固溶处理温度对高硅锰铬镍奥氏体不锈钢晶间腐蚀的影响
|
摘要
利用光学显微镜(OM)、扫描电镜(SEM)及能谱仪(EDS)等对不同温度下固溶处理高硅锰奥氏体不锈钢(UNS S21800钢)的晶间腐蚀进行了研究,分析了固溶处理和固溶+敏化处理两种工艺下进行晶间腐蚀试验后试样的组织形貌及晶间腐蚀倾向。研究结果表明:固溶处理后进行晶间腐蚀的试样中,表面均未发现裂纹,900℃固溶处理试样其晶界处存在较多的第二相,在950℃时第二相颗粒数量明显减少,当温度达到1200℃时,晶界附近已难以观测到第二相颗粒;经固溶处理+675℃敏化处理后进行晶间腐蚀试验的试样中,900℃固溶处理试样表面观测到有晶间裂纹存在,而固溶温度在950℃及其以上温度的试样未出现晶间裂纹。形成晶间裂纹原因是由于900℃固溶处理试样经过敏化处理后晶界处析出了更多的球状和长条状的富Cr碳化物,使得晶界附近区域形成了贫铬区,发生了晶间腐蚀;而950～1200℃固溶处理+敏化处理试样由于在固溶过程中第二相已大量溶入基体,虽然在敏化过程有部分析出,但不足以形成贫铬区,因此在该温度区间内难以发生晶间腐蚀行为。
The intergranular corrosion of high silicon manganese austenitic stainless steel( UNS S21800) at different solution temperatures was studied by means of optical microscopy( OM),scanning electron microscopy( SEM) and energy dispersive spectroscopy( EDS). The microstructure and intergranular corrosion tendency of the samples after intergranular corrosion test were analyzed under solution treatment or solid solution + sensitization treatment. The results show that there are no cracks observed on the surface of the intergranular corrosion specimens after solid solution treatment. There are more second phases observed at the grain boundary of the 900 ℃ solution treatment and the number of particles of the second phase is significantly reduced at 950 ℃. When the temperature reaches 1200 ℃,it is difficult to observe the second phase particles near the grain boundary; The intergranular crack is observed on the surface of the solution treated at 900 ℃among the specimens which employ intergranular corrosion test after solution treatment + 675 ℃ sensitization treatment. However,the intergranular crack doesn't occur in the specimen with a solution temperature at 950 ℃ or higher. The reason for the intergranular crack is that the spheroidal and long strips of( Cr,C) compounds are precipitated at the grain boundary after the sensitization treatment at 900 ℃,which makes the region of chromium delete near the grain boundary,and intergranular corrosion occurs. The solution treatment at 950-1200 ℃+ sensitization treatment sample has been dissolved into the matrix in the solid solution process. Although it is analyzed in the sensitization process,it is not enough to form a chromium-depleted zone. So the intergranular corrosion behavior is hard to occur in this temperature range.
The intergranular corrosion of high silicon manganese austenitic stainless steel( UNS S21800) at different solution temperatures was studied by means of optical microscopy( OM),scanning electron microscopy( SEM) and energy dispersive spectroscopy( EDS). The microstructure and intergranular corrosion tendency of the samples after intergranular corrosion test were analyzed under solution treatment or solid solution + sensitization treatment. The results show that there are no cracks observed on the surface of the intergranular corrosion specimens after solid solution treatment. There are more second phases observed at the grain boundary of the 900 ℃ solution treatment and the number of particles of the second phase is significantly reduced at 950 ℃. When the temperature reaches 1200 ℃,it is difficult to observe the second phase particles near the grain boundary; The intergranular crack is observed on the surface of the solution treated at 900 ℃among the specimens which employ intergranular corrosion test after solution treatment + 675 ℃ sensitization treatment. However,the intergranular crack doesn't occur in the specimen with a solution temperature at 950 ℃ or higher. The reason for the intergranular crack is that the spheroidal and long strips of( Cr,C) compounds are precipitated at the grain boundary after the sensitization treatment at 900 ℃,which makes the region of chromium delete near the grain boundary,and intergranular corrosion occurs. The solution treatment at 950-1200 ℃+ sensitization treatment sample has been dissolved into the matrix in the solid solution process. Although it is analyzed in the sensitization process,it is not enough to form a chromium-depleted zone. So the intergranular corrosion behavior is hard to occur in this temperature range.
引文
[1]葛晶,任中育.奥氏体不锈钢晶间腐蚀原因分析和对策[J].四川化工,2015,18(5):28-30.Ge Jing,Ren Zhongyu.Austenitic stainless steel intergranular corrosion cause analysis and countermeasures[J].Sichuan Chemical Industry,2015,18(5):28-30.
[2]Kasparova O V,Baldokhin Y V.New concept of the mechanism of intergranular corrosion of stainless steels[J].Protection of Metals,2007,43(3):235-240.
[3]Hwang E R,Kang S G.Intergranular corrosion of stainless steels in molten carbonate salt[J].Journal of Materials Science Letters,1997,16(16):1387-1388.
