Search
Filters
Close

51317--9785-Oxidation Kinetics of Cast Alumina-Forming Austenitic Alloys in Steam

Alloy tubes used in petrochemical processing reactor systems are often subjected to oxidizing conditions in high temperature steam such as during de-coking cycles. A new class of heat resistant austenitic cast alloys are being developed that are designed to form protective oxides of alumina.

Product Number: 51317--9785-SG
ISBN: 9785 2017 CP
Author: Benjamin Church
Publication Date: 2017
Industry: Petroleum Refining
$0.00
$20.00
$20.00

Alloy tubes used in petrochemical processing reactor systems are often subjected to oxidizing conditions in high temperature steam such as during de-coking cycles. The ability of the alloy to form an adherent and continuous oxide layer is critical to ensure the material resists coking and other high-temperature attack during operation. A new class of heat resistant austenitic cast alloys are being developed that are designed to form protective oxides of alumina. Experimental compositions based on a 25Cr 35Ni base composition with aluminum contents ranging from 2.6 to 3.9 wt% were fabricated via centrifugal casting. An environment of pure steam was constructed in which samples were exposed at temperatures up to 1000 °C. Oxide layers were characterized by surface and cross-sectional electron microscopy and x-ray diffraction. Oxidation charts for determining the thickness of the oxide layer were constructed based upon the time temperature and aluminium composition of the alloy. Optimal times and temperatures for oxidation processing based on each material were determined.

Key words: Stainless Steel, Austenitic Alloy, High Temperature Oxidation, Coking, Alumina

 

Alloy tubes used in petrochemical processing reactor systems are often subjected to oxidizing conditions in high temperature steam such as during de-coking cycles. The ability of the alloy to form an adherent and continuous oxide layer is critical to ensure the material resists coking and other high-temperature attack during operation. A new class of heat resistant austenitic cast alloys are being developed that are designed to form protective oxides of alumina. Experimental compositions based on a 25Cr 35Ni base composition with aluminum contents ranging from 2.6 to 3.9 wt% were fabricated via centrifugal casting. An environment of pure steam was constructed in which samples were exposed at temperatures up to 1000 °C. Oxide layers were characterized by surface and cross-sectional electron microscopy and x-ray diffraction. Oxidation charts for determining the thickness of the oxide layer were constructed based upon the time temperature and aluminium composition of the alloy. Optimal times and temperatures for oxidation processing based on each material were determined.

Key words: Stainless Steel, Austenitic Alloy, High Temperature Oxidation, Coking, Alumina

 

Also Purchased