共查询到18条相似文献,搜索用时 203 毫秒
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使用SPH-FEM耦合算法对钛-钢、钢-不锈钢、铜-钢、钛-铝4种常见爆炸复合组合进行了数值模拟,理论分析了材料JC强度方程和SG强度方程的适用应变率范围。探讨了爆炸焊接静态参数基复板厚度和动态参数碰撞速度、动态弯折角对界面温度和压力的影响,借助数值模拟手段研究了界面波形形貌,漩涡和少量飞溅熔化块的生长机理。结果表明,随着复板厚度和碰撞速度的增加,界面温度、压力和波形尺寸明显增加,动态弯折角和基板厚度的改变并不能影响界面温度,界面波形生长遵循着“主逆次顺”运动规律。 相似文献
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应用水下爆炸焊方法进行了NiTi形状记忆合金与铜箔的爆炸焊研究.利用大型有限元软件ANASYS/LS-DYNA对水下爆炸冲击波驱动飞板的飞行过程进行了数值模拟.飞板的飞行速度与爆炸焊产生射流的最小碰撞速度对比表明,可以实现焊接.通过分析微观组织和断裂机理,评估复合板焊接效果.结果表明,微观组织观察显示界面为连续均匀的波纹形态,界面结合处无裂纹,焊接性能良好.断口形貌分析显示断裂主要表现为解理和准解理断裂,界面处端口形貌与微观组织形态观察一致.水下爆炸焊方法将解决脆性、薄板金属用传统爆炸焊方法难以焊接的问题. 相似文献
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基于爆炸焊接波状界面形成的失稳机理与流体—弹塑性模型,在飞板反向射流与空气之间存在着Rayleigh-Taylor、Kelvin-Helmholtz不稳定性条件,因而提出失稳是发生在金属流体薄膜与空气之间。由界面波幅与波长之比判定线性理论成立,从而建立双层流体失稳线性控制方程,获得失稳发展特征指数表达式。结果表明在金属流体弹—粘性与失稳机制竞争作用下,特定波长范围的扰动能够被优先发展,其他波长的扰动被抑制或未能发展,从而使得波状界面在沿爆轰方向较为一致,实验结果也验证了这一结论的正确性。 相似文献
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祖国胤 《稀有金属材料与工程》2017,46(4):906-911
本文表征了钛/钢爆炸焊接复合板的界面组织和剪切性能,研究爆炸复合过程的界面结合机理。结果表明,在金属板之间形成了波状界面组织,剧烈塑性变形造成钢基体发生明显的塑性流动,并在界面形成连续的漩涡形貌。TEM和XRD检测证实界面存在纳米尺度的过渡层,并包含有固溶体组织和少量金属间化合物。波状界面组织改善了复合板沿爆炸方向的界面剪切强度,剪切断口显示漩涡组织发生韧性断裂形貌。 相似文献
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为了研究在爆炸焊接过程中波状界面的形成机理,本文采用对不同强度基板爆炸焊接实验与SPH数值模拟相结合的方式对试样界面形貌及其焊接过程进行了分析。实验发现当焊接参数在可焊窗口以内时,强度较低的材料界面比较容易形成周期性波纹,而且数值模拟结果显示在碰撞点后两个周期的范围内,界面粒子仍然具有较高的运动速度并沿界面持续运动形成界面波;而强度较高且表面光滑的材料则难以形成波状界面。结果表明:爆炸焊接波状界面的形成需要扰动的积累进而触发Bahrani刻入机理,而当界面缺少扰动时则难以形成波状界面;在碰撞点离开后的两个周期范围内,波状界面的熔融金属将沿界面持续运动最终形成稳定的界面波。 相似文献
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对爆炸复合的钛/钢复合板进行了一道次60%的温轧,研究了一道次温轧钛/钢爆炸复合板的近界面微观组织及剪切强度。结果显示,一道次温轧工艺可以引起钛层和钢层近界面组织的显著剪切变形。由于剪切变形,钛层形成了RD分散织构。钢层含有高组份的旋转立方织构及低组份的γ纤维织构。对比常规多道次轧制方法,由于剪切变形可细化界面化合物,使得一道次温轧钛/钢复合板抗剪切强度得到提升。 相似文献
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为了提高爆炸能量的利用率,减少焊接药量,提出采用自约束结构炸药进行爆炸焊接。采用T2铜板和Q345钢板分别作为复板和基板,通过理论计算得到T2/Q345爆炸焊接窗口。采用双层蜂窝结构炸药作为自约束结构焊接炸药,对T2铜与Q345钢的爆炸焊接进行了试验研究。通过力学性能测试和显微组织观察,研究了T2/Q345复合板的结合性能。结果表明:与爆速为2505和3512 m·s-1的单层炸药相比,T2/Q345复合板爆炸焊接采用的双层蜂窝结构炸药量分别减少了54.4%和31.4%;随着传播距离的增加,复合板的结合界面由直线结合向波状结合转变。复合板的抗拉剪切强度为237.0 MPa,满足T2/Q345复合板的结合强度要求。爆炸产生的硬化发生在结合界面附近,采用双层蜂窝结构炸药爆炸焊接得到的T2/Q345复合板具有良好的结合性能。 相似文献
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为提高炸药能量利用效率、降低能量耗散,利用自约束结构炸药进行爆炸焊接研究.以T2铜和Q345钢分别作为复层与基层,自约束结构炸药作为焊接炸药,借助ANSYS/AUTODYN软件模拟爆炸焊接过程,并进行T2/Q345爆炸焊接试验,对复合板试件进行拉剪性能检测和微观形貌观察分析其焊接质量.结果表明,T2/Q345爆炸焊接的碰撞速度距起爆端100 mm后均大于临界碰撞速度345 m/s,距起爆端150 mm处碰撞速度达到最大值567 m/s.T2/Q345复合板起爆端呈直线结合,并随着传爆距离增加变为波形结合.T2/Q345复合板远离起爆端的平均剪切强度为237.0 MPa,断裂位置位于铜一侧.试件被拉剪破坏后的铜层出现加工硬化现象,远离结合界面的显微硬度和塑性变形程度呈增强趋势.自约束结构炸药可降低自身爆炸产物飞散,使炸药能量更多地转化为复层动能,提高能量利用率. 相似文献
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In order to investigate the bonding behavior and mechanism of the interface prepared by explosive welding,the bonding interfaces of OCr18Ni9/16MnR were observed and analyzed by means of optical microscope(OM),scanning electron microscope(SEM)and electron probe microanalysis(EPMA).It is found that the welding interfaces are wavy due to the wavy explosive loading.There are three kinds of bonding interfaces i.e.big wave,small wave and micro wave.There are a few seam defects and all elements contents are less than both of the base and flyer plate in the transition zone of big wavy interface.Moreover,some"holes"result in the lowest bonding strength of big wavy interface nearby the interface in the base plate.All elements contents of the small wavy interface are between two metals,and there are few seam and hole defects,so it is the higher for the bonding strength of small wavy interface.There is no transition zone and defects in the micro wavy interface,so the interface is the best.To gain the high quality small and micro wavy bonding interface the explosive charge should be controlled. 相似文献
