HVOF has been widely used for producing dense coatings with high bond strengths. To reduce oxidation and/or decomposition of coatings, continuous efforts are being made to regulate the gas stream temperature. This paper presents a new combustion-based high pressure spray device that can spray fine powder materials at temperatures between those used in cold spray and HVOF. Temperature regulation is achieved by mixing combustion products with cold nitrogen in a mixing chamber. The warm gas mixture is then forced through a laval nozzle to generate a supersonic flow for particle acceleration and heating. The chamber pressure is up to 1.5 MPa, and temperature of the gas mixture is between 1000-2500 K. Coatings produced with the new device were characterized, and the effects of operating conditions on the coating quality were discussed.