William Makhetha

Cape Peninsula University of Technology, South Africa

Title: A Framework for Qualifying Surface Roughness in Additive Manufacturing for Aerospace Applications: A Guide for New Businesses

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Biography

Makhetha holds formal qualifications in Industrial Engineering from Stellenbosch University andMaterials Engineering from the University of Cape Town. With over 9 years of experience, he possesses the expertise to navigate the structure-process-property relationship in materials. His research focuses on sustainable manufacturing and technology commercialisation. Currently, he serves as the

Programme Coordinator for the Product and Industrial Design Programme at the Cape Peninsula University of Technology, leading a team of 14 staff. Dr Makhetha actively seeks to build collaborations with academia, industry, and governments to equip the next generation of innovators and leaders in Science, Engineering, and Technology.

Abstract

Despite the advantages of additive manufacturing (AM), including the production of complex geometries without traditional tooling, the inherent surface roughness in laser powder bed fusion (LPBF) components remains a challenge, particularly in aerospace applications where dynamic properties and fatigue resistance are essential. The roughness arises from factors like surface open pores, partially melted powder, and the staircase effect. These defects contribute to increased fatigue crack initiation and poor performance. This paper presents a process framework to assist new businesses in qualifying surface roughness for aerospace applications. By integrating literature insights with experimental data on Ti-6Al-4V produced under optimized L-PBF conditions, the framework offers a pathway to meet aerospace surface quality standards. Stylus-based profilometry revealed as-built roughness of 5 – 40?m, exceeding aerospace requirements, but post-processing using the Dry Electrolyte polishing technique reduced roughness to below the 3.2 ?m aerospace threshold. The proposed framework effectively guides the adoption of appropriate post-processing techniques, enabling compliance with stringent industrial standards and supporting the broader integration of AM technologies across industries.