Ga元素含量对银钎料组织及性能的影响

研究了Ga元素的添加对B17AgCuZnSn钎料固液相线温度、铺展性能、显微组织以及钎焊接头抗拉强度的影响规律. 采用火焰钎焊方法,得到H62黄铜与304不锈钢的对接接头. 结果表明,随着Ga元素含量的增加,B17AgCuZnSn钎料固液相线温度出现下降,在母材表面的铺展性能有所上升,B17AgCuZnSn-2Ga钎料铺展试验中出现“润湿环”现象. Ga元素的添加改善了银钎料的显微组织,当Ga元素质量分数为2%时B17AgCuZnSn钎料组织细小均匀. 此外,采用该系列钎料钎焊黄铜和不锈钢时,得到了致密无缺陷的钎焊接头,当B17AgCuZnSn钎料中Ga元素质量分数为2%时,钎焊接头的抗拉强度达到最大值387.2 MPa.     

低银BAg10CuZnSnInNd钎料组织与性能

研究了复合添加微量In和Nd元素对低银BAg10CuZnSn钎料熔化特性、润湿性能、显微组织及钎焊接头力学性能的影响.结果表明,In元素的添加可以显著降低钎料的固、液相线温度,而Nd元素对钎料的固、液相线温度没有明显的影响.适量In元素和Nd元素的添加可以显著提高钎料在304不锈钢和紫铜上的铺展面积,同时钎料的显微组织得到了明显细化,过量添加In元素和Nd元素后钎料组织中出现了富铟相和稀土相.当In和Nd元素的添加量分别为2%和0.1%时,304不锈钢/304不锈钢接头的抗剪强度达到最大值430 MPa,而304不锈钢/紫铜的钎焊接头发生断裂,且均断于紫铜处,说明钎焊接头的强度大于紫铜.     

Cr对Ni-P系钎料钎焊不锈钢接头性能的影响

研究了钎焊温度对Ni-P系钎料铺展件能及其真空钎焊OCr13不锈钢接头力学性能的影响.结果表明,Ni-P系钎料铺展面积随钎焊温度的升高而增大,并且相同温度下不含Cr的Ni-P钎料铺展面积大于Ni-Cr-P的铺展面积;钎焊温度从925℃升高到1000℃过程中,Ni-P、Ni-Cr-P钎料钎焊不锈钢接头的室温剪切强度均增大,并且在相同钎焊工艺下,不含Cr的Ni-P钎料钎焊不锈钢接头室温剪切强度优于Ni-Cr-P钎焊接头强度30～40MPa;Ni-P系钎料钎焊接头高温强度随温度升高而下降,测试温度超过500℃时,相同温度下含Cr的钎料能够提高钎焊接头强度0～30 MPa.     

特种钎剂辅助铝/钢异种合金TIG熔-钎焊

采用铝硅钎料进行了铝/钢异种合金TIG熔-钎焊试验,开发出了适用于TIG电弧热源下的特种钎剂,通过高速摄影观察了液态钎料的润湿铺展行为,并分析了接头特性.结果表明,特种钎剂能够显著促进钎料的润湿铺展,钎剂成分(质量分数,%)为:改性的Noclock钎剂(KAlF4:K3AlF6,65:35)55～78,Zn10～20,Sn10～20,K2SiF62～5.液态钎料的铺展包括两部分:一是通过成形槽,沿钢背面进行铺展,获得良好的背面成形;二是沿坡口表面进行"上坡"铺展,实现焊缝正面成形.铝/钢TIG熔-钎焊接头具有熔焊与钎焊的双重性质,接头抗拉强度可达115.5MPa,断裂于焊缝/不锈钢界面层.     

