TWI Industrial Member Report Summary 947/2010
By T Marrocco
Background
Cold spray, or more precisely cold gas dynamic spraying (CGDS), is an innovative coating technology for the production of high quality metal-based coatings. The process involves the deposition of metallic layers and structures from fine powders, typically with size from 5 to 50µm, that are propelled using high pressure gases (1.5-4.0MPa). The particle temperature is maintained well below the melting temperature and, indeed, can be close to ambient temperature, hence the designation cold spray.
The cold spray process has reached a critical stage in its industrialisation, with proven commercial equipment now available, together with specially developed powders to ensure good coating quality.
This report is intended to serve as a guide to the technology, available systems and factors that should be considered in establishing a cold spray facility, for either end-users to gain confidence in the capability of the sub-contractor or for those contemplating establishing an in-house capability. It is based on TWI's experience in specifying, selecting, installing and commissioning a cold spray facility. At present, the CGT Kinetiks K4000/47 represents the most proven, fully flexible cold spray system capable of spraying a wide range of materials, with by far the most equipment sales and industrialisation. This is the system that formed the basis of the installation at TWI Yorkshire during Q1, 2007. The capital items of the cold spray facility at TWI Yorkshire were funded by the regional development authority, Yorkshire Forward, supported by Objective One funding through the Surface Engineering Group (SEG) programme.
Objective
Provide guidance to those considering the application of cold spray coatings and/or installation of a cold spray system, in terms of:
- Technological maturity and capability
- Commercialisation
- System availability
- Process economics