Paanduv Applications’ Post

In the laser powder bed fusion (LPBF) additive manufacturing process, defects such as porosity can significantly deteriorate the mechanical properties of the products, especially pores that form due to the keyhole instability in the molten pool. Numerical simulation, specifically CFD of the LPBF process, is an efficient method for reducing costs and understanding the formation mechanisms of keyhole pores. The laser beam releases heat flux onto the metal surface, elevating its temperature. Once the solidus temperature is surpassed, the metal undergoes a phase transformation, initiating melting and forming a molten pool and keyhole. To enhance the simulation accuracy, UDFs have been written in C++ to account for energy and momentum sources, as well as phase transformations. Our research clearly demonstrates keyhole formation and molten metal flow results, using a coupled DEM-CFD process. #LIGGGHTS #Porosity #Additivemanufacturing #ANSYS #Fluent #CFD #LPBF #Simulationandmodeling

Laser Powder Bed Fusion - a process for everything? We are sometimes asked why we have eight (!) different AM processes for metals at Fraunhofer IFAM, if PBF-LB is available everywhere. The reason is simple, lasers can't do everything. It starts with the fact that the laser process is essentially welding and materials that are difficult to weld or prone to hot cracking, such as Al6061, the cutting steel M2, the nickel-based superalloy CM247LC or WCCo, are difficult or even impossible with LPBF. Furthermore, each process has its own sweet spot in terms of part size and productivity, to name just two parameters. This is illustrated below for the processes at Fraunhofer IFAM. For these reasons, we have the widest range of AM processes for metal worldwide to offer our customers the best AM process for their application. You want to use metal AM, but you don't know which technology is the right one? Come to us, we know! Want to know more about our possibilities? Visit us at Formnext - Where ideas take shape, Hall 11.0 booth D31 IF AM, then Fraunhofer IFAM #AdditiveScreenPrinting #3DScreenPrinting #MetalBinderJetting #GelCasting #MoldJet #FusedFilamentFabrication #ElectronBeamMelting #LaserPowderBedFusion #LMM

10 layers of Laser Powder Bed Fusion (LPBF process in additive manufacturing) simulation for a Titanium alloy using AM PravaH. Notice the layer-wise manufacturing of a thin metal wall as a completely transient simulation with solid phase, molten phase, vapor phase, and shielding gas phases are tracked. Additionally, all the phase changes, Gaussian laser distribution with Fresnel reflections, Marangoni convection, and Discrete Element Method (DEM) for exact power bed preparation (28-48 micron sized alloy powder particles) are computationally calculated. This simulation is run on a single 16-core processor and took under a day to run with the implementation of preventive timestep controls! #ampravah #additivemanufacturing #simulation #manufacturing #engineering

Keyhole Formation during LPBF Process LPBF includes intricate interactions between laser energy, powder material, and the resultant melt pool. These interactions take place at high temperatures and include phenomena such as vaporization and fluid movement, which are difficult to monitor. CFD simulations serve as a virtual window, allowing us to see and examine these processes in greater detail. The keyhole is essential for a good LPBF. A well-behaved keyhole promotes optimum melt pool geometry and smooth material deposition. CFD models can forecast keyhole parameters like as depth, size, and stability. This information is critical for adjusting laser power, scan rates, and other LPBF process parameters to obtain the desired keyhole profile. Uncontrolled keyhole dynamics can cause flaws such as porosity (air pockets) and spatter (ejected molten material). The application of AM PravaH, a customized CFD program for additive manufacturing simulations, is demonstrated in the movie. AM PravaH is a potent tool for AM process optimization as it probably includes features and models designed especially to simulate the intricate physics of LPBF. " #additivemanufacturing #3dprinting #lpbf #keyhole #meltpool #simulation

