Si-Mo-MODIFIED ALUMINIDE SLURRY COATING FOR HIGH TEMPERATURE PROTECTION OF AUSTENITIC STAINLESS STEEL

  • Syamimi Abu Kassim School of Materials and Minerals Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, Seberang Perai Selatan, 14300 Nibong Tebal, Pulau Pinang, Malaysia
  • Nur Muzirah Md Shukri School of Materials and Minerals Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, Seberang Perai Selatan, 14300 Nibong Tebal, Pulau Pinang, Malaysia
  • Syazana Ahmad Zubir School of Materials and Minerals Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, Seberang Perai Selatan, 14300 Nibong Tebal, Pulau Pinang, Malaysia
  • Anasyida Abu Seman School of Materials and Minerals Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, Seberang Perai Selatan, 14300 Nibong Tebal, Pulau Pinang, Malaysia
  • Tuti Katrina Abdullah School of Materials and Minerals Resources Engineering, Engineering Campus, Universiti Sains Malaysia, Seri Ampangan, Seberang Perai Selatan, 14300 Nibong Tebal, Pulau Pinang, Malaysia
Keywords: Aluminide coating, Aluminizing, Si-Mo-modified, Austenitic stainless steel, High-temperature protection

Abstract

Slurry aluminide coating is considered one of the most excellent coating materials to enhance hot corrosion resistance for high temperature applications. In this research, Si-, Mo- and Si-Mo-modified slurry aluminide coatings were prepared on 304 stainless steel at 650 ºC for 4 h and 6 h. The influence of Si, Mo and Si-Mo additions into the coatings was studied by comparing the coating properties at different aluminizing time. The physical, chemical and mechanical properties of the aluminide coatings were characterized using the Vickers microhardness test, FESEM, EDX and XRD. The addition of Si and Mo into the coating slightly changes the coating behaviour of the alloy. A multi-layered coating structure was observed after the aluminizing for all coating samples. A dense and continuous inner layer made up of FeAl-base intermetallic is believed to improve the corrosion resistance of the stainless steel. The hardness value (HV) increased with an increasing in aluminizing time for Mo- and Si-modified aluminide coatings. In contrast, Si-Mo-modified aluminide coating showed a decreased in hardness value (HV) due to the formation of multi-crack and porous coating structures. A modified slurry aluminide coatings on 304 stainless steel could be considered as a viable potential for high temperature application.

Published
2021-12-20
Section
Original Research Articles