压力容器内表面单层带极电渣堆焊技术

带极电渣堆焊稀释率低，效率高，是压力容器不锈耐腐层堆焊的理想方法。讨论了焊接参数，堆焊位置，磁场控制等对堆焊工艺及堆焊层性能的影响。通过实例证明了进行单层堆焊就可达到质量要求。     

特殊用途的稀土钴基永磁体

研究了具有超低温度系数、辐射取向和辐射多极取向、高电绝缘三种特殊用途的２：１７型稀土钴基永磁体及制作方法。经温度补偿的磁体剩磁平均可逆温度系数达到.５０×４５×２．５（ｍｍ）辐向环磁性能为：Ｂｒ＝１．０２Ｔ,ｉＨｃ＝１０８０ｋＡ／ｍ,（ＢＨ）ｍａｘ＝１８８ｋＪ／ｍ３。高电绝缘磁体性能为：体积电阻车＝１×１０５　－ｃｍ２／ｍ,Ｂｒ＝０．６８Ｔ,ｉＨｃ＝８００ｋＡ／ｍ,（ＢＨ）ｍａｘ＝７３．６ｋＪ／ｍ３,在５００ｋＨｚ,６６．４ｋＡ／ｍ磁场中磁化,回复剩磁不可逆损失小于１．４７％。     

不锈钢一带一剂双层电渣堆焊工艺

基于带极电渣堆焊母材稀释率低的特点，采用特制的烧结焊剂ＳＪ６０２，利用国产带极埋弧堆焊设备及国产标准焊带，研究了一带一剂双层电渣堆焊工艺及堆焊层的成分和性能，研究成果已用于生产。     

低碳钢高效带极堆焊

介绍了低碳钢的大电流带极堆焊时,焊接参数对焊缝成形和稀释率的影响,对比了高效带极堆焊和常规带极堆焊的焊层性能,证明两种工艺的焊层性能相近,高效堆焊的效率是常规堆焊的二倍。     

基于响应面法的Inconel625镍基合金GTAW堆焊工艺优化

堆焊层稀释率和厚度是影响电弧堆焊质量的重要因素,它们是由各焊接参数相互影响综合作用决定的。文中通过中心复合设计试验方案,基于响应面法建立了Inconel625镍基合金GTAW堆焊参数（焊接电流、焊接速度、送丝速度）与响应值稀释率、堆焊层厚度之间的数学模型,分析了各焊接参数对稀释率和堆焊层厚度的影响,并对堆焊参数进行了优化。结果表明,文中试验条件下送丝速度对堆焊层的厚度有着显著的影响,焊接速度和焊接电流对堆焊层厚度的影响较小;焊接电流对稀释率的影响最大,而焊接速度的影响最小;焊接电流和送丝速度的交互作用对稀释率有着重要的影响。     

9CrMoV钢堆焊1CrMo金属堆焊层性能的研究

采用1CrMo堆焊材料对9CrMoV钢进行了埋弧堆焊试验,优化了堆焊焊接工艺参数。针对不同堆焊层进行了化学成分分析,并研究了堆焊层化学成分对熔覆金属力学性能和金相组织的影响。结果表明：距离母材越远,母材对熔覆金属的稀释率越低,堆焊层合金元素含量越少,塑韧性越好;且母材与堆焊层结合性能良好,没有产生界面分离现象。上述研究成果可为超-超临界汽轮机转子轴颈堆焊技术提供理论依据和技术支持。     

D212焊条堆焊工艺对堆焊层组织性能的影响

分析了D212焊条在Q235B材料表面堆焊时堆焊工艺对其堆焊层组织性能的影响.结果表明,随着焊接线能量增加,堆焊层的稀释率加大,堆焊两层后母材的稀释作用明显降低;堆焊后去应力退火处理不会改变堆焊层组织和性能,而完全退火处理后堆焊层组织为铁素体和珠光体,堆焊层硬度显著降低.     

