ROBOTIC WIRE ARC ADDITIVE MANUFACTURING OF METAL PRODUCTS

Transcription

1 Fakulteta za strojništvo Laboratorij za varjenje ROBOTIC WIRE ARC ADDITIVE MANUFACTURING OF METAL PRODUCTS Damjan Klobčar 1, Janez Tušek 1, Maja Lindič 1, Boris Bell 2 1, University of Ljubljana, Aškerčeva 6, 1000 Ljubljana, Slovenia; damjan.klobcar@fs.uni-lj.si 2 School center Postojna, Cesta v Staro vas 2, 6230 Postojna, Slovenia COST CRM-EXTREME, , Prague, Czech Republic

2 INTRODUCTION

3 AM technologies

4 Comparison of different AM technologies

5 Advantages and disadvantages of AM technologies Powder-bed Blown-powder WAAM Part size 10 Build rate 10 Complexity 10 Hi. Dep. Wire-fed Platform flexibility Accuracy 10 Post-processing requirement 10 Cost savings 10 Mech. properties 10 Material utilisation

6 History of WAAM 1926 Baker patent of electric arc as heat source for deposition of melted material to manufacture 3D object 1971 Ujiie (Mitsubishi) manufacturing of pressure valve with SAW, ESW and TIG welding multi wire and multi materials Kussmaul shape welding of large and high quality nuclear construction parts from 20MnMoNi5 steel (build rate 80 kg/h, mass 79 ton) Prinz, Weiss patent of hybrid CNC machine for welding and milling Shape Deposition Manufacturing Cranfield University development of Shape Metal Deposition process for manufacturing of castings for aircraft engines for Rolls Royce. H2020 FoF OPENHYBRID from CAD to production with advanced all-in-one machines

7 Materials and products Usually used material for Additive Manufacturing Titanium alloys Aluminum alloys Tool steel Other alloys Stainless steel Temperature resistant Ti-6Al-4V Al-Si-Mg H13 IN & 316L MoRe ELI Ti 6061 IN Ta-W CP Ti 347 CoCr γ-tial PH 17-4 Dissimilar part Steel/bronze (CuSi3%) 1 metre tall turbine blade (steel) 2.5 metre x 1.2 metre aluminium wing rib for Bombardier Projectiles 0.8 metre tall aluminium/steel conics built for Lockheed Martin

8 Samples from our laboratory

9 Materials Steel, Titanium, Aluminium Buy to Fly = efficiency of fedstock material Aircraft landing gear = Vfeedstock/ Vproduct Aircraft wing structure Steel Titanium Mass [kg] BTF Cost [k ] Cost red. Original, machined Original, WAAM % Original, machined Original, WAAM % Design options (MRR =[323 kg/h]) BTF Cost [k ] Machined from solid Cost red. WAAM, option % WAAM, option %

10 EXPERIMENTAL PART Determination of parameters for stable WAAM process thin walls Welding power source: Fronius TransPuls Synergic 3200 CMT R Welding robot: ABB IRB 140-6/0.8 Temperature measurement: VOLTCRAFT M 3850 Base metal: S335 dimension: 100x25x8 mm Filler wire: G3Si1 (VAC 60) Shielding gas: CO2, CORGON 18, Ar Gas flow: 10 l/min Parametric analysis (I = 40, 90, 140 A, w speed = 3, 7.5, 12 mm/s) standard, CMT and pulse welding control, Welding in positions: PA, PC and PG Analysis (tensile test, hardness measurement, metallographic analysis). Manufacturing of final part (CAD + SprutCAM path programing). D. Klobčar, 3D tiskanje kovinskih. DVT in DNVT 2016, IZV, Ljubljana, Slovenija,

11 RESULTS Optimization of welding parameters STANDARD PULS CMT

12 Voltage - U [V] Process optimization University of Ljubljana Eliminate the slope with alternately changing welding direction and control of interpass temperature Slope - Welding to one side Alternating direction (I=90 A, v=7,5 mm/s) Eliminate wavy surface with optimization of heat input Welding current - I [A] 1. Optimisaiton 2. Optimisation CMT CMT+PULZ Wavy surface

13 Layer height [mm] Layer width [mm] University of Ljubljana Optimization of process parameters - CMT+PULS I=59 A, v=5 mm/s, Q=103,8 kj/m I=90 A, v=7,5 mm/s, Q=244,8 kj/m I=141 A, v=7,5 mm/s, Q=419,2 kj/m I = A A (cold (hladno welding) varjen) 3 5 I = A A (average ( povp. navarjene interpass stene - medvarkovna temperature tem. 200 C) 200 C) 2, , , Welding speed [mm/s] Welding speed [mm/s]

14 Successful welding in different welding positions University of Ljubljana PA a) I = 40 A, v = 5 mm/s a) b) c) b) I = 90 A, v = 7,5 mm/s c) I = 140 A, v = 7,5 mm/s Higher energy input -> wider and higher weld deposit. PC I = 40 A, v = 5 mm/s Lower energy input -> preventing of excessive melting. PG I = 90 A, v = 7,5 mm/s Lower energy input -> holding the melt at end of weld.

15 Angle [ ] Force [kn] Force [kn] University of Ljubljana 1,2 1 a) b) c) Force [kn] 0,8 0,6 0,4 0, Elongation [mm] 1,2 1 0,8 0,6 0,4 0, ,4 1,2 1 0,8 0,6 0,4 0,2 0 Elongation [mm] Elongation [mm] Tensile strength of deposit is lower than the filler metal 45 Angle 90 Angle 0 Angle The filler metal: Rm = MPa

16 WAAM of tube welded at I = 59 A, v = 5 mm/s

17 How to affect the use of CRM Potential use of the technology - To produce the tools with increased lifetime. - Multimaterial components

18 Project proposal The use of additive manufacturing to increase the lifetime of industrial tooling

19 CONCLUSIONS A parametric analysis of WAAM using MIG/MAG welding for production of thin wall structures was done. An optimally low heat input during weld deposition ( kj/m) must be done in order to make stable deposition of layer dimensions. At < 100 kj/m wavy weld deposition; at > 300 kj/m melting of material. It is important to control the weld interpass temperature. It should not exceed 100 C. An optimal process to control was achieved by combination of CMT and pulsed welding. Welding in different welding position is possible; the easiest welding is done in PA position. When welding in other positions we must consider the gravity, weld interpass temperature, and energy input.

20 THANK YOU FOR ATTENTION We are open for collaboration Acknowledgment The work was partly sponsored by EU European Regional Development Fund and Ministry of Education, Science and Sport of the Republic of Slovenia under the Strategy of Smart Specialisation Project MARTINA (MAteRials and TehnologIes for New Aplications) The work was partly sponsored by EU European Social Found, Ministry of Education, Science and Sport of the Republic of Slovenia and Slovene human resources development and scholarship fund under the project name Robotic weld surfacing.

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