Product Code: ICA11_505

Development of a Model for Prediction of Material Properties of Laser Cladded Inconel 718 As Related to Porosity in the Bulk Material
Authors:
Johannes Witzel, Chair for Laser Technology, RWTH Aachen University; Aachen Germany
Thomas Schopphoven, Fraunhofer Institute for Laser Technology; Aachen Germany
Andrés Gasser, Fraunhofer Institute for Laser Technology; Aachen Germany
Ingomar Kelbassa, Chair for Laser Technology, RWTH Aachen University, Fraunhofer Institute for Laser Technology; Aachen
Presented at ICALEO 2011


High value jet engine components such as compressor blades or BLade Integrated DiSKS (BLISKS) are manufactured by time and cost-prohibitive conventional techniques, such as five-axis milling, linear friction welding and electro chemical machining. This project within the Fraunhofer Cluster of Innovation TurPro qualifies the Laser metal deposition process (LMD) as a new green manufacturing method for nickel and titanium alloy-based BLISKs. Thus, a significant increase of the deposition rate (factor 10 or higher) is of interest. Aiming for a process certification of additive manufacturing of BLISK blades, using conventional manufactured disks as a substrate, quality assurance and predictable material properties remain a major concern. In this paper, the distribution of pore sizes of laser deposited Inconel 718 (IN 718) is investigated using deposition rates of up to 7000 mm3/min. Using quantitative image analysis, defining sub-sets and applying extreme value and logarithmic Gaussian distribution, the pore-size-distribution in the bulk material can be described with solely 4 statistical parameters. Based on these parameters, the ultimate tensile strength (UTS) of a cladded sample can be estimated with an accuracy of approx. 250 - 300 MPa.