浅谈奥贝球铁及其应用

介绍了奥贝球铁的发展历程和使用价值,阐述了化学成分对奥贝球铁力学性能的影响,分析了奥贝球铁等温淬火热处理规范及工艺过程,对具有高强度、高韧性的奥贝球铁材料的工业应用情况作了介绍,并提出了一些促进奥贝球铁产业化发展的建议.     

奥贝球铁的热稳定性

测定了奥贝球铁在连续缓慢和加热条件下的回火曲线，分析讨论了其回火过程中的变化特点，研究了合金元素Ｎｉ不同加入量，等温淬火工艺对奥贝球铁热稳定性的影响及其影响机制。结果表明，在贝氏体第一阶段转变结束时，奥贝球铁表现出较好的热稳定性，合金元素Ｎｉ加入量的增加使奥贝球铁的热稳定必降低，奥氏体化温度和等温淬火温度提高可使奥贝球铁的稳定性提高。     

铜钼合金奥贝球铁力学性能的稳定性

研究了铜钼合金奥贝球铁力学性能的稳定性。结果表明：在95％的概率下，所研制的铜钼合金奥贝球铁达到了国外同类材料的力学性能水平；铸造缺陷、石墨形态和基体组织对奥贝球铁力学性能的稳定性产生显著影响，并相应地提出了质量控制的基本原则。     

等温淬火温度和时间对奥贝球铁组织性能的影响

本文通过工艺试验,介绍了奥贝球铁在等温淬火的不同温度下的变化情况及对其切削性能的影响,给出了最佳等温淬火温度和时间。     

锰对奥贝球铁性能的影响

奥贝球铁能够实现高硬度的同时具有较高的韧性，适用于一定冲击条件下耐磨零件的工作要求。研究了高硅条件下锰对奥贝球铁性能的影响，为该材料的应用提供了试验基础。     

奥贝球铁凸轮表面激光强化的工艺研究与应用

阐述用奥贝球铁代替 2 0Cr制造内燃机车凸轮轴的激光表面强化的工艺过程 ,其中包括奥贝球铁的选择、激光工艺参数的确定、螺旋激光扫描带、四联动微机控制装置的设计等。研究表明 ,用奥贝球铁代替 2 0Cr制造凸轮轴 ,经激光表面强化后 ,能获得更均匀的硬度分布和更高的硬度值。在与常用的GCr15挺杆滚子配合使用时 ,具有更好的材料匹配性 ,能有效地减少和防止点蚀和拉伤等现象的发生     

用高锰生铁生产奥贝球铁的研究及应用

在分析在锰对奥贝球铁组织和性能的影响的基础上，研究了用高锰生铁生产奥贝球铁的方法。结果表明，采用强化孕育处理等工艺，可使含锰０．７％左右的奥由球铁具有较理想的金相组织和力学性能。     

奥贝球铁汽车齿轮的开发研究及其应用

对奥贝球铁发动机齿轮的铸造工艺进行了试验研究，并对奥贝球铁发动机齿轮的金相组织和力学性能进行了检测分析，确定了合理的铸造和热处理工艺规程，结果证明，该工艺是可行的。     

降低柴油机噪音的球铁齿轮研制成功

一种能有效降低柴油机整机噪音的“奥贝球铁齿轮”，日前在一汽无锡柴油机厂通过评审，这种球铁齿轮将代替原来的钢齿轮。 “奥贝球铁齿轮”具有优异的综合机械性能，用其制造的受力较为复杂的齿轮等零件重量轻、吸震好、噪音小，受到国内外专家的关注。一汽无锡柴油机厂从去年开始进行“奥贝球铁齿轮”代替调质钢齿轮的实验研究.实验结果表明，整机降低噪音１．９２ｄＢ。降低柴油机噪音的球铁齿轮研制成功     

奥贝球铁汽车正时齿轮应用研究

研究了用连铸球铁棒材制备奥贝球铁汽车正时齿轮的生产工艺。结果表明，用含Ｍｎ达０．７２％的球铁棒材，经合适的等温淬火处理后，能获得较理想的奥贝球组织和较高的综合力学性能。     

Low-loss austempered ductile iron gears: Experimental evaluation comparing materials and lubricants

An experimental study to evaluate the power dissipation of gears was performed.Three low-loss gear models were manufactured using standard 20° pressure angle tools. Austempered ductile iron (ADI) and 20MnCr5 carburized steel gears were tested in an FZG gear test machine using mineral, ester and polyalphaolephine (PAO)-based oils.The results compare power dissipation, the influence of different tooth flank geometries, materials and lubricants.This work concludes that conventional power-transmission gears can be replaced by these improved and more efficient low-loss models, which can be produced using common tools and that steel gears can be successfully replaced by austempered ductile iron gears.     

