槽型界面爆炸复合板界面效应及结合机理的研究
发布时间：2018-09-14 17:07
【摘要】：爆炸焊接是利用炸药爆炸能量使高速碰撞的界面金属产生塑性流动和冶金结合的一种工艺,已成功实现数百种金属的复合,广泛应用于层状金属复合板的制备。但传统爆炸焊接炸药用量很大,造成严重的环境污染、振动和噪声。而且受到爆炸焊接窗口限制,当焊接能量较小时界面金属无法产生塑性流动和金属射流,难以实现复合,而当焊接能量较大时易产生过熔现象,造成界面的结合强度不高,甚至被反射拉伸波拉开。针对目前爆炸焊接存在的诸多问题,提出采用蜂窝结构炸药作为焊接能量,通过爆炸焊接以及爆炸压接-轧制复合槽型界面金属板的研究思想。爆速是爆炸焊接的重要参数,为配制槽型界面金属板复合专用炸药,研究了玻璃微球尺寸和含量对乳化炸药密度和爆速的影响。结果表明：炸药密度和爆速随着玻璃微球含量增加而减小：小尺寸玻璃微球的敏化效果和调节爆速效果均比大尺寸的好。传统爆炸焊接炸药密度不均,临界直径较大,采用蜂窝铝板作为焊接炸药药框,蜂窝孔的各向约束降低炸药临界厚度的同时,可保证各位置炸药的厚度基本相同,炸药的爆速也有所提高。由于铝合金与钢,尤其镁铝合金与钢界面易产生过熔现象和脆性金属间化合物,难以直接爆炸复合一起,往往需要在铝合金与钢层间加入纯铝、钛等薄板作为中间夹层进行爆炸焊接。为将镁铝合金-钢直接爆炸复合一起,提高界面的结合强度,本文采用5083铝合金与槽型界面Q345钢分别作为覆层和基层,通过公式计算得到铝-钢爆炸焊接窗口后,选取靠近可焊性窗口下限的参数进行实验,再通过力学性能检测和微观形貌观察研究5083/Q345复合板的结合性能。结果表明：铝合金与钢在冶金结合和燕尾槽的挤压啮合共同作用下实现爆炸复合,为铝-钢等强度相差较大的金属材料直接爆炸焊接提供一条新途径：铝合金-槽型界面钢爆炸复合板结合面积比传统铝合金-钢爆炸复合板大145%,铝合金-槽型界面钢爆炸复合板剪切试样强度均大于167.6MPa,满足铝-钢复合板结合强度的要求；5083/Q345复合板界面附近钢侧和铝合金侧显微硬度随着与距离界面的减小而增大,燕尾槽下底面界面5083铝合金和Q345钢的显微硬度与距离燕尾槽上底面界面相同距离5083铝合金和Q345钢的显微硬度基本相等。铝合金与燕尾槽钢上底面、下底面和倾斜面均呈平直状,其中铝合金与燕尾槽钢上底面、下底面以直接结合和不连续熔化块的方式复合,而铝合金与燕尾槽钢倾斜面则以连续熔化层的方式复合：靠近界面Q345钢一侧晶粒呈细长的纤维状,而5083铝合金一侧晶粒未发现拉伸现象；Q345/5083复合板界面中间过渡层生成了脆性金属间化合物FeAl2和Al5Fe2; 5083/Q345复合板拉伸试件断面主要为韧性断裂破坏,并伴有准解理断裂。采用铝-钢爆炸焊接窗口内的参数进行爆炸焊接时,界面金属易产生过熔现象,影响复合板界面的结合性能,而当焊接能量远低于其可焊性窗口下限时,复合板结合强度不高,甚至焊接失效。鉴于不同铝合金与槽型界面钢的爆炸焊接机理相同,采用1060铝和槽型界面Q345钢分别作为覆层和基层,选取低于1060/Q345复合板可焊性窗口下限的焊接参数,仅铝板内表面产生射流,研究槽型界面金属板对铝/钢复合板爆炸焊接窗口的影响。结果表明：铝与槽型界面钢爆炸复合界面结合良好,槽型界面金属板可降低铝-钢爆炸焊接窗口下限；铝与燕尾槽钢上底面以平直状和波状相结合的方式复合,而铝与燕尾槽钢下底面和倾斜面均呈波状结合：界面无金属间化合物生成。传统钛-钢爆炸焊接能量较大,而且钛层厚度较厚时结合率不高,甚至焊接失效,于是提出间隙配合的燕尾槽金属板通过爆炸压接-轧制复合层状金属复合板。本文采用带有燕尾槽的TA2钛板和带有燕尾槽的Q345钢板分别作为覆层和基层,蜂窝结构炸药作为爆炸压接能量,进行钛-钢爆炸压接-轧制复合的研究,然后通过力学性能检测和微观形貌观察分析钛-钢复合板的结合性能,再进行热处理研究退火温度和退火时间对钛-钢复合板界面微观形貌的影响。结果表明：间隙配合的TA2钛板与Q345钢板依靠燕尾槽的挤压啮合以及金属间的相互扩散实现冶金结合：爆炸压接后钛-钢复合板界面未实现冶金结合,界面出现宽5-.45mm的缝隙,爆炸压接-轧制后复合板界面则基本以直接结合的方式复合：钛-钢复合板界面未生成金属间化合物,钢侧晶粒呈细长的纤维状：热处理可消除钛-钢复合板钢侧金属的变形组织,中间过渡层厚度随着退火温度和退火时间的增加而增大：退火温度700℃下保温0.5h得到的钛-钢爆炸压接-轧制复合板界面结合质量良好。
[Abstract]:Explosive welding is a process that utilizes explosive energy to produce plastic flow and metallurgical bonding between high-speed impacting interfacial metals. It has successfully realized the composite of hundreds of metals and is widely used in the preparation of laminated metal composite plates. To the limit of explosive welding window, when the welding energy is small, the interface metal can not produce plastic flow and metal jet, and it is difficult to achieve composite, but when the welding energy is large, it is easy to produce overfusion phenomenon, resulting in the interface bonding strength is not high, and even be stretched open by reflected tensile wave. Detonation velocity is an important parameter in explosive welding. The effect of the size and content of glass microspheres on the density and detonation velocity of emulsion explosive was studied to prepare the special explosive for groove-shaped interface metal plate composite. The density and velocity of explosive decrease with the increase of the content of glass microspheres: the sensitization effect of small size glass microspheres is better than that of large size glass microspheres. It can ensure that the thickness of each explosive