60钢盘条的试制工艺探讨

介绍了高强度60钢盘条的生产工艺流程,分析了60钢盘条试制中出现的问题：如产品质量不稳定、拉丝时断裂较多等。根据这些情况提出改进措施：改进脱硫工艺、炼钢工艺和连铸工艺等工艺措施。试制结果表明,该钢种试制工艺路线正确,产品性能达到要求,满足了用户生产钢丝的需要。     

轮胎钢丝生产断丝原因分析

扭转裂纹一直是引起轮胎钢丝生产中断丝的一个重要因素。为找出裂纹来源 ,采用 70 #钢盘条进行生产性实验 ,结果表明裂纹主要来源于原材料、酸洗、热处理及拔丝过程四个方面。     

Die-less wire drawing using polymer fluids

A die-less wire drawing process has been developed in order to investigate the performance on the reduction of wire size of polymer coating on steel wire. Previous experimental investigations have shown significant reductions in area particularly using nylon and borosiloxane on copper wire. The present investigation shows that satisfactory reductions can also be obtained using these polymers on steel wire. A smooth adhered coating of the wire was produced with the nylon; however, drawing speed limitations were observed where break up of the coatings occurred.     

用数字图像处理技术检测钢丝绳表面缺陷

介绍一种基于纹理特征提取的数字图像处理技术进行钢丝绳检测的新方法。首先利用图像处理的方法对在役钢丝绳图像进行预处理,以减小或消除噪声的影响,然后提取图像的纹理特征值——熵和平滑度,通过线性分类器来判断在役钢丝绳表面是否有断丝或锈蚀等缺陷。实验结果证明,该检测方法在实际应用中能代替人工目测,使用方便,能够满足实时要求。     

Ultrastructural effect of self-ligating bracket materials on stainless steel and superelastic NiTi wire surfaces

Frictional interactions between wires and brackets reduce the efficacy in orthodontic treatments. Self‐ligating brackets (SLBs) are now more often used due to lower frictional forces when compared with conventional‐ligating brackets. In this study, scanning electron microscopy and atomic force microscopy were used to examine the microstructural effects of stainless steel and ceramic SLBs on the surface roughness of stainless steel and superelastic NiTi wires both after in vivo clinical orthodontic treatment as well as in in vitro three‐point bending experiments. A combination of two wires—0.019 in. × 0.025 in. stainless steel wires and 0.016 in. superelastic NiTi wires—and two SLBs—both passive‐type stainless steel SLBs and active‐type ceramic SLBs—was applied for 4 months (bicuspid‐extraction) in an in vivo setting and for 1 month in an in vitro setting (200 g loads). After the SLB treatments, all wires exhibited severe scratches secondary to frictional interactions with the brackets. When used with the stainless steel SLBs (Damon 3MX®), the surfaces of 0.019 in. × 0.025 in. stainless steel (P < 0.0001) and 0.016 in. superelastic NiTi wires (P < 0.05) were significantly smoother than when used with the ceramic SLBs (Clippy‐C®). Such results suggest that orthodontic treatments with stainless steel SLBs are more effective than with ceramic SLBs. Microsc. Res. Tech. 75:1076–1083, 2012. © 2012 Wiley Periodicals, Inc.     

Defect inspection system for steel wire rods produced by hot rolling process

A vision-based inspection system has been investigated in order to improve the quality of products and processes found in various industries. In this paper, we propose a new defect detection algorithm for steel wire rods produced by the hot rolling process. Because the steel wire rods are long cylinder rods with a circular cross section, the brightness at the sides and center is inconsistent. Moreover, the various types of steel wire rods and the presence of scales affect the reflection properties of the rod surface. In order to resolve the abovementioned difficulties, the use of dynamic programming and a discrete wavelet transform are proposed. An adaptive local binarization method is used to further reduce the effects of scale. The effectiveness of the proposed method is shown by means of experiments conducted on images of steel wire rods that were obtained from an actual steel production line.     