堆焊稀释率的影响因素和控制措施

稀释率是影响堆焊质量的重要参数，它强烈地影响着堆焊层的成分和性能。本文主要阐述了堆焊稀释率的影响因素和控制措施。     

堆焊层化学成分对9CrMoV钢熔敷金属性能影响的研究

采用1CrMo堆焊材料对9CrMoV钢进行了埋弧焊堆焊试验,优化了堆焊工艺参数.针对不同堆焊层进行了化学成分分析,并研究了堆焊层化学成分对熔敷金属力学性能和金相组织的影响.结果表明:距离母材越远,母材对熔敷金属的稀释率越小,堆焊层合金元素含量越少,塑韧性越好;母材与堆焊层结合性能良好,没有产生界面分离现象.上述研究成果可为超超临界汽轮机转子轴颈堆焊技术提供理论依据和技术支持.     

超低碳20-10型不锈钢带极电渣堆焊工艺的优化

介绍了带极电渣堆焊的原理。分析了各种工艺因素对超低碳２０－１０型不锈钢带极电渣堆焊缝成形和母材稀释率的影响。研究结果表明，焊接电流、电压、堆焊速度、带极伸出长度、焊剂层厚度、磁场控制参数、搭边量及母材试板倾角等工艺因素对焊缝成形和母材稀释率有影响。     

基于Elman网络算法的Inconel625合金堆焊稀释率的控制

文中建立了5-8-3结构的反馈Elman神经网络模型,以电弧长度、焊接电流、焊接速度、送丝速度和保护气流量为输入量,堆焊焊缝的熔宽、熔高和稀释率为输出量进行堆焊仿真计算分析.计算结果表明,Elman模型的预测结果比BP和GRNN神经网络更精确.建立了以电弧长度（X）、堆焊电流（Y）和送丝速度（Z）为空间坐标,堆焊稀释率δ等于f（X,Y,Z）为目标函数的四维图像来确定δ≤5%的堆焊工艺窗口.分别进行Elman模型仿真计算和堆焊工艺试验,得到的稀释率δ分别为2.55%和3.32%,仿真计算的稀释率的相对误差约0.8%,证实了Elman模型预测的Inconel625合金堆焊工艺窗口的可行性与可靠性.     

Optimization of weld bead geometry for stainless steel claddings deposited by FCAW

The quality of cladded components depends on the weld bead geometry, coefficients of shape of welds and dilution, which have to be controlled. Optimum range of bead parameters and dilution are required for better economy and to ensure the desired mechanical and corrosion resistant properties of the overlay. The above objectives can easily be achieved by developing mathematical equations to predict the weld bead geometry. This paper presents the development of such equations using the data obtained by conducting three factor five level factorial experiments. The experiments were conducted by depositing Type AISI 317L flux cored stainless steel wire onto IS: 2062 structural steel base plate. The results of the confirmation experiments showed that the models developed are able to predict the bead geometries and dilution with reasonable accuracy. The studies have indicated that both main and interaction effects of the process variables play a major role in determining the bead dimensions and dilution, and the effect of interaction between the process variables cannot be neglected. The process parameters were also optimized using response surface methodology (RSM) which will help the plant engineers to select and control the process variables effectively, to achieve the desired clad qualities.     

Predicting the dilution of plasma transferred arc hardfacing of stellite on carbon steel using response surface methodology

Control of dilution is important in hardfacing, where low dilution is typically desirable. At present, most fabrication industries use shielded metal are welding, gas metal arc welding, gas tungsten arc welding and submerged are welding processes for hardfacing purposes. In these processes, the percentage of the dilution level is higher, ranging between 10% and 30%. In Plasma Transferred Arc (PTA) hardfacing, a solidified metallurgical bond between the deposit and the substrate is obtained with minimum dilution (less than 10%). This paper highlights the application of response surface methodology to predict and optimize the percentage of the dilution of a cobalt-based hardfaced surface produced by the PTA process. Experiments were conducted based on a fully replicable five-factor, five-level central composite rotatable design and a mathematical model was developed using response surface methodology. Furthermore, the response surface methodology was used to optimize the process parameters that yield the lowest percentage of dilution.     

