Microstructure and Properties of Mo Microalloyed Cold Rolled DP1000 Steels

  Two kinds of ultra high strength cold rolled dual phase steels have been developed by designing C Si Mn Cr and C Si Mn Cr Mo alloy systems. Tensile strength and elongation of both steels exceed 1100 MPa and 10%, respectively. The microstructures of both steels consist of massive martensite and ferrite. And the massive martensite of Mo free steel disperses in the ferrite with volume fraction of 64%. However, the massive martensite of Mo containing steel is connected or closed by small martensite islands each other, and martensite volume fraction is 69%. As to Mo free steel, the yield strength, yield ratio, and work hardening exponent n are 548 MPa, 049, and 026, respectively. As for Mo containing one, the yield strength, yield ratio, and n value are 746 MPa, 066, and 033, respectively. Besides, the ferrite of Mo free steel is deformed at the initial stage of plastic deformation. However, for Mo containing one, Mo solution strengthened ferrite and small overaged martensite islands are deformed preferentially at small strain, which causes the yield strength to reach approximately 200 MPa higher than that of Mo free steel.     

Development of Test Method for Measuring Sintering Temperature of Mould Fluxes

 Excessive sintering of mould fluxes can readily cause defects and sticker breakouts in continuously cast strands. Studying the sintering property is important to minimize problems related to sintering arising from the use of mould fluxes in continuous casting. An effective method of measuring the apparent sintering temperature has been developed in this study. The method is based on monitoring the formation of cavities caused by melting of samples. For monitoring, the differential pressure of an inert gas flow was measured through a set volume of sample (mould flux A) held in a furnace tube. The apparent sintering temperature was defined in this test to determine sintering process. The sintering properties of fluxes with various contents of carbon black were examined along with identification of mineralogical phases and the nature of the sinter for samples of mould flux A held for one hour at different temperatures. The experimental results indicated that the apparent sintering temperature (AST) was a useful parameter to assess the threat of problems related to sinter.     

A1-Zn—Cu—Si合金轴瓦材料的研究

针对现代发动机向高速重载、质轻节能、安全环保方向发展的需求,通过调整合金成分和浇铸工艺,研发出一种新型高承载能力、无铅且质轻的铝合金轴瓦材料．通过正交试验,分析了添加元素的含量对合金力学性能的影响规律,确定了备金的成分控制范围,使其性能指标可达抗拉强度σb≥180N／mm^2,屈服强度σs≥70N／mm^2,伸长率A≥22％．     

B对Al-7Si合金α相形态和力学性能的影响

研究了B对Al-7Si合金α相形态和力学性能的影响。结果表明,B对Al-7Si合金具有良好的细化效果;初生α相的形态与大小发生显著变化,树枝晶消失,转变为细小的柱状晶。当加入0.036%B时,组织最理想:形态密实、尺寸细小而均匀,同时,合金的综合力学性能得到了显著的提高,抗拉强度提高15%、延伸率提高68%、断面收缩率提高46%,弹性模量和硬度分别降低22%和9%,细化后Al-7Si合金表现出良好的强韧性。     

基于性能预报技术减少热轧带钢取样频率的探索

性能预报技术是一件具有深远影响的技术,但实现在线应用需系统考虑解决一些约束问题,目前在线应用的报道并不多见。宝钢研究了一种基于性能预报模型对现有热轧产品取样管理流程的优化方法,它通过建立带钢力学性能预报模型,将产品取样管理流程与带钢的实际生产过程相关联,对多数合格带钢实现预报替代取样,而对少数异常带钢进行有针对性地实际取样,从而达到减少取样频率的目的。基于现有生产执行系统（MES系统）的应用实践,探索出一套基于性能状态优化中间品采样频率的方案,实现了性能预报模型的大生产在线应用。该方法依托信息技术和统计技术,既实现了取样的精细化管理,又降低了运营成本。实际应用效果表明,基于性能预报模型的新取样管理方法不但没有降低可靠性,而且可以降低69%的中间品取样量;新方法在加快生产物流上效果也非常明显,可以节省23 h,这些都说明该方法是一项具有实际应用价值的技术。     

新型钢包浇注料的研制与应用

以特级高铝矾土、电熔镁砂、棕刚玉、电熔镁铝尖晶石为主要原料,研究了Secar-71水泥、硅灰、SM高效减水剂对新型钢包浇注料性能的影响。结果表明,Secar-71水泥、硅灰、SM高效减水剂外加量分别为3％、4％、0．25％时浇注料的强度高,硬化适中,流动性好。通过工业试验,钢包使用寿命最高达到118炉,平均寿命105炉,比原来的钢包浇注料（平均83炉）提高了22炉,增幅达到26．5％。现已批量投入使用,替代了原来的浇注料。     

等离子喷涂涂层的研究进展

本文介绍了等离子喷涂涂层的微观结构,力学性能,涂层表面处理及物理性能等国内外最新的研究进展。     

基于QPSO优化算法的余弦调制滤波器组设计

提出了一种新的余弦调制滤波器组设计方法,此方法以原型滤波器的阻带衰减作为目标函数,用改进型量子粒子群算法(QPSO)设计最接近满足重构条件的原型低通滤波器,然后在此基础上通过余弦调制得到分析滤波器组和综合滤波器组.实验仿真结果表明,用此方法设计的余弦调制滤波器组(CMFB)具有良好的阻带衰减特性和精确重构性能,在满足性...     

连接器电缆组件常规电性能自动检测（下）

该文在阐述连接器电缆组件导通、耐压、绝缘等常规电性能检测原理的基础上,以新研制成功的1500系列多功能检测仪为例,介绍了用多功能仪检测连接器电缆组件常规电性能的特点、主要技术参数和检测方法,以及和检测工装组成自动检测系统后的应用技术要点。     

无线光通信编码调制中交织器设计研究

交织设计是无线光比特交织编码调制通信系统抗衰落能力的一个影响因素。在构建系统模型基础上,给出了交织器优化设计的基本原则及其数学模型,对伪随机交织、S-随机交织和改进黄金分割交织的距离特性及其在弱湍流条件下的性能进行了仿真分析。结果表明,交织可有效提高编码调制的差错性能,对于给定交织方式,增加交织长度可获得更好改善,当交...