Department of Engineering Technology

The Department of Engineering Technology is one of the youngest departments at the Faculty of Mechanical Engineering. The department was founded in the year 2000 when the Department of Plastics and Metal Processing and the Department of Engineering Metallurgy merged. However, research, development and education in this subject area have been carried out since the year 1955. In that year the Department of Engineering Technology at the Technical University of Liberec was founded under the guidance of Professor Frantisek Kristka. In the last fifty years or so there have been several reorganizations of the department. Today the department is divided into two sections:

Metals and Plastics Forming Section, and Engineering Metallurgy SectionNowadays the Department focuses on supplying the needs of industry, in the fields of education, research into and development of metal forming, in particular the technologies of sheet forming, plastics processing, as well as casting and welding.In addition to its role in educating technically-minded students, the department is well known as an important partner of companies in industry. The department has been training people from industry for many years, not only those from the Liberec region, but from throughout the whole of the Czech Republic.

Research Focus The department specialises in applying research to solve problems in industry. The particular emphasis is on research into the influence of thermal and mechanical processes on the properties of the parts produced by different technological processes within the branches of metal forming, plastics processing, casting, and welding.As far as the technologies of plastics processing is concerned, the research is focused on analysing and optimising the processes of polymer processing, its mixtures and composites, in relation to thermal processes, as well as the rheology of plastic melts and the application of software simulations. This research is applied to increasing the usable properties and quality of the parts, optimising the construction of the moulds, the morphology of the plastic materials and also the non-conventional methods of injection, cooling, etc.In the area of metal forming and tribology, the department focuses developing new processes of production for sheet processing using numerical simulation and control of forming operations and tribological conditions in tools, with the emphasis on improving of

stamping´s surface quality.Research into the branch of casting is focused on analysing the porousness and crystal structure of the casts, dilatation properties during the casting with metal moulds and on analysing and optimising the metallurgical processes in the production of thin-walled casts.In the area of welding, research is being carried out in several fields: observation of welding process parameters, the influence on effective production and quality of fillet welds for MAG welding method, and the optimisation of welding conditions for materials which are quite difficult to weld – e.g. ferrous aluminides. Another area of interest is quality provision for resistance point welding by monitoring the electrical values of the welding process.

Services and Expertise Available • Solving projects from industry via a bachelor’s or master’s thesis

or by the team of department employees depending upon the level of complexity of the project itself.

• Computer aided construction and technological processes of sheet forming, plastic processing such as injection moulding, thermoforming and blowing, casting and welding metallurgical processes (MoldFlow, CadMould, SysWeld, PamForm, ProCast, etc.).

• Evaluationofmetalformability,examinationofsheetprocessingaccording forming limit values (FLD diagrams).

• Tribologicaltests;evaluationoflubricants,surfacesandsubstrates.• Evaluationofadhesivesusedforthemanufactureofcar-bodies.• Evaluationofphysical,mechanical, temperatureandrheological

properties of plastic materials and composites materials with a polymer matrix.

• Evaluation of the morphology of polymeric parts by thermalanalyses and studying their structure in polarized light.

• Experimental measuring during production – shrinkage of polymeric injected parts, temperature and tension analyses of processes and moulds, etc.

• Designandconstructionofequipmentandmoulds.• Analysisoftemperaturebehaviourofmouldsandsolidifyingcasts,

evaluation of tensions in the casts.• Measuring the dilatation of casting alloies during solidifying

and cooling.• Measuringthegascontentsofsandandcoremixtures.• Analysisofweldjointquality,weldingandsolderingprocesses.• Analysisofthesourcesofweldjointdefects,optimizingwelding

parameters, welding process stability. • Castironwelding,renovationofworn-outcomponentsbymeans

of surface treatments.

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• Branchof plasticwelding (strength calculationof tanks, design of the shape).

• Metallurgicalevaluationofcastsandweldments.• Evaluationofmicro-andmacro-structureofstampingsbypicture

analyses.• Solving technologicalproblemsduring theproductionprocess,

with the focus on the grade and quality of the parts.• Consultationandadvisorysupportinsolvingspecificproblemsin

industry.• Training of industrial specialists – courses, workshops and

schooling. • Critical analysis and expert help in the evaluation of projects,

tenders, etc.

