Effect of Silicon Content and Sintering Temperature on the Corrosion and High Temperature Oxidation Resistance of Sintered 303LSC-Si Stainless Steels

矽含量和燒結溫度對303LSC-Si 燒結不銹鋼之耐蝕性和抗高溫氧化性的影響

本文之研究目的在於探討矽粉末添加量和燒結溫度對燒結不銹鋼之耐蝕性和抗高溫氧化性的影響。實驗結果顯示：燒結不銹鋼之耐蝕性隨矽粉末添加量之增加和燒結溫度之提高而獲得改善，燒結合金施以振動珠擊處理後其耐蝕性能夠進一步增強。矽粉末添加量和燒結溫度會改變燒結合金之金相組織與表面形態，進而影響合金於腐蝕溶液中之耐蝕能力。燒結合金耐蝕能力獲得增強的原因為較多的矽粉末添加量會於微結構內引生較多的肥粒鐵相，同時，減少燒結合金的表面積。振動珠擊處理之冷作會封閉合金表面的小孔洞並使表面晶粒平坦化，進一步大幅地減少表面積。燒結合金於600ﾟC和800ﾟC之抗高溫氧化性隨矽粉末添加量之增加而增強，振動珠擊處理會減損燒結合金於600ﾟC之抗氧化性；然而，對於800ﾟC之抗氧化性則不會產生明顯的影響。

The corrosion resistance of sintered 303LSC alloys increases with increasing amount of added silicon powder and sintering temperature, and is further improved by the cold work of vibratory ball-peening. Silicon content and sintering temperature influence the microstructure and surface morphology, which effect a marked change in the corrosion resistance of sintered alloys. The improvement in corrosion resistance is resulted from the increasing ferrite content induced by introducing of more silicon powder and the decreasing surface area of well-sintered alloys. Cold work with vibratory ball-peening closes small surface pores and further reduces the surface area profoundly. The oxidation resistance at 600?C and 800?C in air increases with increasing silicon content. Treatment of vibratory ball-peening decreases the oxidation resistance of sintered alloys at 600?C.