| 摘要 |
Method for applying a phosphate coating on an iron or steel part, and corresponding iron or steel part. The method according to the invention consists in a first coating step with a first phosphating, through which a first crystalline layer of iron and manganese phosphates is obtained, an intermediate step of partial pickling of said first crystalline layer of phosphates, leaving the base metal partially uncovered, and a second coating step comprising a second phosphating through which a second crystalline layer of iron and manganese phosphates is obtained, covering the partially pickled first layer of phosphates and the base metal. The method provides a coating with a lower thickness, a finer crystallisation and a lower rugosity Rk than the one that can be obtained by a simple phosphating.
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