固溶处理温度对Fe-Mn-Al-C铁素体基轻质钢耐蚀性能的影响  

Influence of solution temperature on corrosion resistance of Fe-Mn-Al-C ferrite based light weight steel

作　　者：赵婷 孙佳振 贾鑫 郭凯 王天生[1,2] Zhao Ting;Sun Jiazhen;Jia Xin;Guo Kai;Wang Tiansheng(State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao Hebei 066004,China;National Engineering Research Center for Equipment and Technology of Cold Strip Rolling,Yanshan University,Qinhuangdao Hebei 066004,China)

机构地区：[1]燕山大学亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004 [2]燕山大学国家冷轧板带装备及工艺工程技术研究中心,河北秦皇岛066004

出　　处：《金属热处理》2021年第4期105-111,共7页Heat Treatment of Metals

摘　　要：利用光学显微镜、扫描电镜、X射线衍射仪等研究了热轧态、850、950和1050℃固溶处理Fe-Mn-Al-C铁素体基轻质钢的微观组织。通过测试固溶处理试样的极化曲线和阻抗曲线,以及观察试样在3.5%NaCl溶液中腐蚀后的表面状态,分析其耐蚀性。结果表明,试样经850℃固溶处理后的组织为铁素体+κ碳化物;950℃固溶处理后组织为铁素体+奥氏体+少量κ碳化物;1050℃固溶处理后组织为铁素体+奥氏体。随固溶处理温度的升高,试样中κ碳化物逐渐粗化直至全部溶解,950℃时发生奥氏体转变且晶粒有所增大,但1050℃时奥氏体的含量却略有降低。950℃固溶处理试样在3.5%NaCl溶液中的耐蚀性最佳,其自腐蚀电流密度为3.102×10^(-6)A/cm^(2),钝化膜的电阻Rp值为3944Ω。经过240 h腐蚀浸泡后,950℃固溶处理试样的腐蚀速率最低,这主要是由于其组织中奥氏体含量相对较高、铁素体和κ碳化物含量相对较低以及铁素体中Al元素含量较高所致。Microstructure of a Fe-Mn-Al-C ferrite based lightweight steel after hot-rolling and solution treatment at 850,950 and 1050℃,respectively,were analysed by means of OM,SEM and X-ray diffractometer.The corrosion resistance of the solution treated samples were studied by obtaining the polarization curves,impedance curves and the surface states corrosion in 3.5%NaCl solution.The results show that the microstructure after solution treatment at 850,950 and 1050℃are ferrite+κcarbide,ferrite+austenite+a littleκcarbide and ferrite+austenite,respectively.With the solution treatment temperature increasing,κcarbides coarse gradually until dissolve completely,austenite forms and the grain grows,but the amount of the austenite decreases slightly.The best corrosion resistance in 3.5%NaCl solution is obtained after solution treatment at 950℃,which self corrosion current density is 3.102×10^(-6)A/cm^(2)and resistance Rp value of passivation film is 3944Ω,the corrosion rate is lowest after corrosion test for 240 h.All of that is mainly due to the higher content of austenite and Al in ferrite as well as the lower content of ferrite andκcarbide.

关 键 词：Fe-Mn-Al-C铁素体基轻质钢 固溶处理 微观组织 耐蚀性 

分 类 号：TG172.5[金属学及工艺—金属表面处理]