[4]阮於珍,张振灿,褚凤敏,等.316型不锈钢的晶间腐蚀性能[J].物理测试,2000(6):4-6.Ruan Yuzhen,Zhang Zhencan,Chu Fengmin,et al.Intergranular attack behavior of 316 type stainless steel[J].Physics Examination and Testing,2000(6):4-6.
[5]梁成浩.奥氏体不锈钢的晶间腐蚀[J].辽宁化工,1986(2):41-49.Liang Chenghao.Intergranular corrosion of austenitic stainless steel[J].Liaoning Chemical Industry,1986(2):41-49.
[6]陈炎.奥氏体不锈钢的晶间腐蚀[J].化工管理,2013(14):152.Chen Yan.Intergranular corrosion of austenitic stainless steel[J].Chemical Enterprise Management,2013(14):152.
[7]陈思含,梁田,张龙,等.6%Si高硅奥氏体不锈钢固溶处理过程中bcc相的演变机制研究[J].金属学报,2017,53(4):397-405.Chen Sihan,Liang Tian,Zhang Long,et al.Study on evolution mechanism of bcc phase during solution treatment in 6%Si high silicon austenitic stainless steel[J].Acta Metallurgica Sinica,2017,53(4):397-405.
[8]刘焕安.硫酸用不锈钢研究发展综述[J].硫酸工业,1999(1):1-16.Liu Huan'an.A survey of research and development of stainless steels for sulphuric acid service[J].Sulphuric Acid Industry,1999(1):1-16.
[9]邱德良,刘焕安,赵成永.DS-1高硅奥氏体不锈钢板在硫酸工业中的应用[J].硫磷设计与粉体工程,2005(1):18-23.Qiu Deliang,Liu Huan'an,Zhao Chengyong.Application of DS-1 high silicon austenitic stainless steel plate in the sulfuric acid industry[J].Sulphur Phosphorus and Bulk Materials Handling Related Engineering,2005(1):18-23.
[10]李伟,奚泉,张怡典.18-8型奥氏体不锈钢焊接热裂纹的分析[J].机械制造文摘-焊接分册,2014,44(6):23-24.Li Wei,Xi Quan,Zhang Yidian.Analysis of welding hot crack of 18-8 austenitic stainless steel[J].Mechanical Manufacturing Abstracts Welding Volume,2014,44(6):23-24.
[11]文玉华,张万虎,司海涛,等.高Si奥氏体高Mn钢加工硬化行为及机制的研究[J].金属学报,2012,48(10):1153-1159.Wen Yuhua,Zhang Wanhu,Si Haitao,et al.Stduy on work hardening behaviour and mechanism of high silicon austenitic high manganese steel[J].Acta Metallurgica Sinica,2012,48(10):1153-1159.
[12]张述林,李敏娇,王晓波,等.18-8奥氏体不锈钢的晶间腐蚀[J].中国腐蚀与防护学报,2007,27(2):124-128.Zhang Shulin,Li Minjiao,Wang Xiaobao,et al.Intergranular corrosion of 18-8 Austenitic stainless steel[J].Journal of Chinese Society for Corrosion and Protection,2007,27(2):124-128.
[13]张根元,吴晴飞.固溶处理温度对304奥氏体不锈钢敏化与晶间腐蚀的影响[J].腐蚀与防护,2012,33(8):695-698.Zhang Genyuan,Wu Qingfei.Influence of solution treatment temperature on sensitization of 304 austenitic stainless steel[J].Corrosion and Protection,2012,33(8):695-698.
[14]Sahlaoui H,Sidhom H,Philibert J.Prediction of chromium depletedzone evolution during aging of Ni-Cr-Fe alloys[J].Acta Materialia,2002,50(6):1383-1392.
[15]屈兴胜,林成,刘志林.奥氏体不锈钢晶间腐蚀[J].辽宁工业大学学报(自然科学版),2007,27(1):45-46.Qu Xingsheng,Lin Cheng,Liu Zhilin.Intergranular corrosion of austenitic stainless steel[J].Journal of Liaoning Institute of Technology,2007,27(1):45-46.
[16]李俊梅.奥氏体不锈钢的晶间腐蚀及保护[J].磷肥与复肥,1999(3):73-75.Li Junmei.Intercrystalline corrosion and protection of austenitic stainless steel[J].Phosphate and Compound Fertilizer,1999(3):73-75.
[17]赵莉萍,袁雪,李钊,等.热处理对低镍铬锰氮奥氏体不锈钢晶间腐蚀的影响[J].金属热处理,2015,40(7):37-41.Zhao Liping,Yuan Xue,Li Zhao,et al.Effect of heat treatment on intergranular corrosion of low Ni-Cr-Mn-N austenitic stainless steel[J].Heat Treatment of Metals,2015,40(7):37-41.
[2]Kasparova O V,Baldokhin Y V.New concept of the mechanism of intergranular corrosion of stainless steels[J].Protection of Metals,2007,43(3):235-240.
