufacturing: the case of lightweight aircraft components,” Journal of Cleaner Production doi: 10.1016/j.jclepro.2015.04.109.