LC52铝合金抗剥落腐蚀性能研究

测定了LC52铝合金时效后的剥落腐蚀性能，并对该合金各种状态下的显微组织进行了TEM分析，研究了影响该合金腐蚀性能的主要因素以及显微组织与性能之间的关系。结果表明，LC52铝合金经RRA处理后，具有良好的抗剥落腐蚀性能。测试室温下不同时效状态LC52铝合金试样的恒电位极化曲线，发现可以以合金的极化电阻定性地描叙合金的抗剥落腐蚀性能，且当合金的极化电阻越大时，合金的抗剥落腐蚀性能越好。     

激光冲击喷丸对2195铝锂合金组织结构及抗应力腐蚀性能的影响

研究了激光冲击喷丸(LSP)对2195铝锂合金组织结构及抗应力腐蚀性能的影响。研究结果表明激光冲击处理后,2195铝锂合金表层晶粒细化到纳米量级,多次冲击能使表层晶粒进一步细化。残余应力测试结果表明激光冲击喷丸能够引入残余压应力,多次冲击后残余压应力数值更大。此外,应力腐蚀实验结果表明激光冲击喷丸能够有效提升2195铝锂合金的抗应力腐蚀性能。在应力腐蚀环境中,激光冲击喷丸诱生的表层残余压应力和晶粒细化层能够阻碍裂纹的萌生和扩展,防止应力腐蚀断裂。     

低合金高强度抗H2S应力腐蚀钻材钢的研究

“ＰＵ－１”低合金高强度抗Ｈ２Ｓ应力腐蚀钻材钢具有良好的综合力学性能和抗Ｈ２Ｓ应力腐蚀性能。对“ＰＵ－１”钢和焊缝合金断裂行为的研究结果表明,“ＰＵ－１”钻材钢抗Ｈ２Ｓ应力腐蚀性能和焊接性能较好,应用于结构钢构件具有显著的经济和社会效益。     

含锶钪2099型铝锂合金的晶间腐蚀和剥落腐蚀性能

采用维氏硬度计(HV)、金相显微镜(OM)和扫描电镜(SEM)显微分析技术,研究了一种锶钪复合微合金化2099型铝锂合金(其化学成分为:Al-2.57Cu-1.86Li-1.31Zn-0.420Mg-0.321Mn-0.0735Zr-0.0943Sr-0.0433Sc)的晶间腐蚀性能和剥落腐蚀性能。结果表明,该合金经均匀化退火处理(475℃×24 h)、热锻压变形加工处理(三次变形量均约为100%)、固溶处理(540℃×2 h)、冷水淬火(水温大约5℃)、T8时效处理(121℃×14 h+151℃×48 h)后,合金显微硬度值达到174.6 HV,比2024-T6合金(固溶处理500℃×2 h+时效处理191℃×12 h)高23.1%。合金具有良好的抗晶间腐蚀性能和抗剥落腐蚀性能,其抗腐蚀性能明显优于2024-T6合金。该合金Sr,Zr,Sc的复合微合金化作用(细化粗大第二相、抑制再结晶和晶粒长大),第二相分散、分布不连续,以及Zn的含量高,是合金抗腐蚀性能高的主要原因。研究结果还说明了微量复合添加对铝锂合金具有奇效微合金化作用的过渡族金属元素Sr,Sc,是得到抗腐蚀性能良好的铝锂合金的一种有效途径。     

7050超高强铝合金蠕变时效成形行为与性能研究

对7050超高强铝合金进行蠕变时效处理,采用维氏硬度、晶间腐蚀和剥落腐蚀等试验对其力学性能与腐蚀行为进行研究,采用光学显微镜和透射电子显微镜对微观组织进行观察,研究蠕变时效对合金微观组织与性能的影响。结果表明:合金的稳态蠕变速率随温度的升高和应力的增大而逐渐升高,时效温度是影响合金蠕变速率和抗腐蚀性能的主要因素。7050超高强铝合金的稳态蠕变速率与蠕变应力和蠕变温度的关系可以表示为:■=e~(12.226)σ~(1.66)exp(-120 536/RT)。蠕变时效处理后,合金的维氏硬度、抗晶间腐蚀和抗剥落腐蚀性能均得到提高。合金在120℃和140℃下蠕变时效后,维氏硬度和抗腐蚀性能都保持在较高的水平,160℃下合金的维氏硬度和抗腐蚀性能均较低。人工时效后,7050超高强铝合金中的主要强化相为大量弥散分布的η'相,蠕变时效后,晶内和晶界析出相尺寸略有减小,晶界析出相分布不连续,电化学腐蚀速率减小,合金抗腐蚀性能提高。     

