氢对不锈钢电渣堆焊层塑韧性的影响

模拟加氢反应器的工作条件（ｐ＝ １７．５ ＭＰａ，ｔ＝ ４５０ ℃）对００Ｃｒ２０Ｎｉ１０Ｎｂ 电渣堆焊层充氢。结果表明，充氢导致堆焊层断裂韧性值减小、塑韧性显著降低。在面弯试验中，堆焊层由于充氢后脆化而发生小角度开裂，其面弯断口呈脆性准解理形态，并有较多的二次裂纹；面弯产生的显微裂纹沿δ／γ相界分布。据此认为充氢首先使δ／γ相界面脆化。充氢后的堆焊层经６３０ ℃×４ ｈ 去氢处理可消除氢脆现象，使塑韧性恢复。     

Influence of Heat Treatment Temperature on Micro-structure and Property of 00Cr13Ni5Mo2 Su-permartensitic Stainless Steel

The microstructural evolution and mechanical property of 00Cr13Ni5Mo2supermartensitic stainless steel(SMSS)subjected to different heat treatments were investigated.Room tensile tests,hardness tests,scanning electron microscopy,transmission electron microscopy and X-ray diffraction were conducted on the heat-treated steels.It is found that the microstructure of the heat-treated steel is composed of tempered lath martensite,retained austenite andδ-ferrite.The austenitizing temperature and tempering temperature have a significant effect on the microstructural changes,which leads to the complex variations of mechanical properties.The fine tempered lath martensite and more dispersed reversed austenite in the microstructure facilitate improving the comprehensive mechanical properties of the studied steel.The optimal heat treatment process of 00Cr13Ni5Mo2SMSS is obtained by austenitizing at 1 000℃for 0.5h+air cooling followed by tempering at 630℃for 2h+air cooling,where the excellent combination of tensile strength,elongation and hardness can be achieved.     

Influence of Tempering Process on Mechanical Properties of 00Cr13Ni4Mo Supermartensitic Stainless Steel

To investigate the influence of tempering process on microstructural evolutions and mechanical properties of 00Cr13Ni4Mo supermartensitic stainless steel(SMSS),specimens were tempered in the temperature range of 520-720 ℃ for 3 h followed by air cooling and an optimized tempering temperature was chosen to prolong holding time from 3 to 12 h.After heat treatments,microstructure examination was conducted by scanning electron microscope,X-ray diffraction examinations,hardness measurements and tensile tests.The results revealed that the superior mechanical properties were achieved by quenching at 1040 ℃ for 1 h+water cooling and tempering at 600 ℃ for 3 h+air cooling.Increasing isothermal tempering time could improve the toughness notably.It was believed that the property was correlated with the microstructure of tempered lath martensite and retained austenite.More retained austenite content is beneficial to the higher toughness of the SMSS.     

不锈钢薄板的应用及焊接

通过对不锈钢薄板在常压容器产品中的应用,对焊接、腐蚀性能的研究,介绍不锈钢薄板的焊接技术及其特点,并期待其推广应用。     

冷拔变形(F+M)型双相钢的氢脆

实验采用阴极电解预充氢试样拉伸的方法,研究了冷拔变形05Si2铁素体-马氏体型双相钢的氢脆敏感性及断裂行为。发现双相钢氢脆敏感性随着冷拔变形量的增大出现一峰值,以及氢致铁素体基体的脆化现象。     

超级高氮奥氏体不锈钢的耐腐蚀性能及氮的影响

用电化学测试、化学浸泡等方法研究了超级奥氏体不锈钢00Cr24Ni22Mo7Mn3CuN(654SMO)的耐点腐蚀和耐缝隙腐蚀的性能。通过改变氮含量,研究了氮对奥氏体不锈钢的耐点腐蚀和耐缝隙腐蚀性能的影响,结果表明,氮和适量的铬、钼结合,能显提高奥氏体不锈钢的耐点腐蚀和缝隙腐蚀的能力,并且随着氮含量的增国,砥体不锈钢的耐点腐蚀和耐缝隙腐蚀的能力也增强,对比实验表明,超级奥氏体不锈钢在耐点腐蚀,缝隙腐蚀等局部腐蚀性能方面可以和镍基合金C－276媲美,甚至优于镍基合金。     

