Title: Newly conceived aerospace fasteners produced by DMLS: mechanical characterization for design and process validation

Duration: 6 months

Where: Universidad Politècnica de Valencia – Departamento de Ingeniería Mecánica y de Materiales

Contact persons: professor David Busquets Mataix (Academic tutor, dbusquets@mcm.upv.es), Dr. Alessio Tommasi (company tutor, alessio.tommasi@gemmate-technologies.com)

The context

Gemmate Technologies participates in MAESTRO Horizon 2020 project investigating novel design concept to produce component for space applications. Such aerospace components designed and manufactured in MAESTRO project are evaluated by Gemmate Technologies through a technological and economical assessment in order to define their capabilities and limitations.

The component type chosen for the project is a Highly Stressed Fastener (hereinafter HSF for simplicity). Specific applications of HSF are used for connecting thin metal panels assembling the payload of a satellite. Since these components, all together, represent a significant part of the rocket shipping, also their weight shall be decreased and treated as an important voice of the overall economical balance of a launch. To this end the development of HSF significantly lighter in weight and still compliant with an assembling in microgravity conditions is proposed.

a)      Currently produced fasteners, b) optimised and lightweight space fasteners, c) first prototype produced by DMLS.

The project outcomes will endow Gemmate Technologies of the needed knowledge for IP protection, co-engineering service for component producers, development of advance proprietary design methods for launching new additive manufacturing products, and the acquisition of a pilot line.

Thesis objectives

The main goal of this thesis is to analyse the mechanical behaviour of the new conceived aerospace fasteners. Various mechanical properties identify the reaction of a fastener to applied loads. It is not often that the mechanical properties of a fastener are equal to those of the raw material the fastener was made of. The raw material establishes the base property for the fastener, while the final combination of mechanical properties of the fastener is obtained during the manufacturing and post-treatment process.

During the thesis several mechanical properties will be evaluated by means of different tests in compliance with international standards, namely: axial load test, shear test, self-locking torque, fatigue test, stress embrittlement test, and vibration test. Starting from existing standards new ones will be defined in order to regulate the testing of aerospace fasteners manufactured by additive manufacturing.

The student coached by both academic and company tutoring will carry out the test for component validation and will actively contribute to the publication production paving the bases for the construction of a personal records for a brilliant future career.


The technical and relational skills acquired during the proposed thesis could represent a solid base for future collaborations at Gemmate Technologies or among the project partners, in the framework of the presented project or in similar scientific context.