铟对低银Ag-Cu-Zn钎料显微组织和性能的影响

研究了低银Ag-Cu-Zn钎料(ωAg≤20%)的熔化特性、铺展性能、钎料显微组织。以黄铜/304不锈钢作为母材,采用火焰钎焊方法,进行了搭接钎焊试验。结果表明,低银Ag-Cu-Zn钎料显微组织主要由铜基固溶体、银基固溶体、Cu Zn化合物相构成。In的添加降低了Ag-Cu-Zn钎料的固、液相线温度,改善了钎料润湿性能;添加In的低银Ag-Cu-Zn钎料在凝固过程中析出富In的银基固溶体,起到了固溶强化的效果,改善了钎焊接头的显微组织,从而提高了钎缝接头的力学性能。使用17Ag Cu Zn-1In火焰钎焊黄铜/304不锈钢,钎焊接头成形美观、组织致密、无缺陷存在,综合性能与含银量为25%的BAg25Cu Zn Sn银钎料的性能相当,节银效果显著。     

Ag,Al,Ga对Sn-9Zn无铅钎料润湿性能的影响

采用润湿平衡法测试了Sn-9Zn-X(X为Ag,Al,Ga)无铅钎料分别配合ZnCl2-NH4Cl钎剂和免清洗助焊剂,在空气和氮气保护的两种条件下的润湿性能,分析研究了合金元素Ag,Al,Ga的添加量对Sn-9Zn-X无铅钎料润湿性的影响规律.结果表明,合金元素Ag,Al,Ga在Sn-9Zn中的最佳添加量(质量分数)分别为0.3%,0.005%～0.02%,0.5%.采用氮气保护可以显著改善Sn-9Zn-X无铅钎料的润湿性,而Sn-9Zn-X无铅钎料配合ZnCl2-NH4Cl钎剂时具有较好的润湿性,甚至优于Sn-3.5Ag-0.5Cu在相同条件下的润湿性.这一研究结果表明,通过研发适合于Sn-Zn系无铅钎料的高性能助焊剂,从而改善Sn-Zn系钎料的润湿性能是完全可行的.     

TC4钛合金/304不锈钢异种材料蜂窝结构钎焊工艺

采用Ti-37.5Zr-15Cu-10Ni和Ag-28Cu两种钎料分别对TC4钛合金面板/304不锈钢蜂窝芯异种材料蜂窝结构进行了钎焊,对钎焊界面组织和蜂窝结构的力学性能进行了对比分析. 结果表明,Ti基钎料与304不锈钢蜂窝芯箔材界面润湿反应性能较差且Ti基钎料钎缝显微硬度较高,导致钎焊界面强度低,蜂窝拉伸力学性能差. Ag基钎料与304不锈钢蜂窝芯箔材和TC4面板均发生显著的界面反应,钎焊温度830 ℃,保温时间10 min时,蜂窝抗拉强度为10.35 MPa,呈蜂窝芯破坏特征. Ag基钎料蜂窝抗拉强度明显优于Ti基钎料结果,适用于TC4钛合金面板/304不锈钢蜂窝芯异种材料蜂窝钎焊.     

真空钎焊TiAl基合金用Ti-Zr-Cu-Ni-Co-Mo钎料的钎焊性能（英文）

采用非晶和晶态Ti-25Zr-12.5Cu-12.5Ni-3.0Co-2.0Mo(质量分数,%)钎料对Ti-47Al-2Nb-2Cr-0.15B(摩尔分数,%)合金进行真空钎焊连接,对两种钎料的熔化行为、润湿铺展性、填缝隙能力以及由钎焊TiAl基合金所得的钎焊接头进行详细的研究。结果表明:与晶态钎料相比,非晶钎料具有更窄的熔化温度区间、更低的液相线温度和熔化激活能;同时,非晶钎料在Ti-47Al-2Nb-2Cr-0.15B合金表面上具有更优异的钎焊性。非晶和晶态两种钎料的钎焊接头均由两侧的界面反应层和中心钎焊层组成,非晶钎料钎焊接头的抗拉强度均高于相同钎焊工艺参数下的晶态钎料钎焊接头的抗拉强度,且在钎焊温度1273K下获得的钎焊接头的抗拉强度达到最大值254 MPa。     

