金相分析在轧辊强度计算中的应用

利用金相分析对不同石墨形态的球墨铸铁进行了强度对比。根据金相组织，初步判定了轧辊颈部扁头处发现灰斑的轧辊的芯部强度。结合轧机设计资料，对该轧辊在使用中可能出现的瞬时断裂及疲劳损坏进行了使用安全系数评估。在确保安全的前提下，将此辊装机使用，不仅为宝山钢铁股份公司成功挽回了1支轧辊(价值约14万元)，同时也为今后此类问题的解决，乃至对用理论计算方法确定有缺陷轧辊及新材质轧辊的上机安全性提供了依据。     

激光重熔球墨铸铁基陶瓷复合层的金相组织

采用金相显微镜、扫描电子显微镜等测试手段,分析了激光重熔球墨铸铁及球墨铸铁基陶瓷复合层的金相组织形貌,探讨了其形成机理。     

大断面铸态贝氏体球墨铸铁轧辊的试制

本文简述了直径大于４００ｍｍ铸态贝氏体球墨铸铁轧辊的试制过程，包括试制条件、试制工艺及试制品的性能分析。轧辊先后在６５０ｍｍ轧机上用于试轧厚８￣１３．６ｍｍ、宽２４０ｍｍ的扁钢。结果表明，其使用寿命为原铬钼球墨铸铁无限冷硬轧辊的１．５倍。     

镍铬球墨铸铁无限冷硬轧辊的研制

本文介绍该厂为线材厂粗、精轧机提供的两种镍铬球铁无限冷硬轧辊的研制过程，包括制作要求、铸造工艺参数及操作注意事项、思辊理化性能及金相组织等。试用情况表明，两种轧辊的强度高、耐磨性好、使用寿命长，达到国内同类产品的先进水平。     

金相检测图像数字化处理系统的建立及其应用

显微镜光学图像利用数码技术实现“图像信息采集→计算机处理与转存→打印输出”的连续过程,从而代替了传统的胶片照相和暗室作业。实际应用表明,即便是在放大1000倍下拍摄的数码显微图片,其组织形貌、细节、层次仍很清楚,可以满足一般金相检测对图片的要求,而且提高了金相图片制作的工作效率,节约了图片制作的成本,便于图片的交流、保存与查阅。     

焊缝金相分析系统的设计与实现

针对实际焊接工艺研究的需要,在对图像处理技术进行探索的基础上,对焊缝金相组织图像处理技术进行了研究,并在Visual C＋＋平台上开发了金相组织图像分析程序。在人机交互下,通过对金相图像进行图像预处理、图像复原、图像分割和图像识别等处理,使数码拍摄的焊缝金相组织图像可以由图像处理技术进行分割并识别,同时程序还完成了焊缝金相组织的微观结构特性参数的统计。这些参数的获得为实际焊接工艺研究提供了重要的试验参数。     

计算机在金相检验中的应用

介绍了计算机一金相显微镜系统的工作原理，同传统金相检测进行对比，论述了计算机在金相技术中的应用。     

Cr、As对水冷金属型离心铸造球墨铸铁管金相组织的影响

在实际生产的条件下,研究了Cr、As对水冷金属型离心铸造球墨铸铁管金相组织的影响。实验结果表明：为稳定获得铁素体基体的球墨铸铁管应控制Cr〈0.06%、As〈0.03%,提出了Cr、As异常时退火工艺的改进措施。     

金相图像分析技术小议

;本文从实际工作出发,提出了一些关于金相图像的制备、保存、分析处理以及管理应用的发展等技术问题的看法.     

合金元素对奥氏体-贝氏体型球墨铸铁组织和性能的影响

根据不同的合金元素对球墨铸铁基体组织的影响，将锰、钼、镍和铜的含量合理搭配，以岩棉为冷却介质，在连续冷却过程中获得了性能较好的奥氏体-贝氏体型球墨铸铁，HRC可达33～48，αk可达26～48J／cm^2。     

稀土球墨铸铁曲轴断裂的分析

运用线弹性断裂力学理论研究柴油机稀土球墨铸铁曲轴断裂强度和寿命问题。曲轴断裂的主要原因在于曲柄臂与连杆轴颈过渡圆角处存在缺陷,这个位置的缺陷在疲劳扩展达到临界状态时便导致曲轴失稳断裂。根据断裂力学理论和实验分析,提出了降低断裂率的一些途径。     

PIXE分析技术在球墨铸铁元素微分析中的应用

本文针对常规测量方法测量球铁石墨相中反球化元素含量的局限性和灵敏度低等问题,提出用电解分离工艺提取石墨相,制成无内标和含内际厚靶,用PIXE分析技术测量反球化元素和杂质元素的含量,与电子微探针相比测量下限可以提高三个量级。     

Microstructure and Mechanical Properties of Nodular Cast Iron Produced by Melted Metal Die Forging Process

 The microstructure and mechanical properties of nodular cast iron produced by the melted metal die forging process (MMDF for short) were experimentally researched. The main obtained results are: the nodular cast iron produced by this process can be machined as easy as traditional one only if holding at the remained temperature for 4 h; its strength and plasticity are obviously higher than those of traditional ones; the graphite size arrived at grade 8, and the graphite spheroidizing arrived at grade 1 or 2, but a streamline molded distribution of the graphite slightly appeared. Both of the strength and plasticity increased with the pressure when the pressure holding time was larger than its critical value. A new way to produce high properties nodular cast iron was provided.     