Keyhole formation during the LPBF process. LPBF includes intricate interactions between laser energy, powder material, and the resultant melt pool. These interactions take place at high temperatures and include phenomena such as vaporization and fluid movement, which are difficult to monitor. CFD simulations serve as a virtual window, allowing us to see and examine these processes in greater detail. The keyhole is essential for a good LPBF. A well-behaved keyhole promotes optimum melt pool geometry and smooth material deposition. CFD models can forecast keyhole parameters like as depth, size, and stability. This information is critical for adjusting laser power, scan rates, and other LPBF process parameters to obtain the desired keyhole profile. Uncontrolled keyhole dynamics can cause flaws such as porosity (air pockets) and spatter (ejected molten material). The application of AM PravaH, a customized CFD program for additive manufacturing simulations, is demonstrated in the movie. AM PravaH is a potent tool for AM process optimization as it probably includes features and models designed especially to simulate the intricate physics of LPBF. #additivemanufacturing #lpbf #meltpool #simulation #AMPravaH

As most of you might know, we offer a variety of preheating systems, like resistive heatings up to 500°C or even inductive preheating up to 1200°C! 🔥 However, we know it can be challenging to maintain the right temperature in the process plane when heating from the bottom. For very advanced applications and materials, it’s crucial to achieve the right temperature exactly where the laser interacts with the material. 💥 That’s why we’ve teamed up with IPG Laser GmbH & CO. KG to solve this for LPBF! 💪 Now, we can preheat precisely where the laser is interacting with the powder. The system allows preheating temperatures above 1000°C in just seconds ⏱️! Our current studies will test processing of tungsten and hard-to-weld nickel-based superalloys, but we’re open to exploring more materials! Do you have an application or material in mind that needs a high and consistent temperature in the process plane? Let us know! 👇 #PreheatingSystems #3DPrinting #AdditiveManufacturing #LaserProcessing #IPGPhotonics #HighTemperature #LPBF #AdvancedMaterials #ManufacturingInnovation #Engineering #3DTech #Tungsten #NickelAlloys #MetalAdditiveManufacturing #AC3D #Aconity3D

Curling and delamination between layers along the build direction can introduce tiny cracks at the edges of an additively manufactured specimen. In this case, a crack growth simulation is performed in Ansys Mechanical by initiating multiple cracks at the edges of a gyroid model created within Ansys. It is fascinating to observe the SMART (Separating, Morphing, and Adaptive Remeshing Technology) dependent fracturing and remeshing of multiple cracks simultaneously as the specimen is progressively bent (top view). The entire model is shown in the bottom view. The simulation demonstrates the capability to perform mixed-mode fracturing of complex TPMS structures, extending the study beyond the mode-I fracturing investigated in my previous work. - https://lnkd.in/eBp9RNke #fracture #fatigue #simulation #FEA #Additivemanufacturing #3dprinting #crackgrowth #TPMS #Ansys Structures

🧲 Solid fraction refers to the process that shows the transformation of molten metal from a liquid state to a solid state during the solidification process of the casting. Once a particular area of the molten metal has completely solidified, that region becomes transparent and no longer visible, thus the image consistently displays the liquid phase area. Each isolated liquid zone can be a source of shrinkage porosity and needs to be paid attention to. 👇 Click to discover the future of die-casting simulation with SupreCAST: https://lnkd.in/ep2xTNX2 #casting #diecasting #simulation #castingsimulation #simulationsoftware #CAE #suprecast

Fairly happy with a Crack Growth Simulation of Gyroid structure in Ansys 🙂! To relate to the past projects and support ongoing projects concerning fracture behaviour of Additively Manufactured TPMS structures, both ABAQUS and Ansys have been tested. In that particular instance Ansys mechanical offers a robust and streamlined workflow allowing an exemplar Gyroid model created in nTop imported into ANSYS for the desired crack growth simulations. The attached video demonstrates the snapshot of SMART crack growth simulation in which it is mesmerising to observe the smart remeshing at the crack front as the crack tip is opening (top view). The whole model is shown at the (bottom view). #fracture #fatigue #simulation #FEA #Additivemanufacturing #3dprinting #crackgrowth