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Laser Additive Manufacturing for Remanufacturing of Critical …€¦ · Additive manufacturing...
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Laser Additive Manufacturing for Remanufacturing of Critical Components Bingbing Li, Assistant Professor California State University Northridge
Transcript of Laser Additive Manufacturing for Remanufacturing of Critical …€¦ · Additive manufacturing...
Laser Additive Manufacturing for Remanufacturing of Critical ComponentsBingbing Li, Assistant ProfessorCalifornia State University Northridge
Research Highlights
Sustainable design and manufacturing, sustainability analysis of nanotechnologies, life cycle assessment, and manufacturing energy efficiency
Additive manufacturing (Laser cladding for remanufacturing, selective laser sintering/melting, fused deposition modeling, inkjet bioprinting)
Advanced manufacturing process, CAD/CAM, CNC. Nanomaterials/structure for energy conversion and storage
(lithium ion battery)
National Basic Research Program (973 Program)“Fundamental Scientific Research on Remanufacturing of Mechanical Equipment”, Ministry of Science and Technology of China, ￥38.0 million ($6.3 million), 2012-2016.
Laser additive manufacturing for remanufacturing of critical components
•Additive•Subtractive•Deformation
How can we make physical form?
Presenter
Presentation Notes
Additive: 3d printing, laser deposition Subtracting: cutting, milling, turning Deformation: rolling, forging, extrusion 美 ['difɔr'meʃən]
National Additive Manufacturing Innovation Institute (NAMII)
The official announcement of the award came on August 16, 2012 at NCDMM’s Youngstown, Ohio facility and the headquarters of NAMII.
ASTM International Committee F42 on Additive Manufacturing Technologies defines additive manufacturing as the process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies.
Desired Shape
Actual Shape from AM
Definition of Additive Manufacturing
Presenter
Presentation Notes
ASTM: American Society for Testing Material 美 [ə'pozd] adj. 相反的；敌对的 美 [,ɪnə'veʃən] Semi sphere
Industries using RP
Additive Manufacturing Processes
1D scanning 1D Parallel 2D Area-Filling
Pattern Energy Vat PhotopolymPowder Bed FusionElectrochemicalDeposition
Mask-Projection VPSheet Lamination
Pattern Material Material Extrusion Material JettingBinder Jetting
Thermal Spray
Pattern both Material & Energy
Directed Energy Deposition
AM Process TypesASTM Standard Industry Names Vendors
Vat Photopolymerization Stereolithography 3D Systems, Envision TEC, FormLabs
Powder Bed Fusion Selective Laser SinteringLaser MeltingElectron Beam Melting
3D Systems, EOS, ARCAM, Renishaw
Material Extrusion Fused Deposition Modeling Stratasys, 3D Systems, Printrbot
Material Jetting MultiJet ModelingPolyJet
Stratasys, 3D Systems, Sanders
Binder Jetting 3D Printing 3D Systems, EX One, VoxelJet
Directed Energy Deposition Laser Engineered Net ShapingDirect Metal Deposition
Optomec, DM3D, Sciaky, Insstek
Sheet Lamination Laminated Object ManufacturingUltrasonic Consolidation
Mcor Technologies, CAM-LEM, Fabrisonic, Solido
Fundamental of Laser Cladding
Typical single layer thickness: 0.2-2.0 mm
Heat input in part: low-moderate
Dilution with substrate material: less than 5%
Adhesion: metallurgical boning Structure: completely dense Base materials: carbon steel,
alloyed steel, stainless, cast iron, nickel, alloys
Coating materials: Fe-, Co-, Ni-alloys, metal
Presenter
Presentation Notes
Metallurgical 英 [,mɛtə'lɝdʒɪkl] adj. 冶金的；冶金学的
Turnkey system of laser cladding equipment
Cladding System Components• Power source (Laser)• Power delivery (Optical
fiber)• Optics• Motion system• Powder feeder• Powder delivery nozzle
Laser
Optics
Nozzle
Motion system
Laser Model: YLS-2000 Laser type: optical fiberMaximum Power: 2000WWidth: 3nmNozzle: YC52
Remanufacturing is the process of disassembly and recovery at the module level and, eventually, at the component level. It requires the repair or replacement of worn out or obsolete components and modules.
A rough case analysis of a heavy duty diesel engine.