Free abrasive wire saw machining of ceramics

Currently, many kinds of ceramics are used in advanced industrial fields due to their superior mechanical properties, such as thermal, wear, corrosion resistance, and lightweight features. Wire saw machining ceramic (Al₂O₃) was investigated by ultrasonic vibration in this study. Taguchi approach is a powerful design tool for high-quality systems. Material removal rate, wafer surface roughness, steel wire wear, kerf width, and flatness during machining ceramic were selected as quality character factors to optimize the machining parameters (swinging angle, concentration, mixed grain and direction of ultrasonic vibration) to get the larger-the-better (material removal rate) and the smaller-the-better (wafer surface roughness, steel wire wear, kerf width and flatness) machining characteristics by Taguchi method. The results indicated that wire swinging produces a higher material removal rate and good wafer surface roughness. Ultrasonic vibration improved material removal rate, without affecting the flatness under different machining conditions. Experimental results show that the optimal wire saw machining parameters based on grey relational analysis can be determined effectively and material removal rate increases from 2.972 to 3.324 mm²/min, wafer surface roughness decreases from 0.37 to 0.34 μm, steel wire wear decreases from 0.78 to 0.77 μm, kerf width decreases from 0.352 to 0.350 mm, and flatness decreases from 7.51 to 7.22 μm are observed.     

S型截面不锈钢钢丝成形工艺和模具设计

根据不锈钢材料强度高、硬化严重和S型横截面形状复杂、尺寸小的特点,确定采用两道次辊弯预成形、两道次辊模拉拔、一道次固模精拉的工艺方案,设计S型截面不锈钢钢丝五个道次成形工艺过程的轧辊孔型。此项研究成果对S型截面钢丝有重要的参考价值。     

单线切割机中的张力控制技术

介绍了用于单线切割机设备中,对于钢丝的张力闭环控制技术。为了提高切割表面的光洁度及精度,采用钢丝,并在钢丝上喷粘金刚砂进行来回切割,钢丝的张力精度直接影响切割表面的精度,因此张力的控制精度尤为重要。系统采用前后两端分别控制张力的方式,以保证整个张力的平稳。     

预应力钢绞线磁谐振应力监测试验研究

预应力钢绞线是混凝土结构的关键受力构件,其有效预应力一旦损失严重,将威胁结构安全。为了精准监测钢绞线应力状态,基于磁谐振原理和磁弹效应,提出预应力钢绞线磁谐振应力监测方法。设计了双线圈磁谐振传感器,分析了测试频率选择方法,搭建了钢绞线应力监测系统。为验证该方法的可行性,对不同设计拉力的镀锌钢绞线和涂环氧树脂钢绞线试件进行了应力监测试验。试验结果表明：不同批次的钢绞线对应的感应电压随拉力的变化趋势相似;感应电压和钢绞线应力非线性相关,三次拟合优度R~2均大于0.96,灵敏度可达0.064 79%/kN;依据拟合结果和测得感应电压计算钢绞线应力,得到在高荷载情况下钢绞线应力测试误差集中小于4%,为预应力钢绞线监测提供了新方法。     

An experimental investigation of cylindrical wire electrical discharge turning process

The cylindrical wire electrical discharge turning (CWEDT) process was developed to generate precise cylindrical forms on hard, difficult to machine materials. A precise, flexible, and corrosion-resistant submerged rotary spindle was designed and added to a conventional five-axis CNC wire electrical discharge machine (EDM) to enable the generation of free-form cylindrical geometries. The hardness and strength of the work material are no longer the dominating factors that affect the tool wear and hinder the machining process. In this study, the effect of machining parameters on surface roughness (R _a) and roundness in cylindrical CWEDT of a AISI D3 tool steel is investigated. The selection of this material was made taking into account its wide range of applications in tools, dies, and molds and in industries such as punching, tapping, reaming, and so on in cylindrical forms. Surface roughness and roundness are chosen as two of the machining performances to verify the process. In addition, power, pulse off-time, voltage, and spindle rotational speed are adopted for evaluation by full factorial design of experiments. In this case, a 2²?×?3² mixed full factorial design has been selected considering the number of factors used in the present study. The main effects of factors and interactions were considered in this paper, and regression equations were derived using response surface methodology. Finally, the surfaces of the CWEDT parts were examined using scanning electron microscopy (SEM) to identify the macro-ridges and craters on the surface. Cross sections of the EDM parts were examined using the SEM and microhardness tests to quantify the sub-surface recast layers and heat-affected zones under specific process parameters.     

