Al-Si-Cu-Mg 钎料真空钎焊6061铝合金工艺研究

为了解决6061铝合金熔点与现有货架产品Al-Si-Cu-Mg系钎料熔点较为接近、钎焊工艺难以控制的难题,开展了Al-Si-Cu-Mg系钎料钎焊6061铝合金的工艺研究.通过合理的焊接工艺参数试验设计,得出了合适的6061真空钎焊焊接工艺参数.对钎焊样件进行组织性能分析及耐腐蚀性试验,发现在合适的钎焊工艺参数控制下,钎焊接头中的Cu在焊缝区域产生了扩散,只有极少量的Cu与Al形成了共晶组织.中性盐雾试验结果表明,钎焊缝中极少量的Al-Cu共晶组织对其抗腐蚀性影响不大.     

钎焊温度对YG8硬质合金与1Cr18Ni9Ti不锈钢钎焊接头组织与力学性能的影响

以L304银焊片为钎料,对YG8硬质合金与1Cr18Ni9Ti不锈钢进行高温氩气保护钎焊,通过显微组织观察、能谱分析、硬度测试、室温剪切试验等,研究了钎焊温度对钎焊接头组织及力学性能的影响。结果表明:随着钎焊温度的升高,接头焊缝的组织更加均匀致密,钎料逐渐熔化且充分填充焊缝,钎焊质量变好,但当钎焊温度高于920℃时,钎焊接头出现过热现象,组织粗大,钎焊质量变差;随着钎焊温度的升高,钎焊接头的剪切强度和显微硬度均呈先增大后减小的趋势;当钎焊温度为910℃时,钎焊接头的剪切强度为147.5MPa,显微硬度为194HV,钎焊接头的综合力学性能最好。     

钎焊氧化锆增韧氧化铝陶瓷的组织与性能研究

采用纯银基钎料,在空气条件下对氧化锆增韧氧化铝陶瓷进行钎焊。以钎焊温度和保温时间为主要工艺参数,采用控制变量法进行试验,研究工艺参数对钎焊接头组织与性能的影响。研究结果表明,钎焊温度升高会使反应剧烈,保温时间延长会使反应程度加深,钎焊温度升高与保温时间延长在一定范围内均有利于提升钎焊接头的剪切强度。     

钎焊工艺参数对钎缝组织性能影响的研究

钎缝组织在很大程度上决定着钎焊接头的承栽能力及力学性能.通过采用多种方法对钎缝组织进行全面地观察与分析,揭示了钎焊工艺参数对接头力学性能的影响规律.试验表明,钎缝组织随着钎焊温度的提高、钎焊保温时间的延长,其成分变得不均匀、组织变得粗大,钎焊接头的承载能力较差.     

铝钎焊用锌基合金钎料的制备及钎焊接头的组织和抗剪强度

采用高频感应加热装置制备了锌基合金钎料,并以纯铝为母材进行润湿试验,并采用该钎料分别对2A12铝合金、55%SiCp/Al复合材料进行钎焊,分析了合金钎料的显微组织、成分、熔化温度范围,并对合金钎料及钎焊接头的拉剪强度进行了测试。结果表明:自制锌基合金钎料主要由α-Al固溶体、η-Zn固溶体和共晶组织组成,熔化温度区间为361~398℃;锌基合金钎料在纯铝上具有较好的润湿性;使用锌基合金钎料钎焊铝合金,其钎缝组织为η-Zn相、细小的共晶组织、树枝状及块状的α-Al相;钎焊55%SiCp/Al复合材料,其钎缝组织由铝的共析组织、η-Zn相、条纹状共晶组织及细小的共晶组织组成;钎料、2A12铝合金钎焊接头以及55%SiCp/Al复合材料钎焊接头的抗剪强度分别为237,127,109 MPa。     

二元及三元流高速铝叶轮的钎焊

二元流铝叶轮及新型设计的三元曲面叶片窄流道封闭式铝叶轮采用钎焊工艺连接轮盘和轮盖是最合适、最经济的方法之一。本文介绍了试验材料和试验程序；从钎剂、钎料的工艺性能、钎焊工艺参数对钎焊接头强度的影响，钎焊间隙对钎缝质量的影响等方面讨论了试验结果并进行了分析，给出了实际的钎焊叶轮工艺。     