Laboratories, Equipment, Certificates Laboratory of Plastic Materials TestingThe laboratory is equipped with modern equipment for testing the physical and mechanical properties of polymer materials. It also evaluates the material structure of plastics according to international standards on standard and non-standard testing parts, semi-finished and finished products. The laboratory is equipped with a light microscope with a digital camera and with a rotary microtome Leica, an extrusion capillary microscope plastometer, an impact hammer for toughness tests according to Charpy and Izod, a Ceast notch machine with a micrometer for normalized notches preparation, a Hounsfield tensile strength testing machine with testing heads of 500 N and 10 kN for evaluating the tensile, bending, press and sliding properties of plastic materials, a Shore scleroscope with testing heads A and D, and density and analytical scales. The laboratory also houses an ultrasonic welding machine for welding plastic materials and a drying cupboard with a tool for measuring the linear dilatation of polymer materials.

Laboratory of Plastic Pressing This worksite is equipped with an Engel Victory 80/25, non-column injection machine with a microprocessor control, and a water temperature control unit, part of which is equipment for temperature field monitoring inside as well as on the surface of the injection mould. It also monitors the temperature on the surface of the injected parts.The workplace is also equipped with a machine for vacuum thermoforming of thermoplastic sheets and a blow moulding machine made by the company GDK. This equipment is for extrusion-blowing of hollow bodies and it can evaluate the influence of the technological parameters on the quality of the hollow bodies which are produced. Here, it is also possible to produce plastic test pieces with different

moulds for analysing the plastic materials properties according to international standards.

Metal Forming LaboratoryThis laboratory is equipped with devices for testing material formability: a TiraTest 2300 material testing machine with a thermal chamber and a measuring head ranging from 10 kN, to 100 kN and 500 kN. It also has equipment for measuring material plasticity according Erichsen and a TZP device for deep-drawability. Therearealsohardnesstesters(Vickers,Brinell,Rockwells)alightmicroscope, a cabinet drier with air circulation, a machine for electrolytic etching and Abbe´s comparator.

Tribological LaboratoryThis workplace has unique equipment which enables staff to carry out tribological tests with the possibility of setting the sheet speed up to 400 mm/s, and set the value of contact pressure between material and tool up to 80 MPa, with a maximum force of 20 kN and the jaws temperature up to 98 °C. The design of this equipment makes it possible to simulate drawing conditions in the area of the drawing edge of the die and in the area of the blank-holder.

Press Shop This workplace is equipped with a pneumatic hammer, a hydraulic press, a crank and eccentric press, a lever and plate shear for the preparation and fabrication of samples for experimental analysis of manufacturing processes and product quality.

CAD/CAM Laboratory The purpose of this laboratory is to support the use of numerical simulations in a number of areas. These include: the development of products tool optimization, the technological process of sheet forming, injection of plastics, blow moulding of hollow plastic bodies, thermoforming of plastic and composite parts, as well as welding and casting technologies.

Casting LaboratoryThis laboratory has equipment for screen analysis and compacting the sand mixtures, measuring their strength, air permeability and gas content. There are also equipment for measuring the dilatation, electric resistance oven and drying oven for sand and core-sand mixtures.

FoundryThe shop is equipped with an electric inductive middle-frequency oven, a resistance batch furnace, equipment for measuring oxygen activity, the temperature fields of casts and the dilatation of casting alloy during solidification and cooling. Single-part prototype production of smaller casts is possible in the shop.

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Metallographic Laboratory The purpose of this workshop is to evaluate metal structure and their alloys. It is equipped with a metallographic grinding and polishing machine, a Haneman machine for measuring micro hardness and a Neophot 21 optical microscope with digital camera and SW analyses NIS-Elements.

Welding Laboratory The equipment in this laboratory can record and analyse welding parameters for arc welding. The laboratory is equipped with welding suppliesforMAGandWIGwelding–BDH550andNavigator3000AC/DC.

