New Developments in Laser Cladding for Industrial Manufacturing Processes
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- Clemence Holt
- 5 years ago
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1 for Industrial Manufacturing Processes Tim Biermann, Fraunhofer ILT with contributions from: Dr. A. Gasser, Dr. K. Wissenbach, Dr. I. Kelbassa, Dr. A. Weisheit, Dr. N. Pirch, G. Backes, St. Linnenbrink, T. Jambor, S. Ocylok
2 Contents Introduction New Hardware - Benefit by new laser sources - Cladding devices & optics New Processes - Micro cladding - Graded layers - Cladding onto light metal alloys Examples Conclusion and outlook
3 Contents Introduction New Hardware - Benefit by new laser sources - Cladding devices & optics New Processes - Micro cladding - Graded layers - Cladding onto light metal alloys Examples Conclusion and outlook
4 Laser cladding with powder feeding Laser Powder nozzle Powder / gas Bonding zone Layer High diversity of additive materials High accessibility Repairing of sensitive surfaces Melt Base material HAZ Layers of 0,05 mm thickness up to several cm No undercut and low heat input
5 Laser cladding expertise Handling / powder feeding components Process management Materials 100 µm Laser sources Process modelling Process monitoring
6 Contents Introduction New Hardware - Benefit by new laser sources - Cladding devices & optics New Processes - Micro cladding - Graded layers - Cladding onto light metal alloys Examples Conclusion and outlook
7 Laser sources and overall absorptivity for cladding 100 % Nd:YAG laser (1064 nm) Laser power: 460 W Overall absorptivity η 2,5 3,5 % 35 % 25 % η % 84 % 70 % 60 % CO 2 -laser (10,6 µm) Laser power: 1300 W CO 2 -Laser Nd:YAG / Diode Fibre / Disk - Laser
8 Concepts for powder feeding nozzles coaxial off-axis continuous discrete
9 Concepts for powder feeding nozzles off-axis coaxial-continuous coaxial-discrete good accessibility direction dependant 5 mm 5 mm 5 mm small powder focus (less than 100 µm possible) robust and suited for 3D-cladding
10 Cladding head for inside processing (Nd:YAG- or diode laser) custom-build on demand Processing diameters: Shown model > 50 mm Down to 25 mm possible powder
11 Cladding head for endoscopic inside processing (diode laser) IBO Module III: Fibre connector support IBO Module IV: Support for guide tube IBO Module II: Optic IBO Module I: Head Guide Tube Fibre connector (Light fibre) Optic and protection glass Outer diameter: 22 mm Length: 102 mm 2 internal cooling cycles, powder supply, shielding gas supply In cooperation with Rolls-Royce Deutschland
12 Zoom optic for stepless variable track width Solid state and diode lasers CNC controlled Laser power up to 3 kw Variable tracks widths approx. 0,6 mm 4 mm Constant tool centre point 3D-cladding possible Up to 90 degrees inclination possible 50 mm In cooperation with Reis Lasertec
13 Industrial standardisation of nozzles Example of discrete coaxial nozzle for CO 2 -laser Discrete coaxial nozzle Continuous coaxial nozzle In cooperation with TRUMPF
14 Contents Introduction New Hardware - Benefit by new laser sources - Cladding devices & optics New Processes - Micro cladding - Graded layers - Cladding onto light metal alloys Examples Conclusion and outlook
15 Comparison of experimental and computational result Front view Cross section Longitudinal section High speed photography / lateral view
16 Melt pool geometry, temperature, heating and cooling rates Temperature field / T [K] Heating/cooling rate / CR [K/s]
17 Features of micro cladding Laser source: fiber laser with a focus diameter d 50 µm Powder: Particle size < 20 µm State-of-the-art dimensions of layers: Width 50 µm Thickness 10 µm Stellite layer (d = 24 µm) on stainless steel plate
18 Applications for micro cladding: Medical Science Electronic Industry Energy Sector SEM Electronic switch Silver contact Gold contacts Cross section 1 mm 50 µm Fa. Angiomed X-ray 200 µm 2 mm Increasing X-ray visibility by cladding markers made of tantalum on nitinol stents Fa. Inovan GmbH 4 mm Selective cladding of silver contacts on stainless steel switches Reduction of used precious material Gold contacts for fuel cells FZ JülichJ