非晶态钎料钎焊不锈钢的组织转变及性能研究

以非晶态BNi89P(P 11%wt)箔带钎料真空钎焊成分为1Cr18Ni9Ti的不锈钢为试件,采用差热分析DTA、X射线衍射仪(XRD)、电子探针EPMA-1600以及金相显微镜等测试手段,研究在钎料液相线、固相线及固相线以下温度进行钎焊时,钎焊温度及冷却方式对钎焊接头抗拉强度和组织转变的影响。实验结果表明:随着钎焊温度的逐渐升高,钎焊接头抗拉强度逐渐增加;快速冷却方式下的钎焊接头抗拉强度明显高于随炉冷却方式下的钎焊接头抗拉强度。     

钎焊新材料在电冰箱铜管蒸发器上的应用

介绍了冰箱生产中涉及到的钎料 L2 0 1取代 L2 0 8的钎焊技术 ,对钎焊接头的钎焊方法及工艺、钎焊接头的质量检验方法进行了具体分析。     

片式微波组件激光软钎焊气密封装技术研究

文中对片式微波组件激光软钎焊气密封装工艺开展研究,优化了影响焊缝成形的焊接结构、热台温度、助焊剂、离焦量、激光功率、焊接速度等工艺参数,分析了激光软钎焊密封接头微观组织,测试了激光软钎焊密封组件的气密性。结果表明:激光软钎焊封盖过程是一个温度场不断变化的动态过程,因此激光功率和焊接速度两参数也应在一定范围内通过程序设计动态调节。钎料可完全填充壳体与盖板之间形成的间隙,钎料中无空洞和裂纹,钎料未溢流到壳体内部。钎料与镀Ni 层接触并润湿良好,在钎料与壳体和盖板界面未形成粗大脆性的金锡金属间化合物。接头上部钎料基本保持(Sn)+(Pb)共晶组织状态,接头下部镀Ni层与钎料之间形成薄且均匀连续的金属间化合物层AuSn和AuSn₂。采用优化后的工艺参数激光软钎焊密封的组件气密性满足机载有源天线阵面应用要求。     

快速凝固态Sn2.5Ag0.7Cu钎料钎焊接头的显微组织

采用单辊法制备了快速凝固态Sn2.5Ag0.7Cu钎料合金,在相同钎焊工艺条件下,用扫描电镜及能谱仪、拉伸试验机研究了普通和快速凝固态钎料对紫铜板钎焊接头的组织、断口形貌、界面化合物和接头性能。结果表明:与普通钎料相比,快速凝固态钎料钎焊接头组织细化,初生β-Sn相尺寸减小而数量增多、共晶组织明显减少,并且初生相与共晶组织界线变得模糊;剪切断裂时形成的韧窝更多,钎焊接头的韧性得到提高。     

Effect of brazing temperature on the shear strength of Inconel 600 joint

In this study, Inconel 600 alloy was brazed by using Cusil ABA which is an active filler alloy in a high-vacuum condition under a pressure of 1?×?10^?4 Pa. Three brazing temperatures (830, 865, and 900 °C) were chosen based on the solidus temperature of AgCuTi filler alloy in order to investigate the effects of these temperatures on the performance of the brazed joint. Brazing processes were carried out over a period of time (15 min) to ensure that the filler alloy was melted completely. The performance of the brazing process was evaluated in terms of bonding strength by shear test, whereas microstructural analysis was performed to investigate the bonding morphology. The results revealed that a maximum value of shear strength (223.32 MPa) was obtained at a brazing temperature of 865 °C compared with other temperatures. It was also observed morphologically that the highest shear strength was influenced by the formation of two reaction layers that crossed in the center of the brazed area due to interdiffusion effect of several constituents from the Inconel 600 alloy and active brazing filler.     

铸态镍基钎料高温蠕变特性的试验研究

为了正确评价钎焊接头的高温力学性能,采用铸态非晶态BNi-2钎料来模拟实际钎缝材料,测定其基本蠕变特性,并与0Cr18Ni9不锈钢进行比较。结果表明：高温下BNi-2铸态钎料蠕变韧性低,蠕变应变速率小,对应力水平比较敏感,其本构关系可用Kachanov-Robatnov方程描述。     

Optimization of brazing conditions for OFHC Cu and ASTM A501 low carbon steel by taguchi method

This paper concerns the optimization of brazing conditions for joining the two dissimilar materials Oxygen-free high conductivity (OFHC) copper and ASTM A501 low carbon steel usually used for an Oil-Separator of an air-conditioner using Ag-based (BAg) alloy as a brazing filler metal (BFM). A mixture of 70% N₂ and 30% H₂ gases was used to prevent oxidation of the joints during furnace brazing process. Brazing joint clearance, length, temperature, and time were selected as design parameters that have significant effect on the bonding strength of a brazed joint. Taguchi method was used as a statistical technique for design of experiment (DOE) in an attempt to optimize brazing conditions in terms of shear strength. L₉ (3⁴) orthogonal array was designed for conducting the experiments. The relative influence of design parameters and their interaction on the response were also discussed. The experimental results verified that the brazing conditions predicted in this study by Taguchi method could produce the brazed joint between OFHC copper and ASTM A501 low carbon steel with maximum shear strength.     