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为解决传统爆炸焊接中能量利用率和工作效率较低的问题,提出了一种多层爆炸焊接新方法.以五层爆炸焊接为例,304不锈钢板和Q235钢板分别作为复板和基板,进行了多层爆炸焊接和传统单层爆炸焊接的对比试验,并对爆炸焊接窗口和复板碰撞速度进行了理论计算. 结果表明,与传统爆炸焊接技术相比,五层爆炸焊接中可节省炸药量63%,并且五层爆炸焊接技术通过一次爆炸作业可获得五块焊接板,有利于提高爆炸焊接作业的工作效率. 此外,得到了304不锈钢和Q235钢的爆炸焊接窗口并对结合质量进行了预测,试验和预测结果吻合良好. 相似文献
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Wei Sun Xiaojie Li Honghao Yan Kazuyuki Hokamoto 《Journal of Materials Engineering and Performance》2014,23(2):421-428
This paper aims at investigating effects of initial hardness on interfacial features for identical compositional materials under identical welding conditions. Two underwater explosive welding experiments on tool steel SKS3 with copper foil were carried out: one as-received and the other heat-treated. The welding process was simulated using the commercially available software package LS-DYNA. Numerical simulation gave deformation of the flyer/base plate and pressure distribution during the welding process. Microstructure and hardness at interface of the welded metals were evaluated. The results indicate that decreasing impact energy is accompanied by a shift from wavy to linear interface. Moreover, a comparison of the two experiments allows the conclusion that high initial hardness results in a decrease of wavelength and amplitude under identical welding conditions. Hardness profiles of as-received tool steel-copper welding reveal the hardening effect of impact in the vicinity of the interface. However, of interest is that a decrease in hardness was seen in the case of heat-treated martensitic tool steel with copper, fundamentally differing from previous explosive welding research; phase transition is proposed to discuss the relation between the effects of impact and heat, and those of work hardening and softening. 相似文献
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为了解决钛-铝在爆炸焊接过程中可焊性低并容易产生脆性金属间化合物等技术难题,选用低爆速粉状乳化炸药为试验用药,下限装药厚度和上限基复板间距为工艺参数,成功获得了100%复合的“1 + 14 + 1”TA2 - 1060 - TA2双面金属复合板. OM, SEM, EDS测试结果表明,复合板界面呈良好小波状结合;基复板流在波峰阻挡以及复板挤压作用下形成漩涡结构,其内部存在包覆熔融金属的铸锭组织;结合界面附件发生不同程度的元素扩散. 力学测试结果表明,复合板的弯曲强度为288 MPa、抗拉强度为165.5 MPa、界面处显微硬度峰值为227 HV,满足工业生产要求. 相似文献
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C.G. Shi Y.H. Wang L.G. Cai C.H. ZhouEngineering Institute of Engineering Corps PLA University of Science Technology Nanjing China 《金属学报(英文版)》2003,16(6):531-537
There are four new achievements of this work on the theory and technology of explosive welding.(1) It has been found and defined three kinds of bonding interfaces: big wavy, small wavy and micro wavy, and the micro wavy interface is the best. In a cladding plate, it is for the first time to find that the form of interface presents regular distribution.(2) Although the interface has the features of melt, diffusion and pressure welding in the mean time, the seam and "hole" brought by the melt weaken the bonding strength of interface greatly, and the effect of melt on interface must be eliminated in explosive welding, so explosive welding is not a melt weld. The diffusion welding is a kind of form of pressure welding, and the diffusion is not the reason of the bonding of interface but the result of interface high pressure. So the diffusion welding cannot also explain the bonding mechanism of it. The experiment and theory make clear that explosive welding is a special pressure one.(3) To get good interface 相似文献