新型阀门电动装置蜗杆传动模糊优化设计

将模糊优化设计方法应用于电动装置的蜗杆传动设计,建立了模糊优化数学模型,并对其求解方法进行了详细的说 明,通过实例表明模糊优化设计可以使蜗杆传动更加符合客观实际,从而进一步减小电动装置的体积,提高电动装置的 效率。     

阀门电动装置蜗杆传动模糊优化设计

将模糊优化设计方法应用于电动装置的蜗杆传动设计 ,建立了模糊优化数学模型 ,并对其求解方法进行了详细的说明 ,通过实例表明模糊优化设计可以使蜗杆传动更加符合客观实际 ,从而进一步减小电动装置的体积 ,提高电动装置的效率。     

Erosion behavior of high silicon bainitic structures: I: Austempered ductile cast iron

The erosion behavior of unalloyed austempered ductile cast iron has been studied as a function of austempering time for irons austempered in the upper bainitic temperature range (370 °C). A minimum erosion rate and iron matrix hardness occurs at the end of the stage II austempering time, where the microstructure consists of bainitic ferrite and retained austenite. Experiments show that erosion induces transformation of retained austenite at early times of stage II austempering and that maximum erosion resistance correlates with maximum work hardening of the substrate during the erosion process. Scanning electron microscopy studies of the eroded surfaces and the substrate revealed that the material removal in erosion occurs because of the cutting, ploughing and flake formation mechanisms which depend upon the microstructures and their mechanical properties.     

Effect of structural features on erosion resistance of cast irons

Erosion resistance of four types of cast iron of different microstructures and graphite morphologies (viz., grey cast iron, compacted graphite iron, spheroidal graphite iron and austempered ductile iron) was evaluated in three different erosive media. Results indicate that austempered ductile iron has the highest erosion resistance in all three media, followed by spheroidal graphite iron, compacted graphite iron and grey cast iron, in that order. Graphite morphology has a significant effect on the erosion resistance of these irons in quartz-water and iron oxide-oil slurry. However, the matrix microstructure determines the erosion resistance of these irons in quartz-oil slurry. The parameter H/E (which is the ratio of the Brinell hardness number to Young's modulus of the material) has been found to be a good indicator of erosive wear in quartz-oil slurry.     

铸态奥氏体-贝氏体球墨铸铁的研究

本文较系统地研究了在不同模数下,合金加入量对铸态奥氏体-贝氏体球墨铸铁的组织和性能的影响。研究结果表明,通过合金化获得铸态奥-贝球铁是可行的。它的抗拉强度可达9×10{sup}8N/m{sup}2以上,延伸率可达3%以上。并且它具有较高的低温冲击韧性,在-40℃时,冲击韧性（V型缺口）达4.6J。常温断裂韧性可达5.4×10{sup}7N/m{sup}(3/2),经325℃回火后可再提高20%,研究表明,残余奥氏体对于机械性能有良好的作用。     

Transition temperature and fracture mode of as‐castand austempered ductile iron

The ductile to brittle transition temperature is a very important criterion that is used for selection of materials in some applications, especially in low‐temperature conditions. For that reason, in this paper transition temperature of as‐cast and austempered copper and copper–nickel alloyed ductile iron (DI) in the temperature interval from ?196 to +150°C have been investigated. The microstructures of DIs and ADIs were examined by light microscope, whereas the fractured surfaces were observed by scanning electron microscope. The ADI materials have higher impact energies compared with DIs in an as?cast condition. In addition, the transition curves for ADIs are shifted towards lower temperatures. The fracture mode of Dls is influenced by a dominantly pearlitic matrix, exhibiting mostly brittle fracture through all temperatures of testing. By contrast, with decrease of temperature, the fracture mode for ADI materials changes gradually from fully ductile to fully brittle.     

Improvement of ductile iron wear resistance through local surface reinforcement

Ductile iron (DI) or spheroidal graphite cast iron is an attractive ferrous material being widely used due to its combination of low cost and good combination of strength, toughness and fatigue endurance. However, under severe service conditions, experienced in seashore, earth-moving and mining applications the performance and reliability of DI are limited due to its poor wear resistance. Wear resistance of DI can be improved through different heat treatment and surface engineering techniques, each having some limitations and drawbacks. Recently, a new method called OPTICA has been introduced, which through local reinforcement with inserts improves wear resistance of ductile iron without compromising other properties.Results of the present investigation show that tribological properties of ductile iron can be greatly improved by local surface reinforcement. Through the formation of carbides a hard transition or functional gradient zone is formed around the inserts, which then carries the load and improves wear resistance of ductile iron, at the same time maintaining low friction. However, wear resistance of reinforced ductile iron can be improved even further, using proper austempering process. If austempered at 350 °C, wear resistance of ductile iron will become comparable or even better than reference Hadfield grade steel. In this paper reinforced or reinforcement refers to locally alloyed material in preselected zones of the casted object if not specified otherwise.     

Effects of heat treatment on the erosion behavior of austempered ductile irons

The normal-angle erosion behavior of austempered ductile irons has been studied under various heat treatment parameters, including time and temperature for both austenitization and austempering process. The results indicate that the erosion rate was in generally positively related to hardness and tensile strength, and inversely proportional to percentage elongation and mechanical energy density. Un-dissolved ferrite during austenization appears to be the most erosion resistant phase. For ADI with complete austenization, the microstructure obtained inside the process window was more erosion resistant than otherwise. At different austempering temperatures, higher temperature tends to be more erosion resistant, since more ductile austenite present in the microstructure.