N e w R e m a n u f a c t u r e
C o s t R e d u c t i o n
E n e r g y S a v i n g
M a t e r i a l S a v i n g
E n v i r o n m e n t a l I m p a c t
ReduceSignificantly
Application: Remanufacturing
Rotor: 6.4 meter long, weighed 7 ton, value ￥120 million
Core Component of Typical High Value-added Mechanical Equipment
Cleaning
Abrading
Laser repair
Complete appliance
Denaturation
Fatigue
Surface interface
Cone Joint
BaringShaft Diameter Axis
BalancingDrum
ImpellerSeal
SealSleeve Locking
NutIm
pelle
r
Spa
cing
Pie
ce
Technical Challenge
Application: die cutter and blade in the rotary cutting die equipment
•PNV Machinery Co
Remanufacturing Process by Laser Cladding
Materials
Sample Powder Particle size (mesh) Density (g/cm3) Mobility (s/50g)1 Nickel base alloy #1 115 700 4.89 132 Iron base alloy #1 65-325 3.44 24.63 Iron base alloy #2 27-80 7.8 14
Table Properties of cladding powder
Sample Powder C B Cr Si Ni Mn Mo P O S Fe Cu1 Nickel base alloy #1 0.02 1 2 base 0.052 0.7 19.382 Iron base alloy #1 0.13 1.17 15.45 1.08 1.45 1.05 base3 Iron base alloy #2 0.2 1.2 15 1.05 2.0 0.75 1.3 base
Table Chemical composition of cladding powder
Substrate is steel C45, and cladding materials are Ni-base and Fe-base alloys
Presenter
Presentation Notes
表中的K1，K2，K3分别表示各水平各因素试验所得硬度的和。从具体的数值看，粉料2和3都是铁基成分，结合强度相差不大，而粉料1为镍基成分，抗剪切应力不到粉料2和3的一半，说明不同粉料对熔覆的结合强度影响很大。从不同激光功率的熔覆件的抗剪切应力来看，3KW为2500.6MPa，4KW为2711.4MPa，5KW为2742.1MPa，说明激光功率的增大，结合强度逐渐增大。而从扫描速度看，600mm/min最大，400mm/min次之，500mm/min最小，未发现明显的规律。 R为(range)极差，即各列中各水平对应的实验数值平均值中最大值与最小值之差。从表4中可以看出，粉料种类的极差最大，说明粉料对结合强度的影响最大；激光功率的极差最小，说明粉料对结合强度的影响最小。
Experiment Process•To minimize the number of experiments and prevent high cost of experiments, it is designed against a three level Taguchi’s Orthogonal Array that required 9 specimens in total to be carried out.• Step 1: Adjust the laser to ensure it operate normally and keep the focal length of 300mm.• Step 2: Remove the rust and oxide layer on the surface with abrasive paper to achieve a
certain roughness, and clean the oil contamination with acetone.• Step 3: The types of powder, laser power (3, 4, 5 kW), rotate speeds (6.3, 7.9, 9.5 r/min,
corresponding to the scanning speed 400, 500, 600mm/min) are selected for experiments, as shown in Table 3 L9 (33) Taguchi orthogonal array. The substrate C45 with length 100mm and diameter 20mm was clamped on the workstation. Experiment is implemented by a CO2 laser (model Han’s Laser 6000) with spot size of 3mm and automatic feeding. The layer is fused by laser cladding nozzle as a multiple-layer coatings with thickness rang of 2.5-3.2mm.
# Sample Laser power (kW) Speed (rpm)1 1 3 6.32 1 4 7.93 1 5 9.54 2 3 7.95 2 4 9.56 2 5 6.37 3 3 9.58 3 4 6.39 3 5 7.9
Presenter
Presentation Notes
表中的K1，K2，K3分别表示各水平各因素试验所得硬度的和。从具体的数值看，粉料2和3都是铁基成分，结合强度相差不大，而粉料1为镍基成分，抗剪切应力不到粉料2和3的一半，说明不同粉料对熔覆的结合强度影响很大。从不同激光功率的熔覆件的抗剪切应力来看，3KW为2500.6MPa，4KW为2711.4MPa，5KW为2742.1MPa，说明激光功率的增大，结合强度逐渐增大。而从扫描速度看，600mm/min最大，400mm/min次之，500mm/min最小，未发现明显的规律。 R为(range)极差，即各列中各水平对应的实验数值平均值中最大值与最小值之差。从表4中可以看出，粉料种类的极差最大，说明粉料对结合强度的影响最大；激光功率的极差最小，说明粉料对结合强度的影响最小。
Experiment Process
• Step 4: After laser cladding, both lateral surfaces of the clad layer of each substrate are cross sectioned to height 2mm for metallographic analyses. Then the round bar is cut into small pieces with total length 20mm by wire electrical discharging machine.
