IMPROVING COLD SPRAYABILITY: MIXED METAL POWDERS

Tuesday, May 12, 2015: 4:20 PM
Room 102B (Long Beach Convention and Entertainment Center)
Prof. Stephen Yue , McGill University, Montreal, QC, Canada
Dr. Huseyin Aydin , McGill university, Montreal, QC, Canada
Dr. Phuong Vo , National Research Council Canada, Boucherville, Montreal, QC, Canada
Rosaire Mongrain , McGill University, Montreal, QC, Canada
Rajib barua , McGIll University, Montreal, QC, Canada
Dr. Richard Dolbec , Tekna Plasma Systems Inc, Sherbrooke, QC, Canada
As a general rule, the usual way to increase cold sprayability (i.e. increase the deposition efficiency and decrease the porosity) is to increase the 'intensity' of the cold spray parameters of gas pressure and temperature.  As well powder characteristics can be chosen to maximize the velocity and to decrease the critical velocity.    This paper describes a third approach; the use of 'additives' to improve cold sprayability.  It is well known that ceramic particles can help cold sprayability, possibly by tamping as well as clearing the nozzle.  In this work, the effect of mixing different metal powders is shown to increase deposition efficiency and decrease porosity in specific combinations.  The metal combinations describved are: Ti and Ti-6-4, stainless steel and Co-Cr alloy; stainless steel and pure iron; spherical tantalum and irregular tantalum and spherical tantalum of different size and hardness.  Each of these combinations reveal improvements of eiither deposition efficiency and porosity.
See more of: Cold Spray Processing 2
See more of: Fundamentals/R&D