含矽不銹鋼之高溫塵化性質研究

A study on High Temperature Metal Dusting Behavior of Siliconized Stainless Steel

本研究以包覆擴散製程對AISI 304不銹鋼施以矽化處理，在其表面製作含矽不銹鋼擴散披覆層，探討此擴散披覆層對於高溫塵化之影響。將未施以表面研磨或經過表面研磨之矽化不銹鋼分別置入管形爐中，通入CO - CO2混合氣體，在700℃之溫度下，進行500小時長時間暴露試驗。試驗結果發現，在高溫及高碳勢的混合氣體中曝露後，未施以表面研磨之矽化不銹鋼表面可觀察到大量的碳沈積，而在其下的金屬層表面則有蝕孔生成。此蝕孔的生成是發生塵化反應的結果。至於經過表面研磨後之矽化不銹鋼，在曝露試驗後，其碳沈積現象較輕微，且金屬表面無蝕孔生成。

The high temperature metal dusting behaviors of siliconized AISI 304 stainless steels in mixed CO/CO2 atmosphere at 700℃ were investigated. Siliconization was achieved by performing pack cementation treatment. The experimental results showed that a thick carbon deposit was found on the specimen surface of each of the as-pack treated siliconized stainless steels after exposing in high temperature and high carbon activity gas atmosphere. Under the deposit, pits resulting from metal dusting reaction were found on the metal surface. By grinding off the surface compound formed during pack cementation, less carbon was deposited on the surface of the siliconized stainless steels. No pits were found on the metal surface of such specimens.