Erosion behaviour of alumina ceramic coating on mild steel by the modified composition of phosphate binder

Abstract

The Pulverizer pipe made of mild steel had erosion failure due to coal dust impacting, thus its service life also reduces. The ceramic coating overlay on the surface of mild steel is one of the appropiate ways to protect the mild steel from erosion. This research is aimed to perform a ceramic coating over the surface of the mild steel using a dipping method to improve its erosion resistance by using the alumina-phosphate ceramic coating. The coating layer is formed by the reaction between monoaluminum phosphate (MAP) as a binder and Al2O3 particles. It transforms into berlinite phase when heated at an elevated temperature. The observation is carried out with the variation of the MAP binder composition Al:P 25:75, 28:72, 30:70 and the Al2O3/MAP slurry is given at 40/60. Scanning electron microscopy is used to characterize the coating morphology. X-ray diffraction is applied to investigate the ceramic coating phases. The gas erosion jet measures erosion resistance of the ceramic coating. From the test result, it can be concluded that the binder composition influenced the erosion behaviour of alumina ceramic coating, the binder with Al:P (30:70) showed the erosion resistance increasing four times compared to the condition without coating.

Fluidization‐based chemical vapour deposition for alumina coating on tubular carbon steel substrates—Modelling and validation

“…The generic rate equation for precursor decomposition on the carbon steel substrate is given by Equation (34) where S ½ , the concentration of active sites, is available for chemisorption at any instant of time and C AA surf is the concentration of precursor vapour in the gas phase of emulsion in contact with the substrate surface.…”

“…Rearrangement of Equation (36) gives Equation ( 37) to obtain C AA surf in terms of concentration of precursor vapour in gas phase of local emulsion C AA emul . Substituting this value of C AA surf in Equation (34) gives Equation (38).…”

“…[27] The general techniques used for alumina coating on carbon steels are physical vapour deposition, chemical vapour deposition (CVD), sol-gel, plasma electrolytic oxidation, thermal spray, and pack cementation. [27][28][29][30][31][32][33][34][35][36][37][38] In the present work, a fluidizationbased CVD process is employed owing to its ability to achieve simultaneous deposition of alumina on inner and outer surfaces of a tubular carbon steel substrate. Fluidized bed sublimation and induction heating are employed to optimize precursor inventory.…”

Pengaruh Waktu Heat Treatment Terhadap Karakteristik Ceramic Coating Berpengikat Fosfat pada Baja Karbon Rendah

“…Material St-37 digolongkan sebagai baja karbon rendah memiliki form ability yang baik, karena memiliki matrix ferritic [1]. Namun, material St-37 memiliki ketahanan erosi yang rendah dengan nilai erosion rate sebesar 20 mg/Kg [2]. Ketahanan erosi dan korosi yang rendah sering menjadi masalah dalam penggunaan material St-37 terutama dalam industri penanganan batu bara, seperti komponen sistem konversi batu bara, grinding equipment dan transport pipelines.…”

“…Berdasarkan hasil penelitian Idamayanti dkk[2],[6] didapatkan nilai erosion rate ceramic coating berpengikat fosfat dengan penambahan partikel SiC -Al2O3 sebesar 5 mg/Kg dan tanpa partikel SiC sebesar 8 mg/Kg. Idamayanti dkk[2],[6] membuat ceramic coating berpengikat fosfat dengan proses heat treatment selama 5 jam.Lamanya proses heat treatment selama 5 jam kurang efisien apabila diaplikasikan di lapangan, karena terlalu lama. Oleh karena itu dilakukan penelitian yang berfokus pada pengaruh waktu heat treatment terhadap karakterisasi ceramic coating berpengikat fosfat dengan partikel SiC dan tanpa partikel SiC.…”