Phase Transformation and Its Effects on Mechanical Properties and Pitting Corrosion Resistance of 2205 Duplex Stainless Steel

The effects of phase transformation on mechanical properties and pitting corrosion of 2205 duplex stainless steel were investigated. The amount of σ phase in the test specimen varied up to a maximum of 6% by thermal treatment at 850 ℃ for up to 60 min. The results showed that σ phase markedly increased the hardness and decreased the impact toughness of the test steel. But the increasing tendency of the ultimate tensile strength and the yield strength was not obvious, while the total elongation abruptly decreased with the aging time from 5 to 60 min. SEM impact microfractograph analysis revealed that the types of impact fracture changed from ductile mode to transcrystalline mode when the specimens were aged for 5-60 min. Furthermore, the extent of pitting potential reducing was found to be strongly temperature dependent, more pronounced at the higher temperature. During the incubation period of σ phase nucleation, the pitting corrosion test temperature and the aging time had collaborative effects on evidently displacing the pitting potential towards less noble values. After 15 min, the higher temperature contributed more to decreasing the pitting potential than the aging time.     

铜、硫元素对4Cr13不锈钢切削性能及耐腐蚀性能的影响

 利用车削试验研究了铜、硫元素对4Cr13不锈钢切削性能的影响,并用浸泡试验和极化曲线研究了铜、硫元素对4Cr13钢耐腐蚀性能的影响。研究结果表明：铜、硫元素均能提高4Cr13钢的切削性能,含铜4Cr13钢的切削性能达到了含硫4Cr13钢的切削水平。另外,铜元素还可提高4Cr13钢的耐腐蚀性能,而硫却致使4Cr13钢的耐腐蚀性能下降。     

Hydrogen Softening in the Thin Plate of Microcrystalline 316L Stainless Steel

The thin‐plate specimen of 316L austenite stainless steel was charged with hydrogen using a cathodic charging technique. Despite the short diffusion distance of hydrogen predicted by the diffusion‐controlled model for a semi‐infinite sheet, the Vickers hardness measurements revealed the full effect of hydrogen in the center of the cross‐sections of thin‐plate specimens as well as in the vicinity of the outer surfaces, which appears to be due to the short‐circuit diffusion mechanism along the grain boundaries. The room‐temperature tensile properties of both undeformed and deformed (20, 40%) samples were examined and compared. Hydrogen softening was apparent in both types of samples. For example, the 40% deformed sample showed an approximately 17 and 7% lower yield and tensile strength, respectively, after H charging at a strain rate of 2 × 10^?4 s^?1 with a concomitant decrease in ductility compared to that without H.     

Pitting Corrosion Behavior of Stainless Steel 304 in Carbon Dioxide Environments

The pitting corrosion behavior of stainless steel (SS) 304 in aqueous CO2-H2S-CI-environment was investigated by potentiodynamic cyclic anodic polarization and electron probemicroanalysis (EPMA). The experimental results show that the pitting corrosion susceptivityof SS 304 increases with the increase of temperature. Chlorine ion is the prerequisite for pittingcorrosion of SS 304 in H2S-CO2 environments. There is a linear relatiotxship between the pittingcorrosion potential (Eb-100) and chlorine ion concentration, and Eb-00 becomes noble with in-creasing pH value of the solution with or without H2S. pH value has little effect on the protec-tion potential with the presence of Hz S. H2S increases strongly the pitting corrosion susceptivi-ty and deteriorates the pitting corrosion resistance of SS 304 in CO2 environments. The obser-vations by EPMA show that SS 304 in CO2-saturated NaCI solution (3%) with H2S sufferspitting corrosion accompanied with intergranular corrosion.     