19 Graded layers experimental setup diode laser (λ 1 =808nm, λ 2 =940nm) - laser power P L =1,4kW - fokus diameter d Fokus =2mm 5-axis handling twin powder feeder type of nozzle: coaxial discrete powder feeder with two chambers (change of powder composition while process is running) Component A Component B 100% 0% 80% 20% 60% 40% 40% 60% 20% 80% 0% 100%
20 Graded layers made of Metco 42 C and CPM 420 V Linear increase of hardness throughout graded layers punctual decrease of hardness caused by heat affected zones hardness > 750 HV 0,3 possible Härte [HV 0,3] CPM 420 V Härteabfall Decrease of durch hardness WEZ caused by HAZ Gradient Versuch 20 Probe 5 Substrat Metco 42 C V20 P5 CPM 420 V Hardness increases P L =749W d Strahl =2,0mm V Vorschub =600mm/min 0 0,0 0,4 0,8 1,2 1,6 2,0 2,4 2,8 3,2 3,6 4,0 4,4 4,8 5,2 5,6 6,0 6,4 6,8 7,2 7,6 8,0 8,4 Distance from surface Abstand von der Oberfläche Metco 42 C
21 Cross-section, AlSi20 onto Mg alloy (AZ91D-sandcasted) AlSi20 cladding Mixing zone AZ91D-substrate (sandcasted) Mg 2 Si - seam
22 EDX analysis, AlSi20 onto Mg alloy (AZ91D-sandcasted) cladding: Al-rich Mg 2 Si - seam substrate: Mg-rich Mg 2 Si Mg 2 Si Mg 2 Si
23 Wear and corrosion, AlSi20 vs. Mg alloy (AZ91D-sandcast) Corrosion-resistance of AlSi20 extremly better compared to Mg alloy Wear rate of AlSi20 cladding compared to AZ91D substrate reduced by approx. 70% (Pin-on-disc test, counterpart: Al 2 O 3 -ball, without lubrication) 0,0016 Abrasionsrate [mm³/nm] 0,0012 0,0008 0,0004 0, approx. - 70% 0, After 196h salt spray test 0,0000 AZ91D, sandcasted AZ91D-Druckguss Material Werkstoff AlSi20, lasercladded AlSi20
24 Contents Introduction New Hardware - Benefit by new laser sources - Cladding devices & optics New Processes - Micro cladding - Graded layers - Cladding onto light metal alloys Examples Conclusion and outlook
25 Applications in aero engines / BR Turbine Front drum (Titanium) In cooperation with Rolls-Royce Deutschland
26 Reconditioning of damping wire grooves / Ti6246 Front drum Laser cladded groove Before / after cladding Main challenges: Accessibility Processing without affecting opposite wall
27 Repair of HPT Case at several locations / Inconel 300 mm
28 Machine implemented at Rolls-Royce, Oberursel 1 kw lamp pumped Nd:YAG laser axis (turning table) Automated powder mass flow measurement Automated laser power and beam profile measurement (PRIMES)
29 Laser cladding of gear components at Stork Gears & Services, Rotterdam Applications Petrochemical industry / offshore drilling Shipping Storage and transhipment Sugar industry Steel industry Energy companies Source: Stork Gears & Services
30 2 kw fibre coupled diode laser from Laserline Discrete coaxial nozzle Turning table Robot system Typical layer thickness 0,5 mm Hardness HRC Repair of gear components at Stork Gears & Services Replacement of: Chromium plating Thermal spraying In cooperation with Stork Gears & Services
31 Repair of gear wheel for handling crane Source: Stork Gears & Services
32 Thermal spray coating replaced by laser cladded layer Thermal spray coating Laser cladded Source: Stork Gears & Services
33 Repair of gearboxes Source: Stork Gears & Services
34 Repair of axis of cable winch of tow boat Husky Source: Stork Gears & Services
35 Repair of planetary gear Bearing surfaces refurbished with Nickel alloy on nodular cast iron Source: Stork Gears & Services
36 Conclusion and outlook Laser cladding has become an established technique for the repair and the wear protection of high added value components of machines The higher wall-plug efficiency and absorptivity of new laser systems compared to CO 2 -lasers has led to a higher competitiveness of laser cladding New components (zoom optic for variable track width, standardized powder nozzles, inside processing heads) New developments like graded materials and micro cladding are opening new applications Increase of modelling capabilities Acknowledgment: Roll-Royce Deutschland TRUMPF Laser und Systemtechnik Reis Lasertec Stork Gears & Services
37 Upcoming Event Thank you for your attention! See you again May 5 7, 2010 in Aachen You are invited to our 25th anniversary!