ZL301铸造铝合金硬质阳极氧化工艺研究

采用自制的电源设备和氧化装置对铸造铝合金ZL301在4种不同电解液中的硬质阳极氧化进行了研究.探讨了氧化膜层厚度与硬度、膜的生成电压的关系,得到ZL301脉冲阳极氧化最佳工艺方案.采用该工艺方案,阳极氧化过程中膜的生成电压较其他3种方案低,膜层光滑且致密.膜层厚度大于60μm,平均硬度HV≥300.     

Corrosion and mechanical properties of duplex-treated 301 stainless steel

Plasma nitriding is a widely used technique for increasing the surface hardness of stainless steels, and consequently, for improving their tribological properties. It is also used to create an interface between soft stainless steel substrates and hard coatings to improve adhesion. This paper reports on the mechanical and corrosion properties of AISI301 stainless steel (SS) after a duplex treatment consisting of plasma nitriding followed by deposition of Cr bond coat and CrSiN top layer by magnetron sputtering. Mechanical properties of the deposited films, such as hardness (H) and reduced Young's modulus (E_r), were measured using depth-sensing indentation. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were carried out to evaluate resistance to localized and to general corrosion, respectively. The corrosion behavior has been correlated with the microstructure and composition of the surface layers, determined by complementary characterization techniques, including XRD, SEM, and EDS. The CrSiN layers exhibited an H value of 24 GPa, whereas the nitrided layer was shown to present a gradual increase of H from 5 GPa (in the nitrogen-free SS matrix) to almost 14 GPa at the surface. The electrochemical measurements showed that the nitriding temperature is a critical parameter for defining the corrosion properties of the duplex-treated SS. At a relatively high temperature (723 K), the nitrided layer exhibited poor corrosion resistance due to the precipitation of chromium nitride compounds and the depletion of Cr in the iron matrix. This, in turn, leads to poor corrosion performance of the duplex-treated SS since pores and defects in the CrSiN film were potential sites for pitting. At relatively low nitriding temperature (573 K), the nitrided interface exhibited excellent corrosion resistance due to the formation of a compound-free diffusion layer. This is found to favor passivation of the material at the electrode/electrolyte interface of the duplex-treated SS.     

牙哈301井油管腐蚀原因分析

对牙哈301井油管腐蚀原因进行了调查研究,对油管腐蚀形貌和分布规律进行了分析,对油管材质进行了试验.通过调查研究和试验分析,认为油管为二氧化碳腐蚀,腐蚀介质来源于天然气中的二氧化碳和凝析水,腐蚀严重程度和分布规律与油管结构和井深位置有关.     

301L不锈钢的塑性变形特征研究

研究了不同压下率下(0%、9%、14%、22%和40%)301L不锈钢锻造态与固溶态的组织形变以及硬度变化特征。研究表明,锻造态奥氏体组织内存在孪晶,且晶粒较固溶态细小。固溶态301L不锈钢的硬度略低于锻造态,两者的硬度变化曲线与对应的加工硬化曲线具有相似性。经过塑性变形后两种状态下的301L不锈钢均出现了明显的加工硬化现象,随变形量的增加硬度不断提高,固溶态的加工硬化率更高,且比锻造态成形性更好,更有利于后续塑性加工;随着压下率的增加,α'马氏体不断增多,位错密度不断增高,晶粒不断碎化。     

SUS301L不锈钢电阻点焊工艺研究

研究了SUS301L不锈钢电阻点焊的工艺。结果表明:选用中等偏硬一些的焊接规范,可以获得较理想的点焊接头,接头的外观、平滑度及熔核尺寸和力学性能满足了相关标准的要求;待焊表面涂抹专用密封胶后,可形成结合线伸入缺陷,但对接头组织和力学性能影响不大。     

Adsorption of platinum(IV) onto D301R resin

Pt(IV) was quantitatively adsorbed by D301R resin in the medium of pH = 3.47. The statically saturated adsorption capacity is 410 mg/g. Pt(IV) adsorbed on D301R resin can be eluted by 1.0-2.0 mol/L NaOH. The rate constant is k₂₉₈ = 5.43 × 10⁻⁵S⁻¹. The adsorption of Pt(IV) on D301R resin obeys the Freundlich isotherm. The adsorption parameters of thermodynamics are as follows: enthalpy change ΔH = 4.37 kJ/mol, Gibbs free energy change ΔG = −5.39 kJ/mol, and entropy change ΔS = 32.76 J/(mol·K). The apparent activation energy is E_a = 22.5 kJ/mol. The coordination molar ratio of the functional group of D301R resin to Pt(IV) is 2:1.     

