Composition design of superhigh strength maraging stainless steels using a cluster model

The composition characteristics of maraging stainless steels were studied in the present work investigation using a cluster-plus-glue-atom model. The least solubility limit of high-temperature austenite to form martensite in basic Fe–Ni–Cr corresponds to the cluster formula [NiFe12]Cr3,where NiFe12is a cuboctahedron centered by Ni and surrounded by 12 Fe atoms in FCC structure and Cr serves as glue atoms. A cluster formula [NiFe12](Cr2Ni) with surplus Ni was then determined to ensure the second phase(Ni3M) precipitation,based on which new multicomponent alloys [(Ni,Cu)16Fe192](Cr32(Ni,Mo,Ti,Nb,Al,V)16) were designed. These alloys were prepared by copper mould suction casting method,then solid-solution treated at 1273 K for 1 h followed by water-quenching,and finally aged at 783 K for 3 h. The experimental results showed that the multi-element alloying results in Ni3M precipitation on the martensite,which enhances the strengths of alloys sharply after ageing treatment. Among them,the aged [(Cu4Ni12)Fe192](Cr32(Ni8.5Mo2Ti2Nb0.5Al1V1)) alloy(Fe74.91Ni8.82Cr11.62Mo1.34Ti0.67Nb0.32Al0.19V0.36Cu1.78wt%) has higher tensile strengths with YS?1456 MPa and UTS?1494 MPa. It also exhibits good corrosion-resistance in 3.5 wt% NaCl solution.     

用密切曲率法加工自由曲面及其刀位轨迹的排列

采用中凹的盘形铣刀取代传统的球头铣刀，在每一行程中让刀具运动形成的包络面与被加工表面之间在垂直于进给方向的法截面中达到三阶密切，从而大幅度减少了走刀次数，增加了切削宽度，提高了加工效率．文中给出了边界不受限制的单张曲面的刀位及刀具轨迹的计算方法．     

气—固两相流离心风机叶型的设计方法

本文着重讨论了离心式气-固两相流风机中叶型的设计方法问题。采用控制载荷法及单相耦合和塑-脆性损失模型,分别对4种载荷的叶型进行了叶片磨损计算和分析。以磨蚀的均匀性、总的体积磨损量和气动性能作为质量评价标准,认为最小扩压度加载叶型比较好:但如果吸取其它载荷之长,组合成适当的综合加载叶型,可以在满足气动性能要求的前提下,使叶片的防磨性为之改善,从而从另一个方面证明控制载荷设计法的优越性。     

气固两相流风机的三元计算与实验结果的比较

在单相耦合模型的基础上，采用合适的粒子反弹模型和磨损模型，分析、推导、编制了三元粒子运动、碰撞的程序，并通过离心风机叶轮磨损的可视化实验，有力支持了该三元粒子程序的可靠性，为气固两相流离心风机叶轮的研制提供了行之有效的理论工具     

矿物机械活化人工神经网络-模糊专家系统的开发

针对矿物机械活化所涉及知识的复杂性,把人工神经网络（ＡＮＮ）和模糊专家系统（ＦＥＳ）有机地结合起来．用面向对象编程方法（ＯＯＰ）在Ｗｉｎｄｏｗｓ９５平台上开发出集知识库管理、数据库管理、模糊推理和人工神经网络等为一体的全３２位集成系统．可根据矿物的结构性能等参数对矿物的机械活化效果进行预测,并且集成人工神经网络可有效地抽取矿物的活化效果与矿物结构、性能之间的内在关系