Rapid manufacturing of rhenium components using EB‐PVD

Abstract

Rapid manufacturing of rhenium components using EB-PVD Vittal V. Prabhu Indraneel V. Fuke Sohyung Cho Jogender Singh Article information:To cite this document: Vittal V.If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -The purpose of this paper is to provide insights for understanding the relationship between rapid manufacturing process for rhenium components in jet nozzle fabrication using electron beam-physical vapor deposition (EB-PVD). Specifically, to develop a methodology to characterize and improve this new process through motion planning for maintaining uniformity in the deposition thickness. Design/methodology/approach -This research first identifies several important objectives for the process, and then develops an optimized heuristic method based on a look-ahead approach to generate motion plans for uniform thickness objective. In this heuristic, the surface of the workpiece is modeled using finite element method and the accumulated thickness of each layer on each element is computed based on its location in the vapor plume using a ray casting algorithm. Findings -Computational experiments show that the proposed algorithm can potentially provide significant improvements in the uniformity of the layers and cost savings in manufacturing compared to prevailing practice, especially for low-volume production such as aerospace applications.Research limitations/implications -In this research, net-shaped jet nozzle has been fabricated using a graphite mandrel. Therefore, the mandrelbased approach can be limited to producing hollow components. Practical implications -The proposed method is very generic and thus can be applied for multi-material manufacturing process identifying the sweet spot of the intersecting vapor plumes. Originality/value -This research can help the EB-PVD process for rapid manufacturing which has been considered as financially expensive to be accepted in real practice by providing a relationship of the process-to-product transformation through the developed motion planning methods.

The flexibility of industrial additive manufacturing systems

“…These could be wholly new products, be customizations of existing designs (Craeghs et al 2010), or have different physical or mechanical properties (Kumar and Choudhury 2002;Wong et al 2007). Akin to process flexibility, Prabhu et al (2005) link process parameter variation with flexibility as it can control the way parts are produced.…”

“…Rosen (2004, p. 43) identified that “[Additive Manufacturing] systems will be very flexible in that they will be capable of fabricating a wide variety of parts, and, potentially, products or modules.” These could be wholly new products, be customizations of existing designs (Craeghs et al , 2010), or have different physical or mechanical properties (Kumar and Choudhury, 2002; Wong et al , 2007). Akin to process flexibility, Prabhu et al (2005) link process parameter variation with flexibility as it can control the way parts are produced.…”

Optimization on selective laser sintering of metallic powder via design of experiments method

“…The product quality produced by the SLS is always affected by the process parameters like the laser power, the maximum energy deposited by the laser, the laser scan speed, the stepping distance, the powder characteristic and the size of the laser spot, etc. The effects of the SLS variables on the physical and mechanical properties of specimens have been studied by researchers (Prabhu et al, 2005;Kruth et al, 2004;Lee et al, 2005;Evans et al, 2005;Sreenathbabu et al, 2005;Yao and Tseng, 2002). In this study, the pulse frequency and the pulse duration of the laser beams, times of strikes of a pulse applying to a single laser spot and the particle size of the powder base material are the four selected controlled factors with two levels for each factor.…”

“…Most of the applications of RP primarily focus on verifications of models for fits and form inspection; on the other hand, rapid tooling (RT) concentrates on producing parts that can serve as long-term consistent tools (Prabhu et al, 2005). Hence, RT parts call for a higher standard in mechanical properties than those produced by RP processes.…”

Motion planning for coating process optimisation in electron beam physical vapour deposition

“…[5][6][7] Furthermore, making such capital intensive equipment more flexible to produce a larger variety of parts with shorter processing times would be advantageous because of reduced lead times and inventory costs. 8 Therefore, improved process planning and control is required to transform this highly variable process from an empirical art to a well controlled one giving consistent results.…”