SUS301L不锈钢电阻点焊工艺研究

研究了SUS301L不锈钢电阻点焊的工艺。结果表明：选用中等偏硬一些的焊接规范。可以获得较理想的点焊接头，接头的外观、平滑度及熔核尺寸和力学性能满足了相关标准的要求；待焊表面涂抹专用密封胶后．可形成结合线伸入缺陷，但对接头组织和力学性能影响不大。     

Technical note Weight loss investigation of alternating voltage corrosion of 301, 304, and 316 stainless steels in boiling NaCI solution

Abstract

Alternating voltage corrosion of types 301, 304, and 316 stainless steels in an aqueous boiling NaCl solution under continuous reflux was investigated through weight loss measurements as a function of time. Specimens of each type of stainless steel were used as electrodes to heat the solution by the Joule effect using pure outlet alternating voltage modulation (127 V, 60 Hz). Pitting corrosion was observed in all cases, but it was severe for 304 and less marked for 301. This led to average percentage weight losses, after 1500 h of experiment, of up to 30%, 21%, and 16% for the 304, 316, and 301 steels respectively. The enhanced pitting corrosion of the 304 steel agrees with results previously reported in the literature by other authors.     

基于OMRON NJ301网络通信的监控系统设计

介绍一种基于OMRON FINS协议和NJ301 Ethercat网络的流水线实时监控系统,介绍该控制系统软件及硬件的设计方法。基于FINS协议,通过VB2008和SQL Server2008数据库实现数据处理和生产管理。实际应用表明:该系统能稳定有效地对流水线设备实现实时监测和控制。     

不锈钢SUS 301L激光填丝搭接焊工艺

以接头形式0.6+2mm的不锈钢SUS 301L为对象,研究激光填丝焊激光功率、焊接速度、送丝速度3个主要工艺参数对焊缝成形、接头截面形貌及连接强度的影响规律。结果表明,随着激光功率的增加,焊缝熔深和熔宽增大,余高减小;随着焊接速度的增加,焊缝熔深、熔宽、余高均减小;随着送丝速度的增加,焊缝熔深和熔宽减小,余高增大。接头的最大拉力为14.43 k N,断裂在上层薄板母材中,焊缝强度大于母材。     

Pitting and Intergranular Corrosion Resistance of AISI Type 301LN Stainless Steels

The pitting and intergranular corrosion (IGC) resistance of AISI type 301LN stainless steels were evaluated using ASTM methods, anodic polarization, and electrochemical impedance techniques. The IGC results indicated that the microstructure of the samples after sensitization heat treatment at 675 °C for 1 h shows step or dual structure for both imported and indigenous materials indicating insignificant Cr₂₃C₆ precipitation. The results of immersion tests in boiling 6% copper sulfate + 16% sulfuric acid + copper solution for 24 h followed by the bend test (ASTM A262 Practice-E method) indicated no crack formation in any of the tested specimens. Pitting corrosion resistance carried out in 6% FeCl₃ solution at different temperatures of 22 ± 2 and 50 ± 2 °C (ASTM G 48) up to the period of 72 h revealed pitting corrosion attack in all the investigated alloys. The potentiodynamic anodic polarization results in 0.5 M NaCl revealed variation in passive current density and pitting potential depending on the alloy chemistry and metallurgical condition. The passive film properties studied by electrochemical impedance spectroscopy (EIS) correlated well with the polarization results. The x-ray diffraction (XRD) results revealed the presence of austenite (γ) and martensite (α′) phases depending on the material condition. The suitability of three indigenously developed AISI type 301LN stainless steels were compared with imported type 301LN stainless steel and the results are highlighted in this article.     

冷轧301L奥氏体不锈钢的变形和应变硬化行为

研究了SUS301L和CN301L奥氏体不锈钢HT(high tensile,4/4H)和DLT(deadline tensile,1/4H)两个硬化等级冷轧板材的变形和应变硬化行为及其应变诱发α′马氏体转变.所有301L冷轧板拉伸试样近断口处都发生了85%以上的马氏体相变,轧制变形量增加,室温拉伸应变诱发马氏体转变开始的应变减小,但未增加马氏体转变饱和值.CN301L中C和N的含量高于相同硬化等级的SUS301L,导致它们变形和硬化行为不同.C和N的含量较高,对γ相和α′相的固溶强化效果增强,冷轧奥氏体不锈钢无需发生大量马氏体转变就能达到要求的高屈服强度,保证冷轧板材具有较好的塑性和一定的成型能力;此外,形成的应变诱发马氏体中,C和N的固溶度大,硬化效果增强,流变应力上升快,抗拉强度高;C和N含量较高,还增加奥氏体的稳定性,将拉伸过程中应变诱发马氏体转变推迟到较高应变发生,延长应变硬化行为的第二阶段,增强相变增塑效应.     

退火时间对冷轧亚稳态301L奥氏体不锈钢织构的影响

利用电子背散射衍射(EBSD)和X射线衍射(XRD)技术,研究在800℃退火时,不同退火时间对亚稳态奥氏体不锈钢301L织构的影响.结果表明,冷轧退火后,亚稳态奥氏体不锈钢301L织构强度明显减弱,奥氏体相织构主要由Brass{110} <112>,Goss{110} <001>和Copper{112} <111>、{225} <554>组成,并且随着退火时间的增加,Brass织构强度明显降低;同时对再结晶织构的形成机制的讨论认为,亚稳态奥氏体不锈钢301L的再结晶被“定向形核”过程所控制.     

