Arçelik is a worldwide producer and marketer of consumer durables and consumer electronics with more than 22 manufacturing facilities with 30.000 employees.
Arçelik participates in FormPlanet project to validate the advanced testing methodologies for more accurate metals characterisation in sheet metal parts for the optimisation of forming processes and advance towards a defect-free part production.
In this case study the aim was to figure out the cause of the tearing and thickness reduction problem on the surface of a refrigerator compressor shell in deep drawing process.
Tests on three different steel materials, in sheet form and real part, were performed to investigate their mechanical behaviour and determine the one performing better. Standard and Miniaturised Tensile Tests (MTT) were carried out to evaluate the Yield Stress, Ultimate Tensile Stress, Elongation and Uniform Elongation in three different orientations. A metallographic analysis was also performed to obtain the microstructure and grain size distribution on core and surface areas.
Results were compared to those obtained by Arcelik and used to update the material specification and optimise the mould for the compressor part. Other tests were performed after controlling the tearing problems and thickness reduction with 3D scanning to validate the results and confirm the forming behaviour.
“The study helped us to know to select the best material for a specific product, improve the mechanical characteristics of the resulting part and optimise the mould to reduce thickness without tearing, cutting costs, time and reducing the amount of rejected material”.
Sehmuz Ali Subay, R&D Specialist, ARÇELIK
Micro-Tensile Tests (MTT) permit to locally assess basic tensile properties as yield stress, ultimate tensile strength, total elongation, reduction of area and uniform elongation. Furthermore, MTT can be used to study strain rate sensitivity in a wide range of temperatures.
These miniaturised testing techniques can be successfully applied when insufficient volume of material is available, for the development of new alloys, for the evaluation of the local mechanical properties of in-service components and as an input data in numerical simulation for advanced material modelling.