電磁鋼片特用高性能無鉻防蝕塗膜

Cr-Free Anti-corrosion Coating with High Performance for Electrical Steels

電磁鋼片（ES）是具有特殊電磁特性的鐵矽合金，在發電機、壓縮機、馬達、變壓器中扮演能量轉換的平台角色。由於耐蝕性、絕緣性、加工性等方面之需求，現今的電磁鋼片大多具有表面塗膜。目前電磁鋼片的塗膜可分為含鉻與無鉻兩大系統。含鉻塗膜雖然並不符合環保之潮流，但目前仍為ES主要的塗膜系統。為取代含鉻系統，無鉻塗膜之性能必須更加精進。本文探討高性能C6N8-2無鉻塗膜、並與無鉻C6N8-1以及含鉻C628兩種標準塗膜進行比較。C6N8-2不但明顯優於無鉻C6N8-1，在耐蝕性、絕緣性、底材附著性方面，也與C628含鉻塗膜相當或更佳。因此，除可滿足一般應用外，高性能C6N8-2無鉻塗膜亦可用於講求高效能之產品，以促進無鉻環保技術於電機系統上之推廣。

Electrical steels (ES) are alloys of Fe-Si with special electromagnetic properties, due to which ES can serve as a platform for energy transformation in power generators, compressors, motors and transformers. To gain anti-corrosion capability, electrical insulation, and workability, most modern ES coils are surface coated. Nowadays there are two main coating systems for ES, the chromium (Cr)-based and the Cr-free. So far the Cr-based coatings have been the standard for ES and are still dominant now, even though they are not environment-friendly in the manufacturing stage. And the performance of the Cr-free ES coatings must be elevated before taking place of the present Cr-based system in the market. In this paper, an advanced Cr-free ES coating, C6N8-2, is investigated and compared with C6N8-1 (Cr-free) and C628 (Cr-based) for benchmarking. C6N8-2 not only overwhelms C6N8-1 but also has performance as good as or even better than C628 in corrosion resistance, interlayer resistance, adherence to substrates. Therefore, C6N8-2 coating is expected to promote the application of environment-friendly Cr-free technologies in general-purpose as well as high-performance ES end products.