合金球墨铸铁基体组织对含镍球墨铸铁热疲劳性能的影响

将同炉熔炼并同时浇铸的 ,镍约 0 .7%的合金球墨铸铁楔形试块粗加工后热处理成 6种基体组织 ,再精加工成 2 0 m m× 2 0 m m圆柱试样。对试样进行了 (6 0 0± 10 )℃ (盐浴 )～ (70± 30 )℃(油 )和 (6 5 0± 10 )℃ (盐浴 )～ (2 5± 5 )℃ (水 )两种冷热循环试验 ,得到了一致的结果。发现 ,不同基体的试样其抗热疲劳性能由高到低依次为 :下贝氏体基体→ 5 6 0℃回火调质基体→ 5 80℃回火调质基体→ 6 0 0℃回火调质基体→正火片状珠光体基体→奥 -贝基体。作者结合不同基体组织的硬度和强度以及 Ac1 点以下温度范围内上述各种基体组织的热力学稳定性等因素对热疲劳性能的影响 ,阐明了导致上述试验结果的原因。     

钒钛球墨铸铁齿轮的弯曲静强度

通过试验,得到具有铁素体和贝氏体双相组织的钒钛球铁齿轮的弯曲静强度计算公式。进一步证明了,轮齿的塑性变形量与齿根应力的关系式。该试验数据,进一步充实和扩展了球铁齿轮的σ₁和k值。     

球铁铸件硬度快速判别及粗糙度引起的误差

铸件金相组织与硬度及磁性有对应关系，铸件的球光多则硬度高，磁性差，通过分析计算，用电感式传感器可以从其输出的信号快速判断球铁铸件的硬度，其判别误差与表面粗糙粒度有关。作者研制了差动式电感传感器，对实际铸件进行了测试，测试结果与理论分析计算一致。     

Centrifugal Casting of High Speed Steel/Nodular Cast Iron Compound Roll Collar

Ｈｉｇｈ ｓｐｅｅｄｓｔｅｅｌ (ＨＳＳ) ,ｉｓｃｈａｒａｃｔｅｒｉｚｅｄｂｙｅｘ ｃｅｌｌｅｎｔｈａｒｄｎｅｓｓ ,ｗｅａｒｒｅｓｉｓｔａｎｃｅ ,ａｎｄ ｇｏｏｄｒｅｄｈａｒｄｎｅｓｓ .Ｒｅｃｅｎｔｌｙ ,ＨＳＳｉｓａｐｐｌｉｅｄｔｏｍａｎｕｆａｃｔｕｒｅｈｏｔｒｏｌｌｉｎｇｒｏｌｌｓｔｏｐｒｏｄｕｃｅｓｔｒｉｐｓｏｆｇｏｏｄｓｈａｐｅａｎｄｓｍａｌｌｃｒｏｗｎｗｉｔｈｅｘｔｅｎｄｅｄｒｏｌｌｓｅｒｖｉｃｅｌｉｆｅ[1,2 ] .ＴｈｅＨＳＳｉｓａｐｐｌｉｅｄｔｏｍａｎｕｆａｃｔｕｒｅｒｏｌｌｃｏｌｌａｒｆｏｒ…     

Effects of Light and Heavy Rare Earths on Anti-Degradation of Nodular Cast Iron

The effects of rare earths with different contents on anti-degradation of Y base heavy rare earths-magnesium and cerium base light rare earths-magnesium nodular cast iron were studied. Curves of the relationship between the spheroidization grade of liguid iron treated by different nodulizers and holding time were obtained. The results show that the more the remains of the rare earth, the longer the anti-degradation time, the liquid iron was treated either by Y-Mg-Si or by Ce-Mg-Si nodulizer. When the rare earth remains are above certain quantity, the spheroidization grade starts to decline. When liquid iron treated by either Y-Mg-Si or Ce-Mg-Si nodulizer with proper remains of rare earths about 0.04% 0.06%（mass fraction）, the anti-degradation is the best, and the remains of Mg being about 0.04% -0.07% （mass fraction）. Rare earths-Mg nodulizer with moderate RE remains is better than that of Mg-Si nodulizer in anti-degradation property. However, Y-Mg-Si nodulizer with moderate remins of Re is better than Ce-Mg-Si nodulizer. Sometimes Ce-Mg- Si nodulizer can be used for the production of heavy section nodular cast iron.     

Improvements in the Characteristics of Nodular Graphite Cast Iron for Crankshafts

This study deals with spheroidal graphite cast iron metallurgy for the mass production of engine crankshafts. Pieces have been made in three different grades under industrial conditions. CCT diagrams and micrographs show that it is possible to remove the undesirable “bull's eye” ferrite from the matrix as well as to improve the mechanical properties of series parts by only altering the chemical composition. A 100% pearlitic matrix and up to a 14% increase in the tensile strength have been obtained by lowering the amount of silicon and increasing the share of pearlitizing elements such as copper and manganese without altering the cooling speed of the parts. The effect of the cooling speed on the matrix microstructure and the mechanical features has also been revealed. For an “improved” grade, the matrix is 100% pearlitic, its hardness is about 390Hv30kg for a cooling speed of around 150°C/min.