Rapid Qualification of Additive Manufacturing Processes with Mechanics and NDE Modeling

ABSTRACT: This work develops a simulation framework and demonstrates a methodology to integrate nondestructive evaluation (NDE) and stress analysis to cost effectively assess the ability to detect critical defects as determined by an assessment using a simulation environment of damage growth based on material properties, part shape and local stress fields. Integrating emerging simulation tools in NDE, stress analysis and damage evolution we demonstrate a powerful approach to lifing assessment using a damage tolerance approach, thus providing a key component in the emerging additive manufacturing processes. Integrating XRSIM (NDE simulation), DARWIN (damage evolution) and NESSUS (optimization tools), for the first time, demonstrates a means that accurately captures the relationship between critical AM design cycle parameters with defect morphology in NDE and damage evolution. Key for this integration is developing quantitative and part appropriate probability of detection curves needed for accurate lifing analysis yielding a significant cost reduction by reducing the need to rely on extensive experimental POD curves. A plan to address verification, validation and uncertainty quantification in the use of models and simulations for rapid qualification is provided. The Honeywell, Southwest Research Institute and NDE Technologies partnership in this project positions us to further dovetail with ongoing DARPA AM programs. BENEFIT: This project proposes to enable rapid qualification of AM processes through the development of a methodology that accurately captures the relationships between key manufacturing parameters and the resulting product, including location-specific microstructure, defects, material properties, inspectability, and damage tolerance. This methodology will, in the short term, integrate predictive models for non-destructive evaluation (NDE), stress analysis, and damage tolerance (DT) simulations, by leveraging our expertise and existing products XRSIM, NESSUS and DARWIN. In the longer term, the methodology will also broaden the integration to include simulations of the manufacturing process and microstructure-property relationships. Significant design cycle time savings are possible by identifying the best process parameters needed for an optimized design, allowing for a faster response time to engineering changes and requirements that will enable the full range of AM benefits. An additional benefit is for simulation methods to generate NDE POD curves. We are planning to demonstrate several methods, 1. Directly from XRSIm, 2. Using XRSIM to supply Monte Carlo simulation or response curves. These results combined with Nessus generate POD curves. Cost savings are huge in that a demonstrated means to generate meaningful POD curves if only from a reduction of the sample costs. Specific cost savings to additive manufacturing users will come from a reduction in the number of rejected parts. When a virtual inspection is performed, lots of virtual parts can be scrapped at first. As the process is adjusted the number of virtual part rejections reaches an acceptable level. If the model has been properly calibrated and V & V"d, this will lead to fewer scrapped parts. The cost reduction is directly proportional to the reduction in rejected parts. Two major components of the proposed integrated modeling environment, DARWIN and XRSIM, are already successful commercial products in certain markets. Their integration and further development here will result in significant expansion of their commercial potential, including for example, selling XRSIM to current DARWIN customers, and selling DARWIN to current XRSIM customers. Exposure to other, particularly non-aerospace, industries is expected as these industries begin to implement DMLS and other AM processes. Since these two software programs are both mature and supported by existing marketing and sales organizations, expansion into these new markets will be expedited.