Numerical Investigation of Particles in Warm-Particle Peening-Assisted High-Velocity Oxygen Fuel (WPPA-HVOF) Spraying
- PDF / 2,394,326 Bytes
- 13 Pages / 595.276 x 790.866 pts Page_size
- 110 Downloads / 193 Views
PEER REVIEWED
Numerical Investigation of Particles in Warm-Particle PeeningAssisted High-Velocity Oxygen Fuel (WPPA-HVOF) Spraying Zhidan Zhou1,2,3 Xiubing Liang1
•
Yongxiong Chen1 • Zhenfeng Hu1 • Baolong Shen3,4
•
Submitted: 17 March 2020 / in revised form: 12 May 2020 Ó ASM International 2020
Abstract Shot peening was induced by utilizing the particles that flow out of the nozzle in a WPPA-HVOF process. For investigation of the peening particles, a model was built to simulate the HVOF spraying process including the temperature, velocity, pressure field of the flame, and the reaction of kerosene oxidation. The effect of incident velocity, incident position, and the diameter on the in-flight particle was presented. Incident velocity is an important factor for the synchronization of shot peening and coating deposition. The critical velocity was introduced to describe the particle state after hitting onto the substrate. The velocity and temperature of small particles injected in the barrel were measured experimentally to verify the model reliability. Experimental results reveal that the particle injected in the barrel deposited onto the substrate and the particle injected out of the nozzle rebounded, which agrees well with the predicted result.
& Baolong Shen [email protected] & Xiubing Liang [email protected] 1
Academy of Military Science PLA China, National Innovation Institute of Defense Technology, Beijing 100071, China
2
Institute of Massive Amorphous Metal Science, School of Chemistry and Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, China
3
School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China
4
School of Materials Science and Engineering, Jiangsu Key Laboratory for Advanced Metallic Materials, Southeast University, Nanjing 211189, China
Keywords HVOF in-flight particles numerical model shot peening thermal spray
Introduction High-velocity oxygen fuel (HVOF) spray process has been developed continuously and the field has grown steadily after its first application in the beginning of the 1980s (Ref 1). In the HVOF process, high pressure is generated in the combustor by the burning of the fuel and a supersonic flame flow with a temperature of * 3000 °C is generated after undergoing a converging–diverging (C-D) nozzle. Particles are heated and accelerated to high velocity after being injected into the flame. These particles hit the substrate or the preformed layer to form a coating with high density, low porosity, and oxide content (Ref 2, 3). Residual stress is a critical factor in evaluating the coating performance such as wear and corrosion resistance, bonding strength, and service life (Ref 4, 5). Three main aspects contribute to residual stress during the thermal spray process: shock stress due to high-speed semi- or un-melted particles impacting onto the substrate, quenching stress due to particles cooling down to deposited temperature, mismatch stress due to the different thermal expansion co
Data Loading...
