Comparison between mechanical properties of specimens and tear down of representative airframe Ti-6Al-4V L-PBF part

Tuesday, May 8, 2018: 8:00 AM
Osceola 1-2 (Gaylord Palms Resort )
Mr. Marcos Miyazaki , Embraer, São José dos Campos, Brazil
Dr. Giorgia Aleixo , Embraer, São José dos Campos, Brazil
Mrs. Danielle Silva , Embraer, São José dos Campos, Brazil
Mr. Felipe Brandao , Embraer, São José dos Campos, Brazil
Mr. Marcio Cruz , Embraer, São José dos Campos, Brazil
Mr. Carlos Roberto de Haro , Embraer, São José dos Campos, Brazil
Prof. Eckart Uhlmann , Fraunhofer IPK, Berlin, Germany
Mr. Tiago Klein , Fraunhofer IPK, Berlin, Germany
Mr. Robert Kersting , Fraunhofer IPK, Berlin, Germany
Additive Manufacturing (AM) is a cutting edge technology with regard to aerospace application. This process offer the possibility to manufacture parts with complex geometries and mechanical properties similar to those manufactured by traditional subtractive manufacturing methods. But for AM parts, the application for structural components is still a challenge. Due to this, Embraer has been studying and developing AM technologies.

Laser Power Bed Fusion (L-PBF) is one of the AM processes having the highest potential for aeronautic application of metallic end-use parts.

This work presents the mechanical properties and microstructural evaluation of Ti-6Al-4V parts by L-PBF process. It gives a detailed view on design for AM, topology optimization, manufacturing and testing specimens, and also the tear-down of a representative demonstrator part.

Test specimens and demonstrators’ evaluation was performed by tensile and fatigue tests, as well as microstructural characterization. In addition, non-destructive CT-scan was carried out.

For both specimens and demonstrators, following manufacturing sequence was applied: 3D printing of the specimens/parts by L-PBF, stress relief heat treatment, HIP, and milling of specimens and tear-down.

Lamelar microstructure was identified in the “as L-PBF” condition, whilst columnar microstructure was pictured after the heat treatment in this α + β titanium alloy.

The specimens were manufactured in three different building orientations: 0°, 45° and 90°. Regarding tensile tests, specimens fabricated at 45° presented higher values of tensile strength in comparison to specimens manufactured horizontal or vertical. Furthermore, fatigue test results showed that specimens manufactured at 45° exhibited slightly higher fatigue strength when compared to specimens manufactured at 90° and 0°.

Regarding the tear-down of the demonstrator, the tensile and fatigue tests results presented equivalent values to the L-PBF specimens.

See more of: Additive Manufacturing III
See more of: Technical Program