Investigating the material properties of 3D printed aerospace components

Abstract

Gas turbine blades play a vital role in attaining the maximum efficiency of the gas turbine. In a typical gas turbine engine, the gas temperature at the turbine section could be as high as 1500 ℃, with rotational speeds of up to 10,000 rpm. With such constant exposure to such harsh environments, the blades would be susceptible to creep failure, corrosion, and fatigue. To improve engine performance, a huge emphasis is placed on the blade design. As such, modern gas turbine blades design encompasses various internal and external cooling techniques and features for heat transfer enhancement. This paper provides a review of some of the cooling techniques such as rib turbualated cooling in serpentine channels, film cooling, jet impingement cooling, and pin fin arrays for blade trailing edge cooling. With such complexities in blade geometry, blade fabrication poses a challenge to manufacturers. Traditionally, blades were fabricated through investment casting. However, as the blade geometry gets more complex, investment casting would be a time consuming and costly process as additional moulds have to be created to cater for any design changes. 3D printing alleviates this issue by allowing the blade to be printed as a single part and provides a means for rapid prototyping. The design of blades for 3D printing process are explored, with variations of cooling features in the design. The paper presents two blade designs by the author and relevant features used for each design would be discussed in the blade design section.