MASTER STUDENT PROJECT(30HP) Harmonic Structured materials: proof of fabrication concept from local supply Modern demands in new applications can be hardly met by the traditional approach of fabricating polycrystalline materials with homogeneous structures. Such materials are either ductile but too soft when coarse-grained (CG; crystallite size d£10µm) or strong but too brittle when ultrafine-grained (UFG; crystallite size d£1µm), see a schematic below. Since both strength and ductility are important characteristics for the majority of structural applications, fabrication of materials with superior combinations of both is as hot as ever issue in material engineering.

A recently emerging approach mitigating this problem is the fabrication of heterogeneous structures

architectured at multiple scales. Of particular interest in such approach is the formation of bimodal grain size distributions having ‘harmonic’ structure (HS) arrangement, see a schematic above. HS features islands of soft CG embedded into a continuous 3D skeleton of their strong UFG counterparts. We have been fabricating HS materials using powder metallurgy approach at Ritsumeikan University in Japan, and investigating their performance along with developing Finite Element models for the optimisation of design in Lund.

The master theses project on offer capitalises on these achievements. We team up with the wold-biggest manufacturer of metallic powders Höganäs AB to explore the potential of HS materials fabrication in Sweden from local supplies. The work is suitable for 1-2 students from the following programs: mechanical engineering, engineering physics or engineering nano science. Start 2016.

Supervisor: Prof. Dmytro ORLOV (Dmytro.Orlov@material.lth.se),

Department of Mechanical Engineering, LTH; Dr. Hilmar VIDARSSON (Hilmar.Vidarsson@hoganas.com),

Global Market & Product Development, Höganäs AB

Elongation

Strength

Ultrafinegrained

Coarsegrained

bimodal

bimodalHarmonic