PhD Position in Production and materials engineering, robotics, transport and logistics, Early...

Tallinn University of Technology, School of Engineering, Department of Mechanical and Industrial Engineering offers a 4-year PhD position in the field of production and materials engineering, robotics, transport and logistics.

Proposed doctoral thesis topic: "Selective laser sintering of bio-inspired composite structures".

Supervisor: Professor Irina Hussainova

Abstract

The PhD position is opened for an Early State Researcher to be involved into additive manufacturing through selective laser sintering of metal-matrix composite materials, which are in-situ reinforced by ceramic phase. The principal of bio-mimicry will be applied to the designed structures to ensure their high wear resistance.

Description

The project aims at far beyond the state-of-the-art platform for production of the bioinspired complex structured composites. The objective is development of light-weight highly wear resistant structures successfully working in tribo-conditions exploiting bio-replication of architecture and gradients of bone (energy absorption) and surface texturing of snake (low friction and wear). The ultimate goal of the project is twofold: (i) development of materials solutions allowing gradient manufacturing and in-situ reinforcement during AM through Selective Laser Melting/Sintering (SLM\S); and (ii) development of a technological procedure for modulating the local composition and structure for sintering lightweight reliable wear resistant composites. For SLM, the interaction between the laser beam and powder material is one of the dominant phenomena defining the feasibility and quality of process. To meet the demands, new adopted materials should be developed with the shape and size tolerances and compositions modified to fit the process.

The use of computational thermodynamics can guide in the tailoring of the phases comprising their interfaces and spatial distributions. However, defining the optimum material distribution function requires extensive knowledge of material data that includes the chemical composition, its characteristics and manufacturing constraints. Among the Al-based alloys, the most studied is AlSi10Mg. Very few alloys consisting transitional elements to stipulate on in-situ hardening through formation of intermetallic phases are detailed. Study on AM of an innovative Al-Mg alloy modified with Sc and Zr (Scalmalloy) is at very beginning, but results are promising. Some alloys being under protection are not studied yet. Moreover, AM of ceramic and ceramic-metal composites are far from mature.

Responsibilities and (foreseen) tasks

• To perform research on metal-matrix composites to be processed by SLM/S
• To develop/design (with the help of thermodynamic calculations) the materials suitable for SLS
• To model/design (using CAD) the topology/architectures of the samples to be tested
• To develop strategy for the fabrication of bio-mimetic structures
• To collect data and conduct case studies on the selected cases on experimental approaches and institutional innovations
• To characterize the materials (microstructure, composition, mechanical properties)
• To contribute to the organization of research and workshops where project findings are presented