合金元素对铝合金箔抗腐蚀性能的影响

为了制备具有良好抗腐蚀性能的铝合金抑爆材料,合成了4种含有不同合金元素的铝合金箔。采用化学腐蚀实验研究了4种铝合金箔在盐酸溶液中的腐蚀性能,并采用扫描电子显微镜(SEM)观察了腐蚀前后的表面结构变化。通过失重法测定了铝合金箔在酸溶液中的腐蚀速率,结合极化曲线测定结果,系统分析了合金元素对铝合金抗腐蚀性能的影响。分析结果表明,在评定铝合金箔的腐蚀速率时,化学腐蚀实验和动电位极化曲线测试具有较好的一致性。过渡元素在合金中形成不同的耐蚀相,可以有效提高铝合金箔的抗腐蚀性能。在实验结果的基础上初步探讨了合金元素对铝合金抗腐蚀性能的影响机制。通过综合分析得到优化后的合金元素添加量(质量分数)为1.15%Mn,0.30%Si,0.46%Fe,0.16%Cu,0.05%Zn,0.05%Ti,0.05%Cr,该组分的铝合金箔在酸性溶液中具有较好的抗腐蚀性,有望制备具有更好抗腐蚀性能的铝合金抑爆材料。     

Hastelloy B－2型铸造镍基合金的组织及其局部腐蚀行为研究

本文研究了一种能在高温盐酸苛刻介质中服役的低碳低铁型铸造Ｎｉ－Ｍｏ合金的组织及其局部腐蚀行为。通过金相显微镜、Ｘ射线衍射、电子探针和透射电镜与扫描电镜进行了金相组织分析，并采用快速模拟试验方法研究了该合金的局部腐蚀行为。试验结果表明，ＨａｓｔｅｌｌｏｙＢ－２型铸造镍基合金经１１８０℃×２ｈ水冷固溶处理后，其组织为全奥氏体时，该合金具有良好的耐晶间腐蚀性能和较高的抗点蚀性能。     

退火温度对冷轧5383铝合金组织及腐蚀性能的影响

通过力学性能、剥落腐蚀和极化曲线测试,研究了退火温度对淬火后冷轧5383铝合金组织及腐蚀性能的影响。结果表明:合金冷轧(60%变形量)再结晶温度为280℃;合金在150℃退火1h的5383铝合金,β相及相主要在晶界分布,合-7金具有较弱的抗腐蚀性(腐蚀腐蚀电压为-0.730V,腐蚀电流为9.004×10 A);在300℃退火1h后,β相及相在晶界和晶-8内呈均匀分布,合金具有较好的抗腐蚀性能(腐蚀电压为-0.604V,腐蚀电流为8.987×10 A);在350℃退火1h后,晶粒变-7粗,β相发生长大,合金抗腐蚀性能又减弱(腐蚀电压为-0.860V,腐蚀电流为8.212×10 A)。     

新型铁基合金材料在铝液中耐腐蚀性能的研究

研究新型铁基合金中组成对其抗铝液腐蚀性能的形响，探讨了合金在铝液中的腐蚀机理。实验结果表明：在影响铁基合金在铝液中抗腐蚀的诸因素中，石墨形态的影响是主要的，铬对合金抗腐蚀性能的负作用比较大，少量难对合金的抗腐蚀性能有较大负作用，在一定量以后，对合金的抗腐蚀性能有所改善，铜对合金的抗腐蚀性能影响较小。     

HastelloyG型铸造镍基合金组织及其腐蚀与磨蚀行为的研究

本文采用多种试验方法，研究了ＨａｓｔｅｌｌｏｙＧ型铸造镍基合金的组织及其腐蚀与磨蚀的行为。试验结果表明，该合金经１２００℃×２ｈ水冷固溶处理后，具有优良的均匀腐蚀、晶间腐蚀、点蚀、电化学腐蚀性能以及较好的抗磨蚀性能。     

低碳铌微合金钢在海水中的腐蚀规律

 铌钢主要用于大型船舶和海上工程建设，所以铌钢的耐海水腐蚀性能非常重要。研究了铌钢和不含铌钢在海水中不同腐蚀阶段的交流阻抗谱和腐蚀电位，获得了腐蚀过程的电荷传递电阻。研究结果表明：铌钢在海水腐蚀过程中的电荷传递电阻随腐蚀时间的延长而增大，其耐海水腐蚀性能优于不含铌钢。     