热历史对铝酸钠溶液中含铝离子之间转化的影响

为了优化拜耳法生产氧化铝的过程,有必要明晰热历史对铝酸钠溶液中含铝离子间转化的影响。通过对不同组成铝酸钠溶液经过热处理、稀释和浓缩后其红外谱图的测定,研究溶液中含铝离子间的转化规律。结果表明：升高温度和延长保温时间有助于Al2-2O（OH）6离子向880 cm-1波数处Al—OH结构四面体聚合物和Al（OH）-4转化;稀释过程中快速发生A12O（OH）2-6和Al—OH结构四面体聚合物向Al（OH）-4的转化,但稀释后溶液可发生Al（OH）-4向Al—OH结构四面体聚合物的恢复性转化;浓缩过程则发生Al（OH）-4向Al—OH结构四面体聚合物和A122O（OH）2-6的转化,且向A12O（OH）-6的转化较困难。     

宽带送粉激光熔覆稀释率的控制

在分析激光熔覆冶金过程的基础上,依据不同的计算单元,提出了单位时间、作用时间和单位长度稀释度的概念,推导出激光熔覆过程中稀释率的表达式。在利用金相法检测的基础上,结合相关的物理参数对稀释率进行了计算,系统分析了影响因素。结果表明,单位时间、作用时间和单位长度稀释率具有相同的方程,在激光参数保持恒定的条件下,稀释率均随扫描速度的增加而减小,随送粉速度的增大而变小。计算值小于几何稀释率。提出了激光熔覆熔池对流模型,并通过了试验验证。     

Ni-Al粉末直流TIG电弧堆焊层的稀释率及其控制

为了控制直流TIG电弧粉末堆焊层的稀释率,获得Ni、Al含量较高的涂层,本文研究了堆焊规范对堆焊层的形状、稀释率和化学成分的影响规律,并从降低母材温度的角度出发,考察了辅助冷源对堆焊层稀释率的影响.结果表明,随着堆焊规范的减弱,堆焊层的熔宽和熔深减小、堆高增加,堆焊层的稀释率由70%降低到32%,有利于获得低稀释率的堆焊层.在本文试验条件下采用辅助冷源对母材进行冷却,使堆焊层的堆高增大、熔深减小、稀释率降低到21%.     

Effect of dilution on the microstructure of AWS ERNiCrMo-14 alloy in overlay welding by the TIG process with cold wire feed

Dilution is an event that has a great influence on the microstructure and, consequently, in the properties of weld claddings. The present study evaluated the effect of dilution level on the microstructure of the fusion zone of alloy Inconel 686 weld claddings. The claddings were welded by the TIG cold wire feed process. The dilution was calculated from the geometric characteristics and based on chemical composition of the materials obtained by energy dispersive X-ray spectroscopy and optical emission spectroscopy. The microstructures of all claddings were composed by a γ-FCC matrix with some minor precipitates. These particles are called in the literature topologically close-packed phases (TCP). These precipitates assumed several morphological aspects, being the shapeless morphology observed in more frequency in all claddings evaluated, independent of dilution level. A phase with lamellar morphology, with growth establishing an orientation relationship with the γ-FCC matrix solidification direction, was observed only in claddings with a low dilution level. In addition, a shapeless phase with a fine precipitation aggregated was observed in claddings with a high dilution level.     

U71Mn钢表面激光熔覆Ni60-25％WC涂层工艺参数优化的研究

目的研究U71Mn钢表面激光熔覆Ni60-25%WC涂层的最佳工艺参数。方法首先通过单道单因素试验初步选取激光功率、送粉量、扫描速度和光斑直径4个工艺参数,然后进行4因素3水平的单道正交试验,以熔覆层的宽度、高度和稀释率作为判断熔覆层质量的指标,做极差分析,最后得到最优工艺参数并分析了熔覆层的显微硬度及显微组织。结果单道单因素试验及单道正交试验得到的工艺参数均为:激光功率1500 W,送粉量4 g/min,扫描速度6 mm/s,光斑直径2.2 mm。通过单道正交试验极差表分析发现,工艺参数对质量指标的影响程度不同,对熔覆层宽度的影响为扫描速度送粉量激光功率光斑直径,对熔覆层高度的影响为送粉量扫描速度光斑直径激光功率,对熔覆层稀释率的影响为送粉量光斑直径扫描速度激光功率,对比发现送粉量是熔覆层的最大影响因子。熔覆层的显微硬度最高可达到1170HV,是基体的3.7倍。结论在U71Mn钢表面激光熔覆Ni60-25%WC涂层,可以制备出光滑且紧密结合的熔覆层,且表面硬度明显提高。