The university of Notre Dame turbine machinery laboratory (NDTL), Norsk Titanium, Pratt & Whitney, and TURBOCAM international announced further testing of monolithic Titanium blade propellers made using additive manufacturing techniques. The first test was completed in 2018, which will test the propeller's dynamic performance. The product is manufactured using Norwegian titanium rapid plasma deposition TM (RPDTM) technology and will be certified in accordance with pratt & Whitney's current quality certification standards for turbine machinery components. This test proves that additive manufacturing can be applied to turbomechanics, and paves the way for complete product certification.
The testing will take place at NDTL's turbine-machinery testing center in indiana, USA, which has the most advanced technology in the world. After the first test, the product meets all design, speed and pressure ratio test points. This test focuses on the high cycle fatigue and low cycle fatigue characteristics of the product. The test will include a variety of acceleration and deceleration tests to observe the impact of real-time vibration on the blades.
TURBOCAM international performed a manufacturing quality evaluation before the test. No residual stress concentration was found in the assessment. Stress concentration leads to deformation. TURBOCAM international also determined that the materials used by the Norwegian titanium rapid plasma deposition TM technology are also suitable for traditional rolling mills, and can match the performance of ti-6al-4v forgings.
The final plan for the project was to establish specifications for making complex, overloaded parts for turbomachinery. At the same time, achieve the goal of reducing manufacturing cost and production time. This goal has been achieved in the manufacture of airframe parts for the Ti6Al4V.
Pratt & Whitney will oversee the entire manufacturing and testing process to provide data support for future engine development. A spokesman for the company said it was a pleasure to be part of the test. The use of additive manufacturing technologies, such as Norwegian titanium's rapid plasma deposition TM technology, allows for reduced manufacturing steps and development time for key turbine machinery components.
Norwegian titanium rapid plasma deposition (TM) technology is another metal 3D printing technology compared to our common powder bed based 3D printing technology for molten metal. According to ASTM classification, TM technology of rapid plasma deposition belongs to directional energy deposition (DED)3D printing technology. It is said that, through its own research and development of DED directional energy deposition technology (LENS coaxial powder feeding laser cladding 3D printing technology), pulitrix has many years of experience in 3D printing of the overall blade tray.
Additive components have been used for many years on aircraft, but their use has been limited to non-critical components such as plumbing and interior components. Even when used in engine parts (such as the famous GE Leap engine fuel nozzle), the performance requirements of the parts are mainly heat transfer rather than mechanical performance. As for the overall blade disc, the challenge comes from both heat conduction and mechanical performance. It can be said that if the 3D printed overall blade disc can pass the test of multiple layers of aviation performance requirements, it is indeed a milestone for additive manufacturing.
However, for aircraft applications, how to obtain certification is an important challenge. Because the aircraft industry tends to certify the design of parts and stick to it throughout the life of the aircraft. Pratt & Whitney's full participation plays a key role in promoting the certification of 3D printing.
In addition, in February 2019, SAE and Norwegian titanium introduced the standard for the application of directional energy deposition (DED) 3D printing technology. The two standards jointly formulated are AMS7004 (titanium alloy prefabricated parts for ti-6al-4v stress relief plasma arc oriented energy deposition additive manufacturing) and AMS7005 (wire feeding plasma arc oriented energy deposition additive manufacturing technology). The new standard sets the minimum requirements for aerospace customers to purchase Norwegian titanium rapid plasma deposition prefabricated parts. This laid a foundation for the development of Norwegian titanium in the aerospace field.
Norwegian titanium received the first FAA airworthiness certification for 3d-printed titanium alloy structures in February 2017. The technology has been applied to Boeing's 787 dreamliner. It claims to reduce the cost of parts by 30 per cent and reduce energy consumption, material waste and production cycles.