Strong bimetallic structural material alloyed with nitrogen

The production of strong two-layer steel sheet—a bimetallic structure with a basic layer of low-carbon manganese microalloyed bainitic steel and an applied layer of two-phase austenite–ferrite stainless steel alloyed with nitrogen—is considered. In trials, the production of bimetallic material on the basis of the electrical-arc surfacing is investigated: specifically, the application of high-alloy steel to a plane microalloyed steel blank, by means of welding wire (under a flux layer), with subsequent hot deformation. The trials include the simulation of forced sheet cooling on the exit conveyer of the broad-strip mill and slow cooling of the final coiled strip. The microstructure, mechanical strength, and corrosion resistance of the bimetallic structural material are investigated. The proposed material matches the corrosion resistance of existing bimetals. Its yield point and the adhesive strength of the two layers exceed those of traditional two-layer steel by at least 30–50% and are three times the standard requirements.     

Influence of Microalloying on the Strength and Corrosion of Low-Carbon Stainless Steel

Attention focuses on how nitrogen and rare-earth metals modify the mechanical properties and corrosion characteristics of unstabilized low-carbon Fe–Cr–Ni stainless steel, additionally alloyed with silicon and molybdenum. The influence of the selected microalloying method on the mechanical properties of unstabilized low-carbon chromonickel stainless steel and its resistance to local corrosion is studied experimentally. Nitrogen-bearing 03X17H9AC2, 03X17H9AM3, and 03X18H15AM3 stainless steel microalloyed with rare-earth metals is investigated.     

聚磁介质用不锈导磁材料开发

为了改善现有强磁选机聚磁介质耐磨、耐腐蚀能力,提高其聚磁性能,开展了聚磁介质用不锈导磁材料制备、显微组织观察、力学性能测试、耐腐蚀性能及磁性能测试试验。结果表明,利用真空熔炼炉进行钢水熔炼、热轧、完全退火处理后可制备出屈服强度为287 MPa、显微硬度为148HV、腐蚀速率为10-8 A/cm~2、背景场强为35A条件下的磁化磁场强度为14 000Gs、剩磁强度为1 056Gs的不锈导磁聚磁介质用材料。     

节镍无磁不锈钢Cr18Ni6Mn3N的组织及性能

研究了节镍无磁不锈钢Cr18Ni6Mn3N的热轧及固溶后的力学性能和耐蚀性能,分析了其固溶和时效析出后的组织演变规律、冷变形过程中形变诱发马氏体相变及其磁性能.结果表明:该不锈钢的固溶组织为单相奥氏体,其力学性能和耐蚀性能均高于SUS304不锈钢;800℃保温4 h后,在晶界析出粒状氮化物,随着保温时间延长,逐渐沿晶界凸起片层状析出物并向晶内生长,保温20 h后,凸出的片层状析出物直径达20μm.冷轧压下率18.3%时尚未发现形变诱发马氏体组织,随着变形量增大,马氏体含量增多,磁导率上升,但与相同条件下的SUS304不锈钢相比,冷轧板固溶后相对磁导率可降至1.002,因此可用于低成本无磁不锈钢领域.      

Mastering the Production of Rolled Products and Tubes of Steel 20-KSKh Guaranteed to Be Free of Corrosion-Active Nonmetallic Inclusions

Results obtained from comprehensive corrosion tests have established that in addition to limiting the content of corrosion-active nonmetallic inclusions in steel to make it resistant to corrosion, it is also desirable to restrict the steel's contents of sulfur, manganese, and silicon. The new specifications for steels 20-KS (corrosion-resistant) and 20-KSKh (corrosion- and cold-resistant) were therefore developed based on steel 20sp, which is distinguished by its relatively low contents of manganese and silicon. These steels also have a limited sulfur content, and they are microalloyed with niobium or vanadium to obtain a fine-grained structure. All the other indices of the steels meet the requirements of SNiP. Mastering the production of welded tubes made of steel 20-KSKh is an important step toward the goal of improving the durability of oil-field tubing in Western Siberia. Such tubes are the first type of tubular metal product that has been guaranteed to be clean with respect to corrosion-active nonmetallic inclusions, and guarantees of this kind are a prerequisite to ensuring that pipelines have satisfactory corrosion resistance and last for their normal service life. __________ Translated from Metallurg, No. 6, 43–48, June, 2005.     