[3]Hwang E R,Kang S G.Intergranular corrosion of stainless steels in molten carbonate salt[J].Journal of Materials Science Letters,1997,16(16):1387-1388.
[4]阮於珍,张振灿,褚凤敏,等.316型不锈钢的晶间腐蚀性能[J].物理测试,2000(6):4-6.Ruan Yuzhen,Zhang Zhencan,Chu Fengmin,et al.Intergranular attack behavior of 316 type stainless steel[J].Physics Examination and Testing,2000(6):4-6.
[5]梁成浩.奥氏体不锈钢的晶间腐蚀[J].辽宁化工,1986(2):41-49.Liang Chenghao.Intergranular corrosion of austenitic stainless steel[J].Liaoning Chemical Industry,1986(2):41-49.
[6]陈炎.奥氏体不锈钢的晶间腐蚀[J].化工管理,2013(14):152.Chen Yan.Intergranular corrosion of austenitic stainless steel[J].Chemical Enterprise Management,2013(14):152.
[7]陈思含,梁田,张龙,等.6%Si高硅奥氏体不锈钢固溶处理过程中bcc相的演变机制研究[J].金属学报,2017,53(4):397-405.Chen Sihan,Liang Tian,Zhang Long,et al.Study on evolution mechanism of bcc phase during solution treatment in 6%Si high silicon austenitic stainless steel[J].Acta Metallurgica Sinica,2017,53(4):397-405.
[8]刘焕安.硫酸用不锈钢研究发展综述[J].硫酸工业,1999(1):1-16.Liu Huan'an.A survey of research and development of stainless steels for sulphuric acid service[J].Sulphuric Acid Industry,1999(1):1-16.
[9]邱德良,刘焕安,赵成永.DS-1高硅奥氏体不锈钢板在硫酸工业中的应用[J].硫磷设计与粉体工程,2005(1):18-23.Qiu Deliang,Liu Huan'an,Zhao Chengyong.Application of DS-1 high silicon austenitic stainless steel plate in the sulfuric acid industry[J].Sulphur Phosphorus and Bulk Materials Handling Related Engineering,2005(1):18-23.
[10]李伟,奚泉,张怡典.18-8型奥氏体不锈钢焊接热裂纹的分析[J].机械制造文摘-焊接分册,2014,44(6):23-24.Li Wei,Xi Quan,Zhang Yidian.Analysis of welding hot crack of 18-8 austenitic stainless steel[J].Mechanical Manufacturing Abstracts Welding Volume,2014,44(6):23-24.
[11]文玉华,张万虎,司海涛,等.高Si奥氏体高Mn钢加工硬化行为及机制的研究[J].金属学报,2012,48(10):1153-1159.Wen Yuhua,Zhang Wanhu,Si Haitao,et al.Stduy on work hardening behaviour and mechanism of high silicon austenitic high manganese steel[J].Acta Metallurgica Sinica,2012,48(10):1153-1159.
[12]张述林,李敏娇,王晓波,等.18-8奥氏体不锈钢的晶间腐蚀[J].中国腐蚀与防护学报,2007,27(2):124-128.Zhang Shulin,Li Minjiao,Wang Xiaobao,et al.Intergranular corrosion of 18-8 Austenitic stainless steel[J].Journal of Chinese Society for Corrosion and Protection,2007,27(2):124-128.
[13]张根元,吴晴飞.固溶处理温度对304奥氏体不锈钢敏化与晶间腐蚀的影响[J].腐蚀与防护,2012,33(8):695-698.Zhang Genyuan,Wu Qingfei.Influence of solution treatment temperature on sensitization of 304 austenitic stainless steel[J].Corrosion and Protection,2012,33(8):695-698.
[14]Sahlaoui H,Sidhom H,Philibert J.Prediction of chromium depletedzone evolution during aging of Ni-Cr-Fe alloys[J].Acta Materialia,2002,50(6):1383-1392.
[15]屈兴胜,林成,刘志林.奥氏体不锈钢晶间腐蚀[J].辽宁工业大学学报(自然科学版),2007,27(1):45-46.Qu Xingsheng,Lin Cheng,Liu Zhilin.Intergranular corrosion of austenitic stainless steel[J].Journal of Liaoning Institute of Technology,2007,27(1):45-46.
[16]李俊梅.奥氏体不锈钢的晶间腐蚀及保护[J].磷肥与复肥,1999(3):73-75.Li Junmei.Intercrystalline corrosion and protection of austenitic stainless steel[J].Phosphate and Compound Fertilizer,1999(3):73-75.
[17]赵莉萍,袁雪,李钊,等.热处理对低镍铬锰氮奥氏体不锈钢晶间腐蚀的影响[J].金属热处理,2015,40(7):37-41.Zhao Liping,Yuan Xue,Li Zhao,et al.Effect of heat treatment on intergranular corrosion of low Ni-Cr-Mn-N austenitic stainless steel[J].Heat Treatment of Metals,2015,40(7):37-41.