Ga2O3对Ag30CuZnSn药芯银钎料钎缝组织及钎焊接头性能的影响

向Ag30CuZnSn药芯银钎料药粉中添加Ga₂O₃,研究了Ga₂O₃对Ag30CuZnSn药芯银钎料钎缝组织的影响及钎焊接头性能的影响. 结果表明,微量Ga₂O₃可以显著提高Ag30CuZnSn药芯银钎料的润湿铺展性能且可以减少药芯中钎剂的添加量. Ga₂O₃添加量为0.4%（质量分数）时,钎料润湿铺展性能和钎焊接头抗剪切强度达到最佳值. 这是因为Ga₂O₃属于表面活性物质,可以显著降低熔融钎料和母材之间的界面张力,从而提高了钎剂粉末的去膜效果,进而提高银钎料的润湿铺展性能. 药芯银钎料基体及钎缝组织主要由以CuZn相为主的固溶体、银基固溶体和铜基固溶体构成. 火焰钎焊时,添加0.4%Ga₂O₃（质量分数）时作用效果最佳,钎缝组织的细化与钎着率的提高(钎着率提高至95%以上)使得钎焊接头抗剪强度提高了11%以上,钎焊接头断口组织的形貌证明了上述结果.     

锌铝合金软钎剂的研究及分析

研制了多种有机和无机软钎剂,对各钎剂进行了对比实验,确定了适合锌铝合金钎焊的无机软钎剂.对该钎剂进行了不挥发物含量、腐蚀率试验.结果表明:ZnCl2-NH4Cl-KF钎剂可以有效去除锌铝合金表面氧化膜和钎焊过程中形成的氧化物;促进钎料的润湿;钎剂残渣的腐蚀性小,残余少且清除容易.     

稀土元素Ce对Sn-Cu-Ni无铅钎料铺展性能及焊点力学性能的影响

研究了不同含量稀土元素Ce对Sn-Cu-Ni钎料铺展性能及其焊点力学性能及钎料显微组织的影响规律.结果表明,随着稀土元素Ce含量的增加,钎料在铜基板上的铺展面积逐渐增大,当Ce元素含量达到0.05%时,钎料的铺展面积达到最大.Sn-Cu-Ni钎料中添加适量的稀土元素Ce,能够细化钎料组织,从而提高焊点的力学性能.当Ce元素的含量为0.05%左右时,焊点的力学性能达到最佳值.Ce元素含量超过0.05%后,继续增大稀土元素Ce的添加量,Sn-Cu-Ni钎料的显微组织又变得粗大,铺展性能有所降低,焊点力学性能也随之有所下降.     

Sn-Zn系钎料专用助焊剂

采用铺展试验法研究了Sn-9Zn钎料配合自制Sn—Zn系钎料专用助焊剂、NH4Cl-ZnCl2助焊剂、树脂型助焊剂以及水溶性助焊剂在铜板上的铺展能力。结果表明,使用自制助焊剂A。匹配Sn-9Zn钎料铺展性能相比其它助焊剂铺展面积明显增大．自制助焊剂不含卤素,钎料的铺展面积最大为65．7mm2,相比NH4C1-ZnCl2助焊剂、树脂型助焊剂、水溶性助焊剂分别提高了16．1％,116．1％,85．1％．此外,复配助焊剂能进一步促进钎料在铜板上的铺展,最大铺展面积分别达到76．5,72．5mm2,控制磺酸亚锡的含量为20％（质量分数）,二乙醇胺,丁二酸的最佳添加量依次为8％,10％（质量分数）．     

Effects of activating fluxes on pulsed laser beam welded AZ31 magnesium alloy

Abstract

Effects of activating fluxes on macromorphologies, microstructures and mechanical properties of low power pulse laser beam welding of AZ31 magnesium alloy joints were investigated by microstructural observations and mechanical properties tests (including the ultimate tensile strength and hardness). The results showed that activating flux (SiO₂) is more effective in improving the laser welded penetrations when the heat input is at a critical value (E?=?53·42 J mm^?1). Five typical fluxes (SiO₂, TiO₂, ZnCl₂, CaCl₂ and CaF₂) all increased the weld penetrations and D/W ratios of the welded joints. The morphologies of grains in the band zones with fluxes are characterised by dendritic crystals. Moreover, the widths of the band zones with oxide and chloride fluxes are wider than that with fluorine flux. The mechanical properties of the welded joints with fluxes were lower than those without flux. The fracture surface of the welded joints with fluxes exhibited a character of a mixed fracture.     

