ZHU Dao fei
,
ZHENG Zhong
,
GAO Xiaoqiang
钢铁研究学报(英文版)
Aiming at the limitations of the traditional mathematical model for production planning, a novel optimization model is proposed to improve the efficiency and performance for production planning in steelmaking and continuous casting (SCC) process. The optimization model combined with parallelbackward inferring algorithm and genetic algorithm is described. To analyze and evaluate the production plans, a simulation model based on cellular automata is presented. And then, the integrated system including the production plan optimization model and the simulation model is introduced to evaluate and adjust the production plan online. The test with production data in a steel plant shows that the optimization model demonstrates ability to deal with time uncertainty in production planning and to set up a conflictfree production plan, and the integrated system provides a useful tool for dynamically drawing and adjusting a production plan online. The average staying time of the production plan is about 5% shorter than that in a practical process.
关键词:
steelmaking-continuous casting;production plan optimization;genetic algorithm;cellular automata
Yongli Huang
材料科学技术(英文)
The reverse analysis provides a convenient method to determine four elastic-plastic parameters through an indentation curve such as Young's modulus E, hardness H, yield strength σy and strain hardening exponent n. In this paper, mathematical analysis on a reverse algorithm from Dao model (Dao et al., Acta Mater., 2001, 49, 3899) was carried out, which thought that only when 20≤E*/σ0:033≤26and 0.3<n≤0.5, the reverse algorithm would yield two solutions of n by dimensionless function Π2. It is shown that, however, there are also two solutions of n when 20≤E*/σ0:033≤26 and 0≤n<0.1. A unique n can be obtained by dimensionless function Π3 instead of Π2 in these two ranges. E and H can be uniquely determined by a full indentation curve, and σy can be determined if n is unique. Furthermore, sensitivity analysis on obtaining n from dimensionless function Π3 or Π22 has been made.
关键词:
Elastic-plastic properties
,
null
,
null
,
null
,
null
Yongli Huang
材料科学技术(英文)
The reverse analysis provides a convenient method to determine four elastic-plastic parameters through an indentation curve such as Young's modulus E, hardness H, yield strength σy and strain hardening exponent n. In this paper, mathematical analysis on a reverse algorithm from Dao model (Dao et al., Acta Mater., 2001, 49, 3899) was carried out, which thought that only when 20≤E*/σ0:033≤26and 0.3<n≤0.5, the reverse algorithm would yield two solutions of n by dimensionless function Π2. It is shown that, however, there are also two solutions of n when 20≤E*/σ0:033≤26 and 0≤n<0.1. A unique n can be obtained by dimensionless function Π3 instead of Π2 in these two ranges. E and H can be uniquely determined by a full indentation curve, and σy can be determined if n is unique. Furthermore, sensitivity analysis on obtaining n from dimensionless function Π3 or Π22 has been made.
关键词:
Elastic-plastic properties
,
null
,
null
,
null
,
null
Haihua LIU
金属学报(英文版)
doi:10.1016/S1006-7191(08)60120-9
A novel method was reported to measure the remnant magnetic field in Lorentz mode in a FEI Tecnai F20 transmission electron microscope equipped with a Lorentz lens. The movement of the circle Bloch line of the cross-tie wall in Permalloy is used to measure the remnant magnetic field by tilting the specimen and adjusting the objective lens current. The remnant magnetic field is estimated to be about 17 Oe, in a direction opposite to that of the objective lens magnetic field. The remnant magnetic field can be compensated by adjusting the value of the objective lens current.
关键词:
Lorentz electron microscopy
,
Lorentz lens
,
remnant magnetic field
,
Permalloy
,
cross-tie walls
王海侨
,
张永钦
,
曾繁涤
,
王晓工
,
刘德山
高分子材料科学与工程
采用Scholl反应,以硝基苯作溶剂,无水三氯化铁为催化剂,合成了系列可溶性烷氧基对称二取代的聚对苯撑(DAO-PPP),并用多种手段对其结构进行了表征,研究了聚合物的光致发光性能.实验表明,烷氧基的引入不但明显改善了PPP的溶解加工性能,而且随烷氧基侧链链长的改变,聚合物的最大紫外吸收峰、带隙Eg、光致发光(PL)最大发射峰及其发射强度都呈现规律性的变化,文中对此进行了初步的探讨.
关键词:
烷氧基二取代聚对苯撑
,
合成
,
光致发光
,
性能
刘天成
,
卢志超
,
李德仁
,
孙克
,
周少雄
,
卢燕平
功能材料
采用电沉积方法从硫酸盐体系镀液中沉积得到Fe18Ni82合金薄膜.运用扫描电子显微镜(SEM),原子力显微镜(AFM),透射电子显微镜(TEM)和X射线衍射分析(XRD)以及磁测量设备分别对薄膜的表面形貌、显微结构和磁性能进行表征和测量.同时利用万能材料试验机和显微硬度计测量了薄膜的力学性能.结果表明:电沉积制备的Fe18Ni82合金薄膜成分均匀,表面平整、光亮、致密,晶粒大小为40~50 nm.薄膜是以Ni为溶剂原子,Fe为溶质原子的置换型固溶体,只存在单一的fcc相,Fei8Ni82合金薄膜沿(111)面有较强的择优取向.镀态Fei8Ni82合金薄膜在50 Hz交流磁场下,测得其饱和磁感应强度为1.08 T,最低矫顽力为20 A/m.19 μm厚的纳米晶薄膜的断裂应力达到785MPa,显微硬度达到605Hv.
关键词:
铁镍合金
,
薄膜
,
电沉积
,
纳米结构
,
性能
邓联文
,
周亮
,
李慧敏
,
黄生祥
,
丁丽
,
周克省
材料导报
利用ZnFeO4铁氧体材料居里温度对Zn含量敏感的特点,将其作为主成分,通过Cu、Ti离子掺杂技术调整居里温度并提高材料的温度稳定性.采用传统氧化物工艺制备CuTiZn尖晶石铁氧体材料;采用测量起始磁导率的温变曲线间接测量居里温度的方法,获得了CuTiZn磁热铁氧体材料的居里温度.结果表明,Zn含量增加将使居里温度快速下降;材料成分为Cu.0.45Zn0.55Ti0.03Fei.97O4时居里温度为44.9℃,起始磁导率达852.5,且居里温度点磁导率的变化率达50.3/℃,该组分的CuZnTi铁氧体具有良好的自控温灵敏度,可以用作温热疗法磁热材料.
关键词:
CuTiZn铁氧体
,
居里温度
,
磁热效应
,
温热疗法
马建勋
,
严密
,
赵传礼
,
肖洪博
,
文玉华
,
杨德仁
材料科学与工程学报
doi:10.3969/j.issn.1673-2812.2005.02.023
本文研究了Sm含量,凝固速度及Nb和Zr元素的添加对Sm-Fe合金微观组织及氮化后Sm2Fei7Nx合金磁性能的影响.研究结果表明:采用真空感应炉熔炼Sm-Fe合金,当Sm的补偿量大于10wt%时,合金铸锭组织中出现大量的富Sm相,这将导致氮化后磁体磁性能的恶化;提高铸锭的冷却速度及添加Nb和Zr等元素可以有效地细化铸锭中α-Fe相的晶粒,减少均匀化退火后α-Fe相的数量,提高磁性能.
关键词:
微观组织
,
Sm2Fei7Nx
,
磁性能