共查询到18条相似文献,搜索用时 203 毫秒
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钎料对金属/陶瓷钎焊接头残余应力的影响 总被引:1,自引:0,他引:1
采用热弹塑性有限元方法,在考虑材料性能参数随温度变化的情况下,分析了采用Ag-Cu-Ti钎料钎焊Al2O3陶瓷与镍丝钎焊接头在钎焊过程中产生的应力大小和分布情况.结果表明:钎焊过程中,在钎料与陶瓷界面的陶瓷侧会产生较大的残余拉应力,影响了钎焊接头的连接强度.在此类连接结构中,钎料对接头残余应力的影响是主要的,而钎料性能参数及厚度是决定接头残余应力大小的重要因素.在选择金属/陶瓷钎焊用钎料时,为降低接头残余应力,除考虑钎料与陶瓷的润湿性和界面反应程度外,钎料的性能参数和厚度同样重要. 相似文献
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《机电产品开发与创新》2001,(4):17-17
该项成果是机械工业技术发展基金项目成果。熔化极氩弧钎焊是靠钎料丝与被焊件之间的氩弧作热源加热被焊金属和钎料,钎料丝通过焊枪连续送入钎焊区域,整个钎焊过程始终起于氩气保护之下,而不需要使用钎剂。具有基体金属不熔化,焊后变形小,允许较大装配间隙,无焊后钎剂清洗和腐蚀等优点。钎料和钎焊专用电源是熔化极氩弧钎焊的主要技术关键。该成果研制了两种铜—硅—锰系钎料。都是以铜为基体添加了适量的硅、锰等元素的铜基钎料。其熔点低,BYA-1#熔化温度范围为920-940℃,BYA-2#为960-990℃,而国外用于氩弧钎焊的钎料熔… 相似文献
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吴新民 《机械工人(热加工)》1989,(5)
四、铝钎焊钎料有几种?用途是什么?铝钎焊钎料按熔点分类,可分为难熔钎料(熔点高于450℃),又称硬钎料;易熔钎料(熔点低于450℃),又称软钎料。一般钎焊时钎料要与钎剂共同配合使用。铝及铝合金钎焊用的易熔钎料(软钎料)按其熔化温度又可分为低温、 相似文献
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目前,我国自行车行业大都采用H62黄铜钎料盐浴浸沾钎焊。H62黄铜钎料的缺点是熔点较高,钎焊时对自行车材料的性能会引起不良的影响。为此,几年来我们在科研、生产及使用单位的密切配合下,研制出了牌号为HLCu-3的低熔点高强度钎料。经生产试用证明:HLCu-3钎料的性能是优良的,完全达到了生产要求,并在批量试生产的基础上通过了河南省省级鉴定。现将自行车用新钎料——HLCu-3的综合机械性能、钎料成分的选择和使用效果介绍如下。 相似文献
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研制一种Mg-Zn-Al-Er钎料。在钎料熔炼的过程中,对处于液态金属的钎料进行超声振动,超声功率为600 W,超声频率为20 kHz,超声处理时间为分别为0 s、60 s、120 s、180 s及240 s。钎料浇铸温度为600℃。研究结果表明,在液态钎料中施加超声波,可以起到净化钎料、细化晶粒及促进第二相α-Mg和Al3Er析出的作用。研制的Mg-Zn-Al-Er钎料的熔点不超过355℃,熔化区间不超过10℃,有利于钎焊的进行。对所研制的钎料进行炉中钎焊。钎焊过程中,熔点较高的Al3Er相仍可弥散分布于钎焊接头中,作为形核质点,细化晶粒。钎料超声处理时间为180 s时,其钎焊搭接接头剪切强度为59.7 MPa,为未经超声处理钎料搭接接头剪切强度的1.2倍。 相似文献
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《机械工程材料》2017,(10)
在Zn9.3Al7Cu合金钎料中添加了质量分数分别为0,0.1%,0.3%,0.5%的由镧粉和钕粉组成的混合稀土,研究了混合稀土含量对该合金钎料熔点、润湿性能、显微组织,以及对其钎焊铜/铝接头剪切强度的影响。结果表明:合金钎料的显微组织均由η(Zn)相、ε(CuZn5)相、β(ZnAl)共析相组成,混合稀土的添加使大树枝状的ε(CuZn5)相细化、分布变均匀;随着混合稀土含量的增加,合金钎料的熔点逐渐降低,润湿性能及其钎焊铜/铝接头的剪切强度均先增大后下降;当混合稀土质量分数为0.1%时,钎料在铜板和铝板上的铺展面积均达到最大,分别比未添加稀土的提高了20.4%和46.6%,其润湿铝板的界面变得连续,没有缺陷;合金钎料钎焊铜/铝接头的剪切强度也达到最大,为66.5MPa,比未添加稀土的提高了32.5%。 相似文献
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Cu基钎料电弧钎焊接头强度及断口分析 总被引:2,自引:0,他引:2
研究用钨极氩弧焊作为热源,用Cu3Si1Mn钎料、56Cu8Mn26Zn钎料分别钎焊A3钢板及1Cr18Ni9Ti不锈钢板。试验结果表明,在钎料/母材界面分别存在Si、Mn富集带,经XRD分析表明,Si是以Fe2Si相形式存在,而Mn是以固溶体形式存在;用Cu3Si1Mn、56Cu8Mn26Zn钎料钎焊A3钢板接头抗拉强度试样均断在母材,抗拉强度为308.2~308.7MPa,钎焊1Cr18Ni9Ti不锈钢板,拉伸均断在钎缝,其抗拉强度分别是331.5 MPa、382.9 MPa;拉伸断口分析发现,断裂起裂点在搭接钎缝的根部,主要是母材成分与少量的钎料成分混合、溶解而成,是脆性断口;止裂点在钎缝金属中(Cu3Si1Mn钎料)或在近界面上(Cu3Si1Mn钎料),是塑性断口。 相似文献
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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. 相似文献
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Fenggui Lu Binfeng Lu Xinhua Tang Shun Yao 《The International Journal of Advanced Manufacturing Technology》2008,37(9-10):961-965
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. 相似文献
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TiNi形状记忆合金与不锈钢钎焊接头的微观组织与性能 总被引:3,自引:0,他引:3
