The controllable parameters for each of the major thermal spray types are different, but all share some common fundamentals. Converting feedstock material (whether powder, wire, or rod) into a coating requires heat energy for melting and a gas flow for atomization and/or particle acceleration to propel the particles toward the substrate. Input heat energy and gas flow, in turn, directly influence process variables including flame/plasma/jet temperature and velocity; particle temperature, speed, and trajectory; and deposit temperature. Each of these variables affects spray-pattern formation and particle heating differently.

In general, combustion-flame, combustion-wire, and twin-wire arc spray coatings are generated from high heat input plus low particle velocity, producing coatings having high oxide content, a large number of rounded particles, and relatively high porosity. Due to higher particle velocity, superheated particles in plasma spray coatings are flattened more than in combustion spray coatings, producing denser coatings with finer porosity. Very high-velocity systems such as detonation gun and HVOF, combined with lower heat inputs, typically produce very dense coatings not achievable by the other processes.

TSS Regional Events

Aerospace Coatings Symposium
October 15-16 2008
Sheraton Bradley Hotel, Bradley (Connecticut) International Airport
Learn about some of the latest developments in thermal spray and other surface engineering technologies designed specifically for use in the aerospace industry.

Pre-Event Seminar
Materials and Processes for High Temperature Gas Turbine Components
October 13-14, 2008
Sheraton Bradley Airport
Instructor: Dr. Donald Boone, President, BWD Turbines Ltd., Walnut Creek, Calif.
Seminar focuses on thermal spray and other surface modification processes critical to the aerospace industry.

Symposium on Improving Reliability and Consistency in Thermal Spray
December 2-3, 2008
Hyatt Regency Montreal, Quebec, Canada
Presentations by invited speakers covering reliability and consistency of thermal spray processes and coatings, and poster session.

Sponsorships Available for Both Events
To learn more about tabletop exhibiting and sponsorship opportunities, or to discuss customizing a program to meet your specific needs, contact Kelly Thomas, Exposition Sales Manager (440-338-1733)