Investigation into erosion rate of AISI 4340 steel during wire electrical discharge turning process

Wire electrical discharge turning (WEDT) process was developed to generate cylindrical form on any electrically conductive material applied in aerospace and automotive industry. The mechanism of metal removal in WEDT process is by means of successive spark discharge. Each spark results in the formation of crater. In the present work, a new model is proposed to predict the erosion rate of each spark for a given discharge energy. A new method is proposed to measure the crater depth from 2D roughness profile of the machined component. The proposed model is validated by conducting experiments on AISI 4340 steel and the results obtained are presented in the paper. It is observed that the results are in close proximity with the experimental values at low discharge energy. The stochastic erosion mechanism of WEDT process is analyzed using scanning electron microscope images of spark eroded wire. Using the proposed model the erosion rate can be controlled and better surface characteristic of machined surface can be achieved.     

在役钢丝绳缺陷检测方法的研究现状与展望

在役钢丝绳作为提升、运输及承载设备中的关键部件,被广泛应用于矿产、冶金、交通、建筑等国民经济各主要行业和部门。详述了目前应用于在役钢丝绳的各种无损检测方法,比较了他们的优点及不足,提出了采用超声—声发射相结合应用于钢丝绳强度检测的新原理新方法,对于提高在役钢丝绳的检测精度具有较大的理论和应用价值。     

陶瓷衬垫和药芯焊丝在焊接厚壁复合钢板中的应用

介绍了采用陶瓷衬垫,埋弧机械化焊,药芯焊丝CO2自动焊来焊接16MnR／316L不锈钢复合板的焊接工艺,解决了厚壁不锈钢复合板的焊接和热处理问题;通过检查焊缝的化学成分和力学性能等,证明了该焊接工艺的可行性,并成功应用于生产中。     

Melting rate of electrode wire in arc welding

A mathematical model is proposed for the melting rate of electrode wire during the arc welding of low-alloy steel in protective gases. The discrepancy with experimental data is no more than 4%.     

X70管线钢冷丝填充埋弧焊焊接工艺

根据X70管线钢的焊接性,提出了采用冷丝埋弧焊的工艺方法来解决焊接接头热影响区的脆化现象,通过向熔池中添加＂冷丝＂,消耗过热能量来提高焊接接头的韧性。确定X70管线钢在不同线能量下的最佳冷丝填充速度;最终得出X70管线钢冷丝埋弧焊焊接工艺参数。     

Parametric optimization for surface roughness, kerf and MRR in wire electrical discharge machining (WEDM) using Taguchi design of experiment

This paper reports the effect and optimization of eight control factors on material removal rate (MRR), surface roughness and kerf in wire electrical discharge machining (WEDM) process for tool steel D2. The experimentation is performed under different cutting conditions of wire feed velocity, dielectric pressure, pulse on-time, pulse off-time, open voltage, wire tension and servo voltage by varying the material thickness. Taguchi’s L18 orthogonal array is employed for experimental design. Analysis of variance (ANOVA) and signal-tonoise (S/N) ratio are used as statistical analyses to identify the significant control factors and to achieve optimum levels respectively. Additionally, linear regression and additive models are developed for surface roughness, kerf and material removal rate (MRR). Results of the confirmatory experiments are found to be in good agreement with those predicted. It has been found that pulse on-time is the most significant factor affecting the surface roughness, kerf and material removal rate.     

影响钢丝绳疲劳断裂的因素及提高疲劳寿命的技术措施

讨论了影响航空钢丝绳疲劳断裂的因素,通过试验研究热处理过程中钢丝完全索氏体化和不完全索氏体化时对钢丝绳的疲劳寿命影响,研究了拉拔时总压缩率、部分压缩率对钢丝绳的疲劳寿命影响,找出了能够提高疲劳寿命的技术措施。     

钢丝缠绕式模具优化设计方法研究

概述了钢丝缠绕式合成金刚石模具的工作原理,以最大预紧环承载能力为目标函数建立了优化设计模型,并以实例分析了优化模型的应用.给出了一组模具优化参数,可以作为模具设计者参考.     

基于遗传算法的拉丝机压缩比的优化设计

以LZ-9/1200拉丝机为例,运用遗传算法,以总拉拔力最小为目标,对多道次钢丝拉拔成形过程的每道次部分压缩比进行了优化设计。以Java软件为编程工具,采用面向对象的编程技术,经过选择、交叉、变异多次迭代,得到了符合要求的满意解,为实际生产提供了可行方案。