采用含Ag50%~68%、Cu10%~30%、Zn12%~20%、Sn0%~10%的银基钎料,通过激光钎焊,改变钎焊 有效热输入(激光输出功率和钎焊时间),研究了TiNi形状记忆合金与不锈钢异质钎焊接头的微观组织和性能。结 果表明:AgCuZnSn钎料对TiNi形状记忆合金和不锈钢的润湿性较好,钎焊接头界面平整、致密,与TiNi形状记 忆合金形成的界面反应层较窄,而与不锈钢形成的界面反应层较宽。钎焊有效热输入对TiNi形状记忆合金热影响 区组织和性能影响较大。钎焊有效热输入量过高,将导致TiNi形状记忆合金侧热影响区组织晶粒粗大、硬度降低、 塑性提高。严格控制钎焊工艺参数可以获得具有较高抗拉强度、形状记忆效应和超弹性的TiNi形状记忆合金与不 锈钢钎焊接头。 相似文献
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Ceramics are significantly used in many industrial applications due to their excellent mechanical and thermal properties such
as high temperature strength, low density, high hardness, low thermal expansion, and good corrosion resistive properties,
while their disadvantages are brittleness, poor formability and high manufacturing cost. To combine advantages of ceramics
with those of metals, they are often used together as one composite component, which necessiates reliable joining methods
between metal and ceramic. Direct brazing using an active filler metal has been found to be a reliable and simple technique,
producing strong and reliable joints. In this study, the fracture characteristics of Si3N4 ceramic joined to ANSI 304L stainless steel with a Ti-Ag-Cu filler and a Cu (0.25–0.3 mm) interlayer are investigated as
a function of strain rate and temperature. In order to evaluate a local strain a couple of strain gages are pasted at the
ceramic and metal sides near joint interface. As a result the 4-point bending strength and the deflection of interlayer increased
at room temperature with increasing strain rate. However bending strength decreased with temperature while deflection of interlayer
was almost same. The fracture shapes were classified into three groups ; cracks grow into the metal-brazing filler line, the
ceramic-brazing filler line or the ceramic inside. 相似文献
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Pengpeng LIAO Yucai ZHANG Guoyan ZHOU Xiancheng ZHANG Wenchun JIANG Shantung TU 《Frontiers of Mechanical Engineering》2022,17(4):46
The creep life of an aeroengine recuperator is investigated in terms of continuum damage mechanics by using finite element simulations. The effects of the manifold wall thickness and creep properties of brazing filler metal on the operating life of the recuperator are analyzed. Results show that the crack initiates from the brazing filler metal located on the outer surface of the manifold with the wall thickness of 2 mm and propagates throughout the whole region of the brazing filler metal when the creep time reaches 34900 h. The creep life of the recuperator meets the requirement of 40000 h continuous operation when the wall thickness increases to 3.5 mm, but its total weight increases by 15%. Decreasing the minimum creep strain rate with the enhancement of the creep strength of the brazing filler metal presents an obvious effect on the creep life of the recuperator. At the same stress level, the creep rupture time of the recuperator is enhanced by 13 times if the mismatch between the minimum creep rate of the filler and base metal is reduced by 20%. 相似文献