Welding ShopThe Welding Shop is equipped with welding machines for hand arcweldingmethods,aWBLP40machineforresistancewelding,an automatic machine for submerged-melt welding, a tool for gas cutting and for gas welding and deposition.

Important R&D results Supported by Research Programmes:• The optimisation of technological processes in metal sheet

forming, plastic processing and engineering metallurgy in relation to productivity and quality of production.

• Research into temperature and thermal processes in plasticsinjection moulding technology.

• The influence of technological conditions on shrinkage andshape deformation of the thermoplastic injected parts.

• Researchintotemperatureprocessesofthemouldsforcastingduring solidification the casts.

• Researchintotheinfluenceofthermalandmechanicalprocesseson the final properties of weld joints, and the evaluation of weld joint parameters for new construction materials.

Supported by the Czech Science Foundation: • The influence of metal sheet surface morphology on the

deformation progress during drawing of metal sheet stampings.

• Researchintothedeformationprogressandlimitstagesofthinsheets under high strain-rates.

• Researchintoaluminiumalloycrystallizationunderpressure.• Analyses of the boundary temperature and deformation

influences on aluminium alloy.

Supported from other public and non-public sources:• Thedevelopmentofamethodologyforevaluationofadhesive

joints and strengthening composite foils with respect to specific requirements of the automotive industry.

• The development of a methodology for the evaluation oftribological metal sheet properties during the drawing process.

Important Industrial Applications The development of a new blow-moulding machine with a servo motor and research into the influence of this construction on the technological process.

External Cooperation • Czech Research Society for Sheet Metal Working, Czech Republic• Czech Society for New Materials and Technologies, Czech

Republic• CzechFoundrymen’sSociety,CzechRepublic• AcademyofSciencesoftheCzechRepublic,CzechRepublic• PolskaAkademiaNauk,Poland• WeldingPraha,s.r.o.,CzechRepublic• ŠkodaAutoa.s.,MladáBoleslav,CzechRepublic• MagnaExteriors&Interiors(Bohemia)s.r.o.,CzechRepublic• Czech Technical University in Prague, Czech Republic; Brno

University of Technology, Czech Republic; VŠB – TechnicalUniversityofOstrava,CzechRepublic;TomasBataUniversityinZlin,CzechRepublic;UniversityofWestBohemia,CzechRepublic;CharlesUniversity inPrague,CzechRepublic;SlovakUniversityof Technology in Bratislava, Slovakia; Technical University ofKosice,Slovakia;ChemnitzUniversityofTechnology,Germany;UniversityofTokyo,Japan;UniversityofFranche-Comté,France;Otto-von-Guericke University Magdeburg, Germany; SilesianUniversity ofTechnology, Poland;The Katowice Branch of thePolishAcademyofSciences,Poland;UniversityofBielsko-Biela,UniversityofBielsko-BielaUniversityofBielsko-Biela,Poland;andothers.

References ŠkodaAutoa.s.,MladáBoleslav,CzechRepublic;MagnaExteriors& Interiors (Bohemia) s.r.o., Liberec, Libáň, Czech Republic;MecasEsi,s.r.o.,Plzeň,CzechRepublic;ValeoAutoklimatiozacek.s.,CzechRepublic;PLASTKOVMRa.s.,Liberec,CzechRepublic;FaureciaInteriorSystemsBohemias.r.o.,Plazy,CzechRepublic;Witte Nejdek spol. s r.o., Nejdek, Czech Republic; PfinderKG, Böblingen, Germany; FUCHS PETROLUB AG, Mannheim,Germany;Zeller+GmelinGmbH&Co.KG,Esslingen,Germany;ŽĎASa.s.,ŽdárnadSázavou,CzechRepublic;Ferex–ŽSOspol.sr.o.,Liberec,CzechRepublic;ModelárnaLIAZspol.sr.o.,Liberec,Czech Republic; Ernst Bröer, s.r.o., Hrádek nad Nisou, CzechRepublic;andothers.

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