tailieunhanh - Báo cáo vật lý: "Effect of Temperature on Corrosion Behavior of AISI 304 Stainless Steel with Magnesium Carbonate Deposit"

Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: Effect of Temperature on Corrosion Behavior of AISI 304 Stainless Steel with Magnesium Carbonate Deposit | Journal of Physical Science Vol. 19 2 137-141 2008 137 Effect of Temperature on Corrosion Behavior of AISI 304 Stainless Steel with Magnesium Carbonate Deposit Habsah Md Ishak M. Misbahul Amin and Mohd Nazree Derman School of Material Engineering Universiti Malaysia Perlis Kompleks Jejawi 2 Taman Muhibbah 02600 Jejawi Perlis Malaysia Corresponding author habsah70@ Abstract The effect of temperature on corrosion behavior of AISI304 stainless steel was investigated in the presence of magnesium carbonate MgCO3 salt at 900oC 950oC and 1000 C for 24-120 h. The results indicated that the initial carbonate coating caused acceleration in oxidation resulting in the formation of scales followed by the decreased in oxidation rate due to evaluation of CO CO2 gas. The mass change of metal increased as the temperature and time exposure increased. The morphological structures of deposits were analyzed by using a scanning electron microscopy SEM . Keywords corrosion austenitic stainless steel deposit 1. INTRODUCTION Austenitic stainless steel type AISI 304 is extensively and widely used in petrochemical thermal power plants boiler part pressure vessel etc. because of their improved corrosion resistance at ordinary temperatures and conditions. However at high temperature and in oxidizing or hazardous atmosphere the surface of the alloy is seriously attacked resulting in the formation of Cr2O3 NiO or Fe2O3 The molten carbonate are diffused to the electrolytic matrix resulting the formation of porous The formation of alkaline scales strongly depends on temperature pH the rate of CO2 release as well as the concentrations of carbonates Several works have been reported5-6 on the studies of deposits on the AISI 304 alloy. However the study on the carbonate deposit at high temperature is not yet reported. In this work the corrosion behavior of commercial AISI 304 stainless steel with the presence of MgCO3 deposit at temperature 900oC -1000oC for the .