Contact Reactive Joining of TA15 and 304 Stainless Steel Via a Copper Interlayer Heated by Electron Beam with a Beam Deflection

TA15 titanium alloy and 304 stainless steel were joined via a copper interlayer heated by electron beam with a beam deflection towards the stainless steel. Microstructures of the joints were analyzed by optical microscopy, scanning electron microscopy, and X-ray diffraction. The tensile strengths of the joints and the ultramicrohardness of the intermetallic compounds were also measured. The results showed that the joint was formed by three kinds of metallurgical processes. Copper interlayer and TA15 were joined by contact reaction with the reaction products of CuTi, Cu₄Ti₃, and Cu₂Ti. While copper interlayer and 304 stainless steel were joined by fusion and solid state diffusion process. Tensile strength of the joint can reach to 300?MPa, equivalent to 55% of that of 304 stainless steel. Furthermore, the tensile strength was mostly dependent on the volume of the unmelted copper sheet, although the intermetallics layer was the weakest location in the joint.     

Sn-Cu-Ni焊点纳米压痕试验分析

为研究金属间化合物与无铅焊点力学性能之间的关系,采用纳米压痕法测定了Sn-Cu-Ni焊点中金属间化合物及钎料基体的弹性模量和压痕硬度等力学性能参量．结果表明,Sn-Cu-Ni焊点中（Cu,Ni）6Sn5金属间化合物的弹性模量为113．2GPa±4．8GPa,压痕硬度为5．59GPa±0．32GPa,均与钎料基体有较大差...     

Development of high strength stainless steel brazed joints using rapidly solidified filler alloys

Abstract

Two types of rapidly solidified filler alloys of nominal composition Cu–40Mn–10Ni (C50) and Ni–7Cr–3·2B–4·5Si–3Fe (N82) were used for stainless steel (SS304) brazing joints. The C50 foil is crystalline in nature, whereas N82 foil shows amorphous structure. The SS304/C50/SS304 joint shows solid solution phases at interfacial area, with maximum bond strength of 500 MPa, which qualifies to 80% of base metal strength. Conversely, the SS304/N82/SS304 joint develops brittle Cr_xB_y intermetallic phases, which lowers bond strength to 330 MPa.     

Cu/Sn-58Bi-xEr_2O_3/Cu钎焊接头微观组织和力学性能的研究

研究了不同含量的纳米Er_2O_3颗粒对Sn-58Bi钎料的铺展性能、钎焊接头微观组织和力学性能的影响。结果表明,添加微量的纳米Er_2O_3颗粒细化了Sn-58Bi钎料的微观组织、改善了Sn-58Bi钎料的铺展性能和力学性能。当纳米Er_2O_3颗粒的添加量为0.075%(质量分数)时,Sn-58Bi复合钎料得到了最佳的铺展性能,比Sn-58Bi钎料的铺展系数增大了5.1%;当添加量为0.05%(质量分数)时,Sn-58Bi钎料的组织明显细化且到了最大的抗拉强度89 MPa,比Sn-58Bi共晶钎料的抗拉强度增大了11.5%。     

Influence of bismuth on microstructure,thermal properties,mechanical performance,and interfacial behavior of SAC305-xBi/Cu solder joints

This research sought to improve the properties of SAC305 solder joints by the addition of 1 and 2 wt.% Bi. The effects of bismuth doping on the microstructure, thermal properties, and mechanical performance of the SAC305-xBi/Cu solder joints were investigated. Bi-doping modified the microstructure of the solder joints by refining the primary β-Sn and eutectic phases. Bi-doping below 2 wt.% dissolved in the β-Sn matrix and formed a solid solution, whereas Bi additions equal to or greater than 2 wt.% formed Bi precipitates in the β-Sn matrix. Solid solution strengthening and precipitation strengthening mechanisms in the β-Sn matrix increased the ultimate tensile strength and microhardness of the alloy from 35.7 MPa and 12.6 HV to 55.3 MPa and 20.8 HV, respectively, but elongation decreased from 24.6% to 16.1%. The fracture surface of a solder joint containing 2 wt.% Bi was typical of a brittle failure rather than a ductile failure. The interfacial layer of all solder joints comprised two parallel IMC layers: a layer of Cu₆Sn₅ and a layer of Cu₃Sn. The interfacial layer was thinner and the shear strength was greater in SAC305-xBi/Cu joints than in SAC305/Cu solder joints. Therefore, small addition of Bi refined microstructure, reduced melting temperature and improved the mechanical performance of SAC305/Cu solder joints.