Technology Description
Direct Energy Deposition (DED) is most unique Metal AM process as it uses a deposition nozzle mounted on a multi-axis machining system, which can create highly complex metal parts that can be produced faster and with increased flexibility. The schematic representation of LAM-DED System is as given:
DED is also the only process which allows Multi Material 3D Printing for manufacturing parts with Functionally Graded Materials for enhanced functional performance of the parts.
Other advantages of DED process are:
- High Build Rates – DED’s higher deposition rates at relatively low resolution means a faster build rate than other metal additive manufacturing processes.
- Dense and strong parts – DED creates higher-density parts hence their mechanical properties are as good as cast or wrought material.
- Near Net Shape – Parts can be near net shapes requiring minimal post-processing.
- Can be Used for Repairing – Ideally suited for application requiring metal addition to existing parts hence lends itself for repairing applications.
- Multi-material Range – Latest DED machines have the capability to have several different powders or wire containers which enables to build parts with custom alloy.
- Larger parts – Comparably larger parts can be built using DED. For example, Insstek DED printers have the capability to print parts a few meters long.
- Easy Material Change – Since the material is fed during the process on demand from separate powder containers, it’s easy to refill or change the material.
- Reduced Material Waste – DED only deposits the material it needs during the process meaning less wastage compared to processes like powder bed fusion (SLS and DMLS), where the full build platform has to be filled with metal powder
Applications
DED is already utilised in key industries like aerospace, defence, oil & gas, and the marine industry, for example, aircraft frames and structures, refractory metal components, ballistic material tooling repair and reconditioning and, marine propulsion, etc.
MRO
MRO stands for Maintenance, Repair and Operations — or sometimes Maintenance, Repair and Overhaul — and refers to the equipment, tools and activities associated with the daily operations of a business. It doesn’t include materials, products and services that are directly used in production, but rather the glue that holds everything together. MRO may include HVAC (Heating, ventilation, and air conditioning)maintenance, facility lighting, janitorial services, CNC (Computer Numerical Control) machinery, drill presses, forklifts, jacks, PPE, powered and manual hand tools, mops, brooms and even furniture. MRO can be routine, planned maintenance activities, also called preventive MRO; it can be predictive, when data indicates machinery is deteriorating and needs maintenance; or it can be corrective, after an incident occurs.
Examples of MRO and MRO Materials
As mentioned above, MRO includes almost everything related to a company’s day-to-day business. But what exactly does this entail? The following examples take a look at areas that are part of maintenance, repair, and operations and the materials needed:Facility ManagementThe facility be it a factory, an office, or a storage place – is vital for a company, which is why it is an important part of MRO. Everything related to the building needs to be maintained and serviced at regular intervals, meaning that all materials related to this process can be considered MRO materials.
Industrial Equipment
Maintenance, repair, and operations naturally include industrial equipment directly needed for a business to operate; either to manufacture a product or offer a service. MRO for industries typically involves all types of materials used for machines and equipment, such as motors, pumps, spare parts, etc.
Automobile
HeadLamp Mold Repair
It was originally required to manufacture a new mold for headlamp But remodeled the mold through hybrid printing with DED Technology. Customer could have operational effectiveness: Lead-time simplification Material cost reduction
Wheelset Bearing
The part, which weighs 13 kg, was printed in just 7 hours, providing Deutsche Bahn with benefits like increased part availability and considerably lower manufacturing costs. Ultimately, using 3D printing allowed the company to put the train back on track much faster and avoid lengthy and costly downtime.
Crankshaft Repair
Traditionally, to repair theses shafts, thermal spry processes have been employed, but thereafter, in some cases, some defects, such as severe spalling, have been revealed on some repaired shafts. Afterward, more deep investigations have shown that DED can provide better metallurgical and mechanical bonding concerning the thermal spray processes and can be considered as a more reliable solution to repair the drive shafts. Moreover, from the economic point of view, it is interestingly found that the cost repairing of drive shafts via DED is 50% of the production of a new drive shaft
Four Stroke Marine Piston Repair (KIMI)
During the working condition of Four Stroke Marine Piston, high level of forces and temperature damage the surface of pistons. Wear, which is the main defect, happens on the edges of the grooves under the working environment and, thus, the pistons should be repaired or replaced as soon as the grooves reach the tolerance limit. Kimicompany has repaired these pistons by DED process as an economical and technical solution that not only repairs the part but also improves the resistance of groves against the erosion and corrosion
Atomizer Shaft
- This 4340 Atomizer Shaft is a high speed (8800rpm) precision shaft used in “Flue Gas Desulfurization” (FGD) scrubber systems.
- Shafts were previously repaired by a Spray Process featuring a “Mechanical Bond.”
- Laser Repair utilizes a “Metallurgical Bond” that generates a high quality permanent repair
- Repair includes deposition of 420L SS to tapered fit section and seal surface
SS Atomizer Shaft
- Atomizer shaft operates at 13,000 RPM
- Seal area of shaft was worn and repaired with 420L SS
- Nut and threads were repaired using 316L SS
Bearing Surfaces
- Replaces tool steel parts with long lead time
- Cladding steel with CoCr material on wear surfaces only
- Improved part life on average by 2X-3X conventional part lifetime
ID Surface Repair
- Repair or add wear resistive materials to ID surfaces
- ID head capabable of depositing in 2.25″ (57mm) ID cylinders, up to 24″ (609 mm) deep
- Multiple orientations possible
Ti-6Al-4V Driver Plate
- Forging delivered undersized (no outer lip)
- Laser deposited the outer lip oversized and final machined to print
Gas turbine Inconel 718 compressor seal is a critical and high-value component that can be repaired using the DED process. The application of this seal in the gas turbine aims to prevent gas leakage in gas turbine engines. In this component, the main damage is the excessive wear in the labyrinth seal that negatively affects the performance of the gas turbine. Image shows a very finesse repair of a damaged gas turbine compressor seal.t the cost of a repaired compressor seal was 45% of a new one, and this confirmed the great potential of DED as a repair technology from the economic point of view.
Atomizer Shaft
Integral rotors of an aircraft engine, which are commonly known as bladed disks or “blisks”, are made of titanium alloys. In general, these blisks get locally damaged over their larger areas. It is reported that due to their aerodynamic profile that must be repaired precisely, the repair of these blisks faced several challenges.
Compressor Blade Aircraft
A repair and overhaul methodology to recover the complex geometry of expensive parts for aerospace industries. A repair process on a critical aero-engine component like thin-curved compressor blade. Their repair approach included the 3-D non-contact digitization, free-form surface reconstruction using DED process, and milling operations in an automatic hybrid process. It was found that the total repair time through their approach was 30% lower than the conventional methods. The proposed repair methodology could be taken into account as a reliable and time-cost effective approach in comparison with the conventional repair methods.
Other advantages of DED process are:
Die Defects