铁路车辆用09CuPCrNi 耐大气腐蚀钢研制

介绍了铁路车辆用09CuPCrNi耐蚀钢的研制情况.采用合理的成分设计,将主要合金元素的质量分数控制在较低水平,使其具有良好的焊接性能和较低的生产成本;采用微合金元素强化工艺以提高钢的强度,使用大电炉冶炼加LF精炼以保证钢的纯净度.最终使钢的质量和性能全面达到铁道部新的铁路车辆用耐大气腐蚀钢供货技术条件的要求.     

球化组织对AISI 420型钢淬回火特性及耐蚀性能的影响

对比研究了两种AISI 420型钢球化组织的平均粒径和圆整度，并对两种钢材进行了不同淬火和回火处理工艺.然后通过硬度测试、扫描电子显微镜（SEM）和X射线衍射仪（XRD）来比较球化组织对淬回火特性的影响，同时借助动电位极化曲线测试和质量分数3.5% NaCl溶液浸泡腐蚀来分析耐蚀性能的差异.结果表明:细小弥散的球化组织在淬火时可以提高AISI 420型钢的C元素的固溶量，提高了其淬硬性，但是会提高残留奥氏体的含量；尺寸更小的退火态碳化物可以使AISI 420型钢的基体在奥氏体化过程中溶解更多的Cr元素，从而使得其在淬回火后基体Cr含量更高，减小贫Cr区产生几率，最终显示出更好的点蚀抗力；更少的大尺寸的未溶碳化物在腐蚀环境中降低了点蚀形核几率，提高了AISI 420型钢的耐蚀性能.所以在250℃回火时，AISI 420型钢耐蚀性好且硬度高，在480℃回火后，耐蚀性最差.      

Microalloyed Steels for Heat Treating Applications at Higher Process Temperatures

The potential is considered for use of microalloyed bar steels,in conjunction with thermomechanical processing,to enhance the properties of steels heat treated at higher process temperatures than have been used historically.Two examples are highlighted:microalloyed spring steels with enhanced resistance to tempering and Nb-modified gear steels for high temperature vacuum carburizing,e.g.on the order of 1050℃ versus 930℃ for a typical gas carburizing operation.In the spring steel example,the Nb+V steel results in significantly finer prior austenite grain sizes than the other steels considered,enhanced fatigue performance,and improved toughness.In the Nb-modified carburizing steel,Nb additions up to 0.1 wt pct to a Ti-modified 8620 steel,in conjunction with thermomechanical processing to control initial precipitate distributions prior to carburizing,are shown to lead to materials with improved resistance to abnormal austenitic grain growth at the higher process temperatures.Alloy content and heating rate to the carburizing temperature were shown to be important variables and suppression of abnormal grain growth was correlated with the development of a critical distribution of fine NbC precipitates,stable at the austenitizing temperature leading to improved fatigue performance in steels with fine and uniform grain structures.Opportunities for extending the results of this study to alloy design and controlled rolling in bar mills are assessed.     

Technology innovations on high quality special steel products

Because special steels are the basic materials for industrialization,a national R&D program on special steel technology for high quality products have been granted to promote the special steel production and applications since 2008.Since then,great progresses have been achieved on ferritic stainless steel sheets,heat resistance steel pipes and tubes,microalloyed forging steel bars,and mould steel forgings for hot working. The ratio of ferritic stainless steel sheets produced by TISCO and Baosteel has been promoted through technology innovations and increased 42%and 48 in 2009 respectively.439M steel sheets have been used to exhaust system,and 444 steel sheets have been applied to kitchen and architecture.The production technologies for heat resistance steel pipes and tubes(T/P92,S3043,S31042 steels) have been developed in Baosteel and Pansteel to meet the market requirements.Meanwhile,the round bloom technology has been initiated in Xingcheng Steel.The new technologies for microalloyed forging steels,low cost steel bar,and tailored steel and components,were proposed by CISRI based on the understanding of precise chemical composition and segregation control.And the applications of microalloyed forging steel bars have been promoted remarkably.The researchers have developed high quality mould steel technologies,heavy section forgings of 718 steel,high premium H13 steel blocks and large diameter mandrels used for seamless pipe rolling.The technology innovations of the program could lead to the progress of production technology in special steel sheets,pipes,bars and forgings,and meet the demands from market.For the moment,it is actually believed that there still strong requirements for the technology innovations on special steels.