薄壁耐热合金钢离心铸管涂料的研究

介绍了一种新的离心铸造用涂料的配制，测定了其有关性能。试验表明，它具有良好的工艺性能，抗热裂性能，绝热性能及发气量低等优点。可用于热模法离心铸造薄壁耐热合金钢管的生产。     

氮碳共渗钢的拉伸特性

本文对45钢氮—碳共渗不同冷却方式的拉伸特性进行了研究。试验得到一种新的锯齿状拉伸曲线和与之相对应的三区域断口特征。拉伸曲线和断口特征与冷却方式有关,并对此进行了分析。     

Cr27Ni7链节钢断裂失效的显微组织分析

借助光学显微镜、扫描电境、显微硬度计和X射线衍射仪等手段，对不同服役周期的链节进行了显微组织分析，确定了Cr27Ni7链节钢断裂失效的显微组织原因。结果显示，链节在900℃高温热循环条件下长期使用，其显微组织中的碳化物类型发生转变以及晶界弱化，显著地降低了Cr27Ni7链节钢的冲击韧性和拉伸塑性，即使没有冶金缺陷（缩松、夹杂物），也已使链节接近或达到其使用寿命。为延长使用寿命，可采用高温晶界强化和添加取代铬的使碳化物更加稳定的少量合金元素。     

STE355钢焊后显微组织中的粒贝及其对韧性的影响

研究焊接热模拟工艺参数(峰值温度Tmax和焊后冷却时间t8/5)对低碳微合金Ti—Nb钢(STE355钢)热影响区(HAZ)显微组织及冲击韧度的影响。选用干涉层腐蚀法，在光学金相显微镜下清晰显示出了显微组织中的粒贝及M—A组元。观察了Tmax和t8/5不同的热模拟试样中粒贝及M—A组元的形态及分布特征，研究了不同Tmax及t8/5参数对显微组织及冲击韧度的影响，并用电子显微镜进行了观察和验证。结果表明，热模拟峰值温度的升高，或冷却趋缓，都使显微组织变粗、韧性降低。沿晶铁素体和晶内铁素体片的长大、增厚，粒贝中块状M—A岛的长大，都对韧性的改善不利。     

The Recovery of Elastic Properties at 35 °C in TRIP 700 Steel Following Deformation

The influence of plastic deformation on the elastic properties that determine the magnitude of springback following forming was investigated using dynamic modulus analysis. For this study, the elastic modulus of TRIP 700 steel was measured continuously at 35 °C and a loading frequency of 1.0 Hz for 1000 min following deformation by cold rolling to varying levels up to 27%. The elastic modulus increased at an exponentially decaying rate during these experiments and with a magnitude that increased with pre-strain. These observations are consistent with the hypothesis that deformation creates microstructural defects that contribute compliance when the stress state changes and that these defects are removed by annealing at this low temperature. This article was presented at Materials Science & Technology 2006, Innovations in Metal Forming symposium held in Cincinnati, OH, October 15-19, 2006.     

Surface physico-chemistry study of an austenitic stainless steel: Effect of simple cold rolling treatment on surface contamination

The surface physico-chemistry properties of stainless steel and the effects of a cold rolling treatment were investigated. X-ray photoelectron spectroscopy (XPS) analyses were carried out on rolled surfaces at different rates. Thus, by characterizing passive film chemistry and contamination layer, the modifications due to this treatment were quantified, in particular an increase of the ratio (Fe/Cr)_oxide is evidenced with the level of the cold rolling treatment. Moreover, based on an angle resolved analysis, a new model where the contamination layer is represented as isolated parts was developed in order to describe the geometry of this carbon contamination. XPS experiments show an iron enrichment of the passive film during the cold rolling treatment, which seems to be explained by a surface heating during the mechanical treatment. Therefore, the new island model puts in evidence the effects of ageing time and surface condition on the geometry of carbon contamination. Hence, cold rolling increases the thickness and the recovery of carbon contamination on the stainless steel surface.     

CM690锚链钢开裂原因分析

对CM690锚链钢进行裂纹形貌、金相组织、夹杂物及低倍的检验和分析,结果表明,锚链的开裂是由于连铸坯中的细小裂纹及热处理工艺控制不当造成的.     

316不锈钢藕状多孔结构的选区激光烧结制备

研究了一种新型的制备金属藕状多孔结构技术——选区激光烧结，着重说明该技术的基本原理和工艺过程，并利用此制备技术成功获得了藕状多孔试样。利用SEM分析了316不锈钢藕状多孔试样的微观孔隙特征，并测定其孔隙率，结果表明其孔径大小分布均匀（2-4μm），平均孔隙率约为60％，孔隙贯通性良好；初步探讨了选区激光烧结制备316不锈钢藕状多孔结构的成形机制。     

The influence of sulphate-reducing bacteria biofilm on the corrosion of stainless steel AISI 316

This work investigates microbially-influenced corrosion (MIC) of stainless steel AISI 316 by two sulphate-reducing bacteria, Desulfovibrio desulfuricans and a local marine isolate. The biofilm and pit morphology that developed with time were analyzed using atomic force microscopy (AFM). Electrochemical impedance spectroscopy (EIS) results were interpreted with an equivalent circuit to model the physicoelectric characteristics of the electrode/biofilm/solution interface. D. desulfuricans formed one biofilm layer on the metal surface, while the marine isolate formed two layers: a biofilm layer and a ferrous sulfide deposit layer. AFM images corroborated results from the EIS modeling which showed biofilm attachment and subsequent detachment over time.     

Nucleation of corrosion pits in Ringer’s solution containing bovine serum

The effects of the presence of bovine serum on the nucleation of corrosion pits on 316L stainless steel and commercially pure titanium in Ringer’s physiological solution at 37 °C are presented. The experiments involved measurement of current transients generated on microelectrodes under potentiostatic control below the pitting potential. Results show that the presence of the organic components of the serum stimulates the nucleation of pits on 316L stainless steel. A similar but smaller effect is shown for commercially pure titanium.