Oil quenched malleable iron,the strength of an old material in a “green cast” development and a new

来源 :中国铸造 | 被引量 : 0次 | 上传用户:miclleg
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Malleable iron lost the interest and the development stopped in the turbulent seventies of tremendous developments of new technologies.The personal computer,emission spectrometer,thermal analysis,cold-box core system and automatic vertical moulding were introduced into the foundry industry.Experience shows that these new technologies do not always match up with malleable iron.Solidification and mould filling simulation programs are not always capable to handle a low carbon equivalent iron like malleable iron.Recent developments show however by using these new technologies and combined with practical experience,it is possible to increase the casting yield of malleable iron to the same level as ductile iron.The mechanical properties,especially the yield strength of malleable iron according to the standard are equivalent to those of ductile iron,however the yield strength of oil quenched malleable iron is significantly higher than that of ductile iron.An extensive investigation is made between ductile iron,air quenched and oil quenched malleable irons based on the properties of more than 350 test bars produced under the same conditions.The results are compared with the existing international standards and discussed.Other properties like fatigue strength and response to surface treatments as induction hardening are also discussed.The costs of malleable iron are reviewed and compared with other ferro alloys.These recent developments in increasing the casting yield,the understanding of the strength,makes malleable iron competitive with ductile iron and cheaper than the first grade of ausferritic ductile iron,or steel qualities.It is possible to design lighter and save weight which is essential in the automotive industry.An example of"green cast"development for typical applications,used in automotive transmissions and engines are shown.
其他文献
本文采用30 keV的He离子辐照Hastelloy N合金,辐照温度为500°C,剂量分别为:1×1015、5×1015、1×1016 He+/cm2.利用扫描电子显微镜(SEM)研究了辐照后块体样品的表面形貌.结
Currently, for some complex plastic deformations, the analytical solution can not be obtained by using Mises yield criterion, because Mises yield criterion is n
Robot welding is an important developing direction of welding automation and intelligentization, and automatic seam tracking technology is one of principal rese
直流电源控制参数的准确度对判断电源的输出以及提高加速器更换束流的效率均有显著影响,因此进行了直流电源一致性标定的工作.本文首先介绍了兰州重离子加速器直流电源一致性
对不同的单轴压力下花岗岩氡析出量的影响进行实验探究,得到单轴压力值与花岗岩试样析出氡之间的关系,以此建立地质体处于孕震压密阶段时,氡析出量变化的实验模型。利用岩石
A series of hyperbranched poly (amine-ester)polyols were synthesized by the polycondensation of N, Ndiethylol- 3- amine-methylpropionate (prepared by Michael ad
近年来,活性炭吸附放射性氙被越来越广泛应用于核电项目的尾气处理中.活性炭对氙的动态吸附系数与其孔结构关系甚大,而相关研究却很少,因此有必要研究二者的关系,为活性炭的
在研制用于高能中性束注入器的兆瓦级强流离子源时,关键的一环是对用于产生兆瓦级离子束的加速电极的位置度进行测量和分析.以EAST-NBI强流离子源地电极模块为测量对象,通过
数字核谱仪系统中脉冲幅度提取的准确性与实时性直接影响到系统的能量分辨率与脉冲通过率.本文对高速ADC采样后的数字核信号脉冲幅度提取方法进行研究,将幅度提取方法按直接
通过堆芯围筒组件模拟件(1∶1)的动态特性试验,可以获得AP1000堆内构件堆芯围筒组件在空气中动态特性(固有频率、阻尼比和对应的振型).本试验采用多输入多输出(MIMO)试验方法