TECHNOLOGY/BUSINESS OPPORTUNITY LASER POWDER BED FUSION ADDITIVE MANUFACTURING PROCESS MONITORING AND OPTIMIZATION USING THERMIONIC EMISSION DETECTION

Opportunity: Lawrence Livermore National Laboratory (LLNL), operated by the Lawrence Livermore National Security (LLNS), LLC under contract no. DE-AC52-07NA27344 (Contract 44) with the U.S. Department of Energy (DOE), is offering the opportunity to enter into a collaborative partnership to further develop and commercialize LLNL’s novel laser power bed fusion additive manufacturing process monitoring and optimization technology based on thermionic emission detection.Background: Additive manufacturing (AM) stands to benefit significantly from increased application of process monitoring approaches due to the stochastic nature of defects produced during AM processes, and because the primary applications of AM are in industries with stringent materials requirements. Moreover, since the vast majority of AM processes are layer-by-layer, in situ monitoring provides a unique view into the interior of a built part during construction which is subsequently difficult to access once the part is

completed. Process monitoring data collected voxel-by-voxel during a build can provide a so-called ‘digital thread’ for increased confidence in final parts that is fundamentally part of today’s Industry 4.0 paradigm. Improved monitoring solutions along with more predictive models and optimal laser sources have helped to push metal AM, from a mostly prototyping technology to full scale part production. However, fundamental challenges still limit widespread industrial adoption of AM, particularly in performance critical applications, where qualification of AM-produced parts remains a significant obstacle.Description:  This methodology adds an in-process monitoring capability to a laser powder bed fusion platform. The components specific to this monitoring capability are:Current measurement device (i.e. NF Corporation,  CA5350 low-noise current preamplifier).Analog to digital convertor and recording device such as a field programmable gate array device (i.e. NI USB-7855 FPGA).Control computer for system control and analysis.The invention adds a current measurement device such as a NF Corporation, CA5350 low-noise current preamplifier and electrical connections to a conventional laser powder bed fusion additive manufacturing system (Figure 1). The powder bed is electrically isolated from ground and the powder bed is electrical connected to the current pre-amplifier. The laser is scanned across the sample and signals from the current measurement device are recorded via an analog to digital device such as an FPGA. Once the current is digitized there are multiple avenues of how the current data can be interpreted: process monitoring, setup automation and on-the-fly control.Advantages:Current detection equipment is relatively inexpensive compared to other methodologies.The signal can be measured with high bandwidth (sampling rates up to 1 MHz).Signals can be measured during processing over all build length scales.The results can be interpreted using established processing routines.The signal can be coupled to processing electronics for on-the-fly control and automation.Results are reducible to fundamental physical phenomena.Potential Applications:The invention is a method for simple, fast monitoring of the additive manufacturing process. It also has potential to provide signals at rates that allow for on-the-fly process control.Development Status:LLNL researchers performed validation experiments which showed that the recorded current changes when a stainless-steel plate is irradiated by the processing laser. The signal has been correlated to various processing conditions and potential sources of defects.LLNL has filed for patent protection for this invention.LLNL is seeking industry partners with a demonstrated ability to bring such inventions to the market. Moving critical technology beyond the Laboratory to the commercial world helps our licensees gain a competitive edge in the marketplace. All licensing activities are conducted under policies relating to the strict nondisclosure of company proprietary information.  Please visit the IPO website at https://ipo.llnl.gov/resources for more information on working with LLNL and the industrial partnering and technology transfer process.Note:  THIS IS NOT A PROCUREMENT.  Companies interested in commercializing LLNL's Thermionic Emission Detection During Laser Powder Bed Fusion for Additive Manufacturing technology should provide a written statement of interest, which includes the following:1.   Company Name and address.2.   The name, address, and telephone number of a point of contact.A description of corporate expertise and facilities relevant to commercializing this technology.3. A description of corporate expertise and facilities relevant to commercializing this technology.Written responses should be directed to:Lawrence Livermore National LaboratoryInnovation and Partnerships OfficeP.O. Box 808, L-795Livermore, CA  94551-0808Attention:  FBO 448-20Please provide your written statement within thirty (30) days from the date this announcement is published to ensure consideration of your interest in LLNL's Thermionic Emission Detection During Laser Powder Bed Fusion for Additive Manufacturing technology.