渗氮-氧化复合热处理对钢件抗蚀性能的影响

钢件经渗氮－氧化复合热处理后，抗蚀性能大为提高。20钢试件在5％NaCl水溶液中的浸泡试验，全部表面锈蚀所需时间，未处理件是24h（呈红色）、氧化处理件是54h（呈红色）、渗氮处理是96h（呈黄色）、而复合处理件则长达365h（呈浅黄色）。40Cr钢试件油田污水浸泡试验20天的失重率，复合处理件是渗氛件的13．6％，是本处理件的7．3％。35CrMo钢试件油田污水浸泡8天后的失重率，如以来处理件作为100，复合处理件是1．08、渗氮件是20．2。

Effect of Combined Nitriding and Oxidation Treatment on the Corrosion Resistance of Steel Components

The corrosion resistance of steel components can be remarkably improved by combined nitriding and oxidation treatment. The time it takes for the surface of the component made by steel 20 to be completely rusteaten in 5% NaCl aqueous solution is 24 hrs if untreated (the surface becomes red), 54 hrs after oxidation(red),96 hrs after nitriding (yellow) and 365 hrs after combined nitriding and oxidation treatment (pale yellow)After 20 days' itnmersion of the 40Cr steel test piece in the waste water from oil fields, the loss-in-weight of the specirnen after combined treatment is only 13.6% of that after nitriding and 7. 3% of that of the untreated. Eight days' immersion test of 35CrMo steel in the same nuid shows that the weight loss of the specimen after combined treatment is only 1.08 and it is 20.2 for the nitrided specimen if that of the untreated specimen is established as 100.