SUS 301L不锈钢冷金属过渡焊搭接接头焊接工艺、微观组织及力学性能

随着我国轨道交通行业的飞速发展,车体减重对于节省能源有着重大意义。利用CMT冷金属过渡焊接技术对4—0.8 mm SUS301L-MT不锈钢搭接接头进行工艺研究,获取最优工艺参数;同时,观察焊接接头的宏观形貌、微观组织,测量其力学性能及变形。结果表明,在最优工艺参数下,焊缝成形美观,无明显缺陷,焊缝区组织主要为奥氏体柱状晶和枝晶状铁素体;焊接接头最大拉伸剪切力达到22 234.42 N,硬度测试最小值均出现在焊缝区;此外,焊后试板呈现波浪变形,最大Z方向变形量出现在试板边缘。     

SUS301L不锈钢冷金属过渡焊接接头焊接工艺、微观组织及力学性能

随着我国轨道交通行业的飞速发展,车体减重对于节省能源意义重大.采用CMT冷金属过渡焊接技术对4-0.8 mm SUS301L-MT不锈钢搭接接头进行了工艺研究,获得最优工艺参数;同时,对焊接接头进行了宏观形貌、微观组织观察、力学性能以及变形测量.结果表明,在最优工艺参数下,焊缝成形美观,无明显缺陷,焊缝区组织主要为奥氏体柱状晶和枝晶状铁素体;焊接接头拉伸剪切最大力达到了22 234.42 N,硬度测试最小值均出现在焊缝区;焊后试板呈现波浪变形,最大Z方向变形量出现在试板边缘.     

具有梯度结构表层301不锈钢的压缩性能

利用表面机械研磨处理技术,在301奥氏体不锈钢中得到晶粒尺度呈梯度分布的变形表层,进行了压缩试验和微观组织观察.结果表明,变形表层中晶粒可细化至100 nm.相比原始态的屈服强度236 MPa,具有变形梯度表层后屈服强度增加到436 MPa,变形后的加工硬化指数为0.31,经400和700 ℃的退火后分别增加到0.32和0.35.另外,随着应变速率的增加,流变应力增大而加工硬化能力降低.     

配分工艺对301奥氏体不锈钢组织和力学性能的影响

拟以淬火-配分的新型热处理工艺替代冷变形加工硬化工艺,进而提高亚稳态奥氏体不锈钢的力学性能。以301不锈钢为研究对象,采用光学显微镜、扫描电镜、X射线衍射仪、铁素体测量仪、万能试验机及显微硬度计等表征手段,分析了不同配分热处理制度对301不锈钢微观组织及力学性能的影响。结果表明:301亚稳态奥氏体不锈钢经不同淬火-配分工艺热处理后,其显微组织主要由板条状马氏体、奥氏体以及微量碳化物组成;其力学性能对配分温度不够敏感,但随配分时间的延长会不断优化。在450 ℃配分30 min后,301奥氏体不锈钢的综合力学性能达到最优,其屈服强度、抗拉强度、伸长率及硬度分别为432.37 MPa、1212 MPa、44.28%及193.16 HV0.2。     

D301树脂吸附钼蓝的热力学与动力学(英文)

通过静态吸附实验,研究D301树脂对钼蓝的吸附热力学和动力学。结果表明:D301对钼蓝的吸附行为符合Freundlich等温方程;在不同温度下,D301吸附钼蓝的吸附焓变ΔH和吸附熵变ΔS均为正值,而吸附自由能变ΔG为负值,表明吸附是一个自发的、吸热过程,升温有利于吸附。动力学研究表明,此吸附过程符合双驱动模型,吸附过程主要受粒内扩散步骤控制,经拟合获得动力学总方程。     

冷轧工艺对301L不锈钢组织及性能的影响

对1.5 mm厚的301L不锈钢板材进行多道次冷轧试验,得到压下率分别为20%,30%,40%的板材;通过对冷轧板材的拉伸试验、金相分析、SEM分析、XRD衍射分析及硬度测试,研究冷轧压下率对301L不锈钢组织及性能的影响规律。研究表明,随着冷轧压下率的增大,301L不锈钢中的应变诱发马氏体会逐渐增多,材料的屈服强度由789 MPa提高至1260 MPa,抗拉强度由977 MPa提高至1317 MPa,显微硬度则提高了120 HV;材料出现晶粒碎化现象,产生细晶强化;同时,由于301L不锈钢中的马氏体相变,20%压下率的301L不锈钢拉伸应变硬化指数要高于30%压下率的301L不锈钢。     

控轧工艺对301奥氏体不锈钢组织及性能的影响

对某厂生产的0.99 mm厚301不锈钢薄板进行冷轧试验,进行了室温拉伸试验、维氏硬度测量、金相组织观察以及X衍射分析。结果表明,在冷轧时形变诱导马氏体相变造成了301不锈钢硬度及强度的增大,且这种增大会随着变形量的增加而增大。