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【答案】应助回帖
★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ★ ... phu_grassman: 金币+5, thanks for your kind help. 2013-02-27 13:31:17 zhingjw: 金币+50, 翻译EPI+1, ★★★★★最佳答案, 谢谢 2013-02-28 00:57:19
To solve the susceptibility of A's intergranular Nd-rich phase to electrolytic corrosion during surface electroplating, we proposed a double coating protection technique for A including phosphorization and copper plating, in other words, the A's intergranular phase is allowed to generate passive phosphorization products through phosphorizing process, folllowed by alkaline copper plating. The surface topography and corrosion resistance of the phosphorized A were observed using SEM and electrochemical method respectively. Based on the above data as well as EDS analysis results, the formation mechanism of the phosphorized film was discussed. For A that has been phosphorized and copper plated for a short time, sectional examination and corrosion resistance analysis were done. The results indicate that, the intergranular phase of A forms the phosphorization products preferably than the main crystal phase of A; just after a short time phosphorization, the A's intergranular phase has covered the phosphorization product and enabled the corrosion resistance of the magnetic body significantly improved. The main phosphorization products are Nd and Fe phosphates, and probably Nd oxides, and Nd content of the intergranular phase's phosphorized film is higher than that of the main crystal phase. With synergistic protection of A through intergranular phosphorization followed by copper electrodeposition, its corrosion resistance is significantly better than that with a single phosphorized film or single plating protection.  |
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