Hello Stefania,
thanks a lot for your insight into your simuliation for the PBF process. On slide 4 you say, that physical properties should be known, whereas in your conclusion you say this simuliation is for new material developments as well. So your approach (Monte Carlo Simulation) helps to improve the simulation without physical properties in the first place or which physical properties are necessary?
Thanks a lot for your help to better understand.
Best regards,
Lukas
The objective of the work is to provide a tool to determine a feasibility region for LPBF processes. The input data for the model are: physical properties (density, heat capacity, thermal diffusivity) of the material and information about the variance-covariance matrix for MC simulation.
for this preliminary experiment we tested AISI 316L for which the physical properties are well-known and also information about the variability of the melt pool data can be derived from the literature. Surely, this procedure can be extended to new materials as long as the physical properties are known, usually if the material can be processed with LPBF was previously tested in laser welding or fundry technology so the physical properties of interest should be already known form ISO/ASTM standards or from the literature.
The MC simulation helps in considering the inevitable variability of the melt pool which is typical of LPBF processes because the molten material is not continuous but it is a powder feedstock, with particles with different size (and shape). So, the idea that for each combination of process parameters (speed and power) we obtain only one melt pool depth and width is not realistic. The MC simulation tries to include this aspect in the selection fo the process parameter window for LPBF. The input of the MC simulation are the melt pool depth and width which are the result of the thermal model.
Hello Stefania,
thanks a lot for your insight into your simuliation for the PBF process. On slide 4 you say, that physical properties should be known, whereas in your conclusion you say this simuliation is for new material developments as well. So your approach (Monte Carlo Simulation) helps to improve the simulation without physical properties in the first place or which physical properties are necessary?
Thanks a lot for your help to better understand.
Best regards,
Lukas
Hi,
thank you for your question.
The objective of the work is to provide a tool to determine a feasibility region for LPBF processes. The input data for the model are: physical properties (density, heat capacity, thermal diffusivity) of the material and information about the variance-covariance matrix for MC simulation.
for this preliminary experiment we tested AISI 316L for which the physical properties are well-known and also information about the variability of the melt pool data can be derived from the literature. Surely, this procedure can be extended to new materials as long as the physical properties are known, usually if the material can be processed with LPBF was previously tested in laser welding or fundry technology so the physical properties of interest should be already known form ISO/ASTM standards or from the literature.
The MC simulation helps in considering the inevitable variability of the melt pool which is typical of LPBF processes because the molten material is not continuous but it is a powder feedstock, with particles with different size (and shape). So, the idea that for each combination of process parameters (speed and power) we obtain only one melt pool depth and width is not realistic. The MC simulation tries to include this aspect in the selection fo the process parameter window for LPBF. The input of the MC simulation are the melt pool depth and width which are the result of the thermal model.
I hope this helps you,
Stefania
Hello Stefania,
thanks a lot for your detailed answer and explanation.
Lukas