Plasma sprayed thermal barrier coatings: Effects of polyamide additive on injection molding part quality

Abstract

A simple and economic atmospheric plasma spraying method for thermal barrier coatings (TBCs) preparation on the mold cavity was developed to improve the injection parts properties. 7 wt% yttria stabilized zirconia was used as spray material with polyamide 11 (PA 11) as pore‐forming agents to improve the coating properties. The effect of PA 11 powder contents on the microstructure, thermal conductivity, bonding strength and hardness of TBCs were studied. The results show that the thermal conductivity of TBCs decreased with the addition of PA 11, and the bonding strength reached maximum of 21.38 MPa with 10% PA 11 addition. Further studies confirm that TBCs were able to maintain a high and stable temperature in the mold cavity due to its low thermal conductivity, validated by the elimination of the welding line. With TBCs, the average tensile strength and elongation at yield of the injection parts increased by 25.6% and 128%, respectively.

Adjusting the Performance Properties of Products Obtained by Injection Molding from Polyamide

“…At the same time, the effect of polyamide modification on their properties 21 and preliminary laser surface treatment, which positively affects adhesion, 22 is sufficiently studied. The influence of fillers on the physicochemical properties of polyamides is being actively investigated.…”