高效散热微通道液冷冷板焊接技术及成形工艺研究

通过分析微通道冷板的结构特点及技术要求,对微通道冷板的焊接方法、焊接工艺进行了分析研究.采用气保护炉钎焊方法,通过巧妙地采用过渡材料与接头设计,既突破了6063铝合金气保护炉钎焊的钎焊性较差的技术难题,满足了钎焊缝密封性要求,又可有效地避免钎料流入微通道.通过焊接工装及接头设计,在合理的工艺及气氛条件下,实现了6063铝合金微通道冷板的整体焊接成形,解决了微通道冷板的焊接技术难题.     

基于GA-BP神经网络的PDC刀头钎焊残余应力优化分析

针对PDC硬质合金基底与45钢焊后残余应力对刀头钎焊强度的影响,在对钎焊残余应力进行有限元分析的基础上,利用MATLAB平台,将BP神经网络与遗传算法应用于钎焊参数优化设计。首先设计正交试验样本,对样本进行有限元模拟获得最大钎焊残余拉应力,并作为基于遗传算法优化的BP神经网络的导师信号;利用遗传算法,把减小最大残余拉应力作为目标,得到钎焊最优参数;最后通过数值仿真验证,计算数值模拟结果与遗传算法预测结果相吻合。     

铝制散热器真空钎焊性能及微观组织研究

探索铝制散热器真空纤焊最佳工艺参数,然后对散热器进行水压试验,并对试件断口进行了分析。同时对钎焊接头进行了金相试验、扫描电镜实验以及点成分分析。试验结果说明,在选定的工艺参数之下,钎焊接头水压试验数值能达到15MPa,钎焊断口呈混合断裂的形式。在钎缝中生成了网状的共晶组织,皮层中的Si熔融之后重新结晶,形成条状的Si相,在晶粒边界上析出,这些富Si相的存在成为了接头断裂的一个主要原因。     

钎焊金刚石薄壁小孔钻研制

以Ni-Cr合金为钎料,分别用真空加热和高频感应加热两种方式进行了金刚石磨粒与0Cr18Ni9不锈钢基体的钎焊,制作了基体外径为3 mm的薄壁小孔钻头。进行了半钢化玻璃钻削试验,用扫描电子显微镜观察钻削试验前后钻头的微观形貌。结果表明:两种钎焊工艺皆实现了金刚石磨粒的高强度连接;加热源不同及金刚石磨料出露高度差异性是影响钻头磨损方式的主要因素;为确保钻头的寿命和高效,磨粒出露高度应控制在其自身高度的50%-60%之间。     

LT-3铝合金真空钎焊钎缝微观组织分析

对LT-3铝合金真空钎焊工艺进行了研究，利用显微硬度仪、扫描电镜和X射线衍射仪对未焊接母材和钎缝中生成的相和组织进行了分析，并对钎焊接头的断口形貌进行了分析。结果表明：钎缝的显微硬度平均值要比芯层显微硬度的平均值高24．5MHV；钎缝中生成了网状的共晶组织和多种新的金属间化合物；钎缝断裂过程属于混合断裂，断口界面上可以看到多种断裂形貌。     

Study of influencing factors and joint performance of laser brazing on zinc-coated steel plate

Laser brazing is applied to the zinc-coated steel plate welding for its superior processing property. The delivery stability of filler metal such as the position of filler wire tip relative to laser focal point centre and the existence time of liquid filler metal are the key technologies in laser brazing. Also, due to the addition of the filler metal, the changeable factors increase in the process of brazing, so matching and optimizing of the processing parameters are important. In this paper, different influencing factors of laser brazing such as wire feeding stability, laser power distribution and galvanized layer, and parameters affecting the laser brazing process including the laser system, base material, filler metal and processing conditions were analysed and tested by experiments. Optimizing parameters were also acquired and used to laser braze lap joint of zinc-coated steel plate. Joint performance and quality were tested by micro-hardness testing, macro-metallographic analysis and SEM analysis. The results proved that laser brazing joints have good intensity and corrosion resistance.