An ambient temperature phosphating technique under ultrasonic wave for sintered NdFeB was studied by surface morphology observation and corrosion tests. The optimum parameters of this technique are 60.0g/L Zn ( H2 PO4 ) 2, 100.0g/L Zn ( NO3 ) 2 · 6 H2O , 3.5 ～ 5.0g/L Ni( NO3 ) 2, 4.0g/L H3P04, 2.0g/L NaNO2, 1.0g/L NaF, 1.0 g/L tartaric acid, free acidity 3.0, total acidity 120.0,30℃ and 15min. The test results show that the time for the phosphating film withstanding CuSO4 drop corrosion test is up to 37s,and the time for occurring corrosion rust spot in 3％ NaCl solution immersion test is 6h. Compared with the process without ultrasonic wave, the phosphating film under ultrasonic wave is uniform and compact, and has a better corrosion resistance and a higher adhesion between phosphating film and cathodic electrophoresis film.%研究了烧结型NdFeB在常温超声磷化工艺,通过测试磷化膜的耐蚀性、表面形貌等性能,确定其工艺为:60.0g/L磷酸二氢锌;100.0g/L硝酸锌;3.5～5.0g/L硝酸镍;4.0g/L磷酸;2.0g/L亚硝酸钠;1.0g/L氟化钠;1.0g/L酒石酸;游离酸度3.0;总酸度120.0;θ为30℃;t为15min.所得磷化膜耐CuSO4点滴时间可达37s,在3%NaCl溶液中产生锈蚀点的时间为6h.与未加超声波的磷化工艺比较,所得磷化膜层均匀、致密、耐蚀性好,磷化膜与阴极电泳漆膜结合力好.
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