A Numerical Study into the Effect of Machining on the Interaction between Surface Roughness and Surface Breaking Defects on the Durability of WAAM Ti-6Al-4V Parts
Daren Peng,
Rhys Jones,
Andrew S. M. Ang,
Victor Champagne,
Aaron Birt,
Alex Michelson
Affiliations
Daren Peng
ARC Industrial Transformation Training Centre on Surface Engineering for Advanced Materials, School of Engineering, Swinburne University of Technology, John Street, Hawthorn, VIC 3122, Australia
Rhys Jones
ARC Industrial Transformation Training Centre on Surface Engineering for Advanced Materials, School of Engineering, Swinburne University of Technology, John Street, Hawthorn, VIC 3122, Australia
Andrew S. M. Ang
ARC Industrial Transformation Training Centre on Surface Engineering for Advanced Materials, School of Engineering, Swinburne University of Technology, John Street, Hawthorn, VIC 3122, Australia
Victor Champagne
US Army Research Laboratory, U.S. Army Combat Capabilities Development Command Weapons and Materials Research Directorate, Aberdeen Proving Ground, Aberdeen, MD 21005, USA
Aaron Birt
US Army Research Laboratory, U.S. Army Combat Capabilities Development Command Weapons and Materials Research Directorate, Aberdeen Proving Ground, Aberdeen, MD 21005, USA
Alex Michelson
Solvus Global, 104 Prescott Street, Worcester, MA 01605, USA
The airworthiness certification of military aircraft requires a durability analysis be performed using linear elastic fracture mechanics (LEFM). Furthermore, such analyses need to use a valid small crack growth equation. This paper focuses on the effect of rough surfaces and the effect of machining the surface on the durability of AM parts using LEFM and a valid small crack growth equation for the material. To this end, this paper analyses the effect of surface roughness on wire and arc additively manufactured (WAAM) Ti-6Al-4V titanium parts and the effect of machining on the durability of a part. The analysis reveals that the life of the component is a relatively strong function of the degree of surface roughness, and that the durability of a specimen is a strong function of the local radius of the curvature of the trough. It also appears that surfaces with tall narrow roughness will not overly benefit from partial machining of the surface.
