Investigation of low-pressure cold-gas dynamic spraying of polyamide-12 (PA12) on steel surfaces

21st Chemnitz Seminar on Materials Engineering – 21. Werkstofftechnisches Kolloquium

Tillmann, W.^1 ; Zajaczkowski, J.F.^1

TU Dortmund University, Institute of Materials Engineering, Germany^1

关键词: Cold gas dynamic spray;    Cold gas dynamic spraying;    Continuous temperature;    Corrosive resistances;    Degradation temperatures;    Thermal spray technology;    Thermoplastic coatings;    Tribological properties;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/480/1/012009/pdf
DOI  :  10.1088/1757-899X/480/1/012009

来源: IOP

【 摘 要 】

Due to their good tribological properties and corrosive resistance, thermoplastic coatings are becoming increasingly important in industrial applications. Thermal spray technologies in general and flame spraying in particular belong to the most common application methods. However, the high thermal energy inevitably leads to the risk of thermal decomposition, especially in the case of materials such as polyamide-12, which have a small discrepancy between the melting and degradation temperatures. Furthermore, flame-sprayed coatings often are highly porous, reducing its effectiveness as a corrosive barrier. As an alternative approach, polyamide-12 coatings were applied to steel substrates using a conventional low-pressure cold-gas dynamic spray system. Various mixtures including ceramic powders (Al2O3) as well as different injection concepts were investigated and evaluated. The focus was put on the resulting coating morphology. Furthermore, the cold-gas spraying system was modified with a continuous temperature control for the gas temperature to enable a more precise adjustment based on the melting temperature of the material in order to reduce the risk of thermal degradation.