Aug 15, 2017

ADDITIVE MANUFACTURING BY COLD SPRAY TECHNOLOGY J. Karthikeyan and C.M. Kay ASB Industries Inc., Barberton, OH-44203, USA

Additive manufacturing has become the most sought after technique at present for producing and retrieving high tech parts and components. Cold spray process uses a supersonic particle jet to consolidate powder particles into high quality coatings and sprayed free forms. Cold-sprayed coatings are formed by solid state plastic deformation of sprayed particles and hence these coatings have compressive rather than tensile stresses, wrought-like microstructure, near theoretical density, oxides and other inclusions-free coatings. Moreover, cold spray process allows large throughput of powder, resulting in a high particle density beam and high deposition rate (DR). Also, cold spray process has a high deposition efficiency (DE), leading to very high material buildup. Using multiple powder hoppers or pre-blended powders, cold spray can produce multi-compositional and graded structures. Fundamental requirements of the Additive Manufacturing (AM) process are (i) high quality layers, (ii) fast (high DR) and flexible material processing, (iii) adaptability of the process for CAD/CAM Robotic processing and (iv) economical (high DE) processing of material.

Since cold spray process satisfies all these requirement, it has become one of the most sought after AM technique in both R&D and industry. Cold spray AM technique has been used in both production of ultrathick layers for repair/refurbishment of mis-machined and service-damaged parts as well as for the fabrication of features and near net shapes (NNS) of parts and components. Cold spray scientists have been involved in development of many applications in various high tech industries including aerospace, nuclear, power generation, etc. Unfortunately, most of these applications are proprietary and are not reported in open literature. Only a few applications have been presented in open literature and this presentation discusses some of the applications that have been developed.