An alternative methods for poteyaj application with thermal spray thermal barrier coating application in low pressure die casting

Die coatings have been used for low pressure die casting of aluminium alloys for improved process performance for many decades. Essentially during low pressure and gravity die casting, the die cavity takes longer time to fill in compared with high pressure die casting, and as a result to prevent premature solidification of the casting alloy a thermal insulating coating is applied to the metallic die surface. The porous coating provides good thermal insulation and also provides protection from erosion and corrosion from contact with molten metal. However, these coatings are fragile and the wear properties are poor, requiring frequent costly and often in-situ maintenance to maintain the coating in service. These coating have a relatively short service life and production is frequently interrupted to replace the die coat after only afew shifts. In addition, maintaining cast product quality is difficult because as the die coating wears and reduces in thickness, the heat transfer alters changing the solidifying pattern of the aluminium alloy and porosity position. To improve productivity and reduce the production costs there was a need to develop a durable insulating die coat for low pressure die casting. Durability of a die coat is largely dependent on the bond strength and wear resistance. To achieve stronger bonding, thermal spraying techniques were considered. In this thesis project the new developed coatings performance for thermal sprayed (APS, Flame spray) MgO stabilized ZrO2 with polymer and BN particle reinforced coatings were investigated. The microstructure, surface and mechanical properties of the coatings are characterized and their appliciability is investigated and also compared by technically and economically depend on composition and spray method.