|
4705 |
|
Tuesday, May 10, 2016, Room 3E 2:40 PM New Processes I |
|
Coatings deposited using a valveless detonation gun system |
|
Robert Gansert / Advanced Materials & Technology Services, Inc., USA Rajan Bamola* / Surface Modification Systems Inc, USA Paul Robinson/ Surface Modification Systems Inc, USA Thomas Ewell/ Surface Modification Systems Inc, USA |
|
Detonation (e.g., D-Gun) Spraying is one of the oldest but least utilized thermal spray technologies. However, coatings are known to be harder and better adhered than those applied via plasma and even HVOF methods. Some of the reasons of the reasons for the lower popularity of D-gun spraying are the lower productivity and higher complexity of interaction between the equipment and powder. Much of this is due to the use of mechanical valving to feed in the combustion gases and therefore necessitating the use of intermittent powder flows. In this study we report on a new valveless Detonation spraying device allowing the use of continuous powder feeding and capable of higher detonation frequency then through conventional valved D-Gun systems. Previous valveless systems were unreliable in terms of firing and safety. A range of carbides, metallics and oxides were deposited and characterized microstructurally and mechanically to define the operating range for this new type of device. Typically, it was found that carbides and oxides were superior in terms of density and hardness than HVOF and plasma sprayed coatings, the metallic although dense did have higher oxide content. |