Effect of Morphology for Novel Bainite/Martensite Dual-Phase High Strength Steel on Its Hydrogen Embrittlement Susceptibility

It is very imperative to study the novel highstrength materials with high purity,high uniformityand refined grain,for improving the utilization rateand quality of materials.However,improving thestrength will reduce the resistance of materials tohydrogen embrittlement. For example,in lastcentury,some hydrogen embrittlements in thelanding gear of plane were reported[1] . When yieldstrength exceeds 1380 MPa,high strength steelsbeing used now exhibit strong susceptibility tohydrogen embrittlement…     

Effect of Chloride on Semiconducting Properties of Passive Films Formed on Supermartensitic Stainless Steel in NaHCO3 Solution

 The effects of chloride ion on the electrochemical behavior and the semiconducting properties of the passive film on supermartensitic stainless steel in 0. 5 mol/L NaHCO3 solution were investigated using potentiodynamic polarization, the potentiostatic current transients and Mott-Schottky analysis. The results indicated that chloride ion narrowed passivation region and improved pitting susceptibility. The steady state current densities were independent of film-formed potentials, which was in good agreement with the assumption of the point defect model (PDM). The capacitance results showed the fact that the passive films had a multilayer character. The defect density decreased with increasing passive film formation potential. The chloride ion induced changes of the acceptor densities and donor densities of the passive films.     

不锈钢在高温高压釜乙酸溶液中耐腐蚀性能研究

在试验室中模拟不锈钢所处的高温高压生产环境,对两种牌号不锈钢在同种乙酸介质中的耐腐蚀性能进行对比实验研究,并且对同种不锈钢试样在不同方法制备的乙酸介质中的耐腐蚀性能进行对比研究。试验结果显示,送样316L不锈钢的耐腐蚀性能较00Cr17Ni14Mo2不锈钢的耐腐蚀性能差;316L不锈钢在乙醇制乙酸中的耐腐蚀性能低于在乙烯制乙酸中的耐腐蚀性能。上述试验为某化工厂生产设备的选材以及生产介质的选择提供了相应依据和参考。     

节镍型不锈钢点状腐蚀缺陷分析及改进

采用SEM、EDS及电化学测试系统等手段,对节镍型不锈钢板表面腐蚀缺陷可能涉及的因素进行分析排查,从而制定了一系列的改进措施。改进后能够有效地抑制腐蚀的发生,保证了产品的表面质量。     

含稀土元素镧的节镍铬锰氮不锈钢耐蚀性

 以加入不同含量稀土元素镧的节镍铬锰氮不锈钢为对象,采用交流阻抗和极化曲线分析技术,对节镍铬锰氮不锈钢在周浸腐蚀环境下的电化学行为进行了研究。通过试验结果分析得出：加入质量分数为0～0.014%镧元素,随着镧含量增加,基体的电极电位提高;在体积分数3.5%NaCl溶液中模拟海洋大气腐蚀的48天内,节镍铬锰氮不锈钢的耐蚀性随稀土镧含量增加,耐蚀性先增加后减小,含稀土镧质量分数为0.004 9%的节镍铬锰氮不锈钢的耐蚀性最好。     

1Cr13不锈钢的土壤腐蚀行为

通过在酸性、中性及碱性土壤中埋设试件的方法,研究了１Ｃｒ１３不锈钢分别经过１年、３年、５年这三种试验周期后的腐蚀行为为特征。结果表明,１ｃｒ１３不锈钢在酸性及中性土壤中腐蚀轻微,在高盐碱必训腐蚀严重,而且以点蚀为主,土壤中Ｃｌ＾－及ＳＯ４＾２－是影响１Ｃｒ１３不锈钢腐蚀行为的最主要因素,随土壤中Ｃｌ＾－及ＳＯ４＾２－增多,１Ｃｒ１３不锈钢的腐蚀失重近似线性增大。