Schematic illustration of Experiment (h=2mm, ∅=20mm, clad layerthickness=2mm) The Actual Shearing Experiment
Experiment Process
Fracture behavior of the 9 specimens after shear strength test. Distribution points of hardness test
Experiment
# Sample Laser power (kW) Speed (rpm) Shear stress (MPa)1 1 3 6.3 423.62 1 4 7.9 468.43 1 5 9.5 592.54 2 3 7.9 964.25 2 4 9.5 1161.26 2 5 6.3 1203.27 3 3 9.5 1112.88 3 4 6.3 1081.89 3 5 7.9 946.4
Table Strength of orthogonal experimental design
Powder Laser power Scan rate
Strength
K1 1484.5 2500.6 2708.6K2 3328.6 2711.4 2379K3 3141 2742.1 2866.5R 614.7 80.5 162.5
Table Shear Strength
Presenter
Presentation Notes
表中的K1，K2，K3分别表示各水平各因素试验所得硬度的和。从具体的数值看，粉料2和3都是铁基成分，结合强度相差不大，而粉料1为镍基成分，抗剪切应力不到粉料2和3的一半，说明不同粉料对熔覆的结合强度影响很大。从不同激光功率的熔覆件的抗剪切应力来看，3KW为2500.6MPa，4KW为2711.4MPa，5KW为2742.1MPa，说明激光功率的增大，结合强度逐渐增大。而从扫描速度看，600mm/min最大，400mm/min次之，500mm/min最小，未发现明显的规律。 R为(range)极差，即各列中各水平对应的实验数值平均值中最大值与最小值之差。从表4中可以看出，粉料种类的极差最大，说明粉料对结合强度的影响最大；激光功率的极差最小，说明粉料对结合强度的影响最小。
Results
(a) whole image (b) bond part of cladding layer and substrate c) cladding layerSEM of cladding layer of sample #4
-6 -5 -4 -3 -2 -1 0 1
100
200
300
400
500
600
700
Micr
o-ha
rdne
ss/H
V
Distance to surface/mm
1#6#
0 1 2 3 4 5 60
100
200
300
400
500
600
700
Micr
o-ha
rdne
ss /H
V
Distance of laser spot center/mm
1# 6#
Presenter
Presentation Notes
interface 图4是取结合强度最低的1号件和结合强度最高的6号件熔覆层横截面上不同区域的显微硬度测试结果，图4（a）以结合面为起始点（0点），自上而下不同距距离打点，熔覆层之上距离为正值，之下为负值，同一层面上打2个点取平均值；图4（b）为距离工作表面0.2mm，以光斑中心为起始点（0点），自左向右每间隔1mm打1点，同一垂直面打2个点取平均值，硬度分布为图3所示。从图4（a）可以看出不同熔覆层显微硬度都比基体高，特别是在熔覆接合部在基体一侧显微硬度明显比熔覆层和基体高。光斑直径是3mm，一半是1.5mm，从图4（b）可以看出在距离光斑中心2mm后，显微硬度接近基体的硬度，说明激光能量集中，对熔覆区侧面影响较小。 图5（a）是4号试样放大50倍的熔覆层整体形貌，从图5（b）和图5（c）分别是4号试样放大200倍的熔覆层结合部和中部图。从图5（b）可以看出有一条时常狭窄的白亮带。从结合部向熔覆层方向，可以看到结晶形态由平面晶(plane lattice)向胞状晶（cellular lattice crystall）和树枝晶(tree lattice)发展。主要原因是高能激光束使粉末熔化、凝固并与基体产生冶金反应，属于快热快冷动态过程。根据快速凝固理论，开始时基材表面温度低，温度梯度较大，结晶速度小，成分过冷接近零，非均匀形核主要依附基材表面形成一层平面晶。随着凝固过程的进行，液-固界面的推进，结晶区前沿溶质变化程度也逐渐加强，温度梯度逐渐变小，结晶速度变大，成分过冷增加，从而平面晶向胞状晶和树枝晶发展[15]。从图5（c）可以看出组织均匀致密，与基体成良好冶金结合，无微观裂纹。
Conclusion
The powder type has the largest dependency, followed by scanning speed. The laser output power has minimal impact.
The bonding strength with iron-based powder is much higher than that with the nickel-based powder. The bond strength increases as the laser power increases.
No obvious dependence of bonding strength on scanning speed has been found.
The micro hardness of both clad layer and bonding surface is higher than that of the substrate. Side effected zone is small in this research.
