To take advantage of the synergistic effects of Pt and Zr, a kind of Zr-doped, Pt-modified aluminide coating has been prepared by a hybrid process, first electroplating a Pt layer and then co-depositing Zr and Al elements by an above-the-pack process. The microstructure and isothermal oxidation behavior of the coating has been studied, using a Pt-modified aluminide coating as a reference. Resul...

In order to form model aluminide coatings for studying critical issues related to their high temperature oxidation and corrosion performance, a laboratory chemical vapor deposition (CVD) procedure is being used to more rigorously control the coating process in terms of composition, purity and microstructure. One ferritic (Fe-9Cr1Mo) and one austenitic alloy (304L) were selected as substrate mat...

A 0.5 μm thick layer of rhodium was deposited on the CMSX 4 superalloy by the electroplating method. The rhodium-coated superalloy was hafnized and aluminized or only aluminized using the Chemical vapour deposition method. A comparison was made of the microstructure, phase composition, and oxidation resistance of three aluminide coatings: nonmodified (a), rhodium-modified (b), and rhodiumand ha...

In order to determine the potential benefits and limitations of aluminide coatings, coatings made by chemical vapor deposition (CVD) on Feand Ni-base alloy substrates are being evaluated in various hightemperature environments. Testing of coatings on representative ferritic (Fe-9Cr-1Mo) and austenitic (type 304L stainless steel) alloys has found that high frequency thermal cycling (1h cycle tim...

Formation mechanism of silicon modified aluminide coating applied on a nickel base super alloy IN-738 LC by pack cementation process was the subject of investigation in this research. Study of the microstructure and compositions of the coating was carried out, using optical and scanning electron microscopes, EDS and X-ray diffraction (XRD) techniques. The results showed that due to low partial ...

One of the critical issues for the application of iron aluminide coatings is the loss of Al from the coating into the Fe-base substrate alloys which do not contain aluminum. The interdiffusion behavior between chemical vapor deposited (CVD) aluminide coatings and ferritic and austenitic substrates is being studied for times up to 10,000h in the temperature range of 500-800oC. Coatings were synt...

In this study, aluminide coating was employed to enhance the high-temperature cyclic oxidation of Rene-80 superalloy at 950ºC. The microstructural aspects and phase constituents of samples were  investigated with scanning electron microscopy (SEM) and x-ray diffraction (XRD) techniques. The result of oxidation tests showed that the weight gain in the uncoated sample was considerably higher than...

recent studies demonstrate that aluminide coatings are beneficial to wear and erosion resistance and also that oxygen-active elements such as yttrium can remarkably improve this resistance. in this research, the micro-hardness of the aluminide coatings with and without yttrium on 1045 steel was investigated using a micro-mechanical probe. wear of the samples was measured using a pin-on-disk tri...

Abstract: nanocrystalline nickel samples with the grain size of ~25 nm were prepared via direct current electrodeposition andaluminized for different durations by pack cementation method at 500 means of SEM, EDS and XRD techniques. According to results, short time aluminizing resulted in the formation of asingle aluminide layer whereas at long duration two distinct aluminide layers were formed....