is basically the same, and the detonation velocity of the explosive is also improved. Because the interface between aluminum alloy and steel, especially between magnesium and aluminum alloy and steel is prone to overmelting and brittle intermetallic compounds, it is difficult to directly explode and compound together. It is often necessary to add pure aluminum, titanium and other thin plates between aluminum alloy and steel layers as intermediate sandwich for explosion. In order to improve the bonding strength of Mg-Al alloy-steel interface by direct explosive bonding, 5083 aluminum alloy and Q345 steel are used as cladding layer and base layer respectively. After calculating the formula, the parameters close to the lower limit of weldability window are selected for experiment, and then the mechanical properties are tested and measured. The bonding properties of 5083/Q345 composite plate were studied by microscopic observation. The results show that the explosive bonding of aluminum alloy and steel under the combined action of metallurgical bonding and extrusion meshing of dovetail groove provides a new way for direct explosive welding of metal materials with different strength, such as aluminum-steel. The explosive bonding of aluminum alloy-groove interface steel composite plate is a new way. The area of explosive clad aluminum alloy-steel plate is 145% larger than that of traditional aluminum alloy-steel composite plate, and the shear strength of explosive clad aluminum alloy-groove interface steel plate is greater than 167.6 MPa, which meets the requirements of bonding strength of aluminum-steel composite plate. The microhardness of 5083 aluminium alloy and Q345 steel is equal to that of 5083 aluminium alloy and Q345 steel at the same distance from the top and bottom of dovetail groove. Aluminum alloy and dovetail channel steel are combined by continuous melting layer: the grain near the interface of Q345 steel is slender and fibrous, while the grain near the interface of 5083 aluminum alloy is not found tensile phenomenon; the interfacial transition layer of Q345/5083 composite plate produces brittle intermetallic compound FeAl2 and Al5Fe2; 5083/Q345 composite plate is drawn. The fracture surface of the tensile specimens is mainly ductile fracture with quasi-cleavage fracture. When the parameters in the aluminum-steel explosive welding window are used for explosive welding, the interface metals are apt to overmelt, which affects the bonding performance of the composite plate. When the welding energy is far below the lower limit of the weldability window, the bonding strength of the composite plate is not high, even welded. In view of the same mechanism of explosive welding between different aluminum alloys and groove interface steel, 1060 Aluminum and Q345 steel were used as cladding and substrate respectively. The welding parameters below the lower limit of weldability window of 1060/Q345 composite plate were selected. Only the inner surface of aluminum plate produced jet. The explosive welding window of groove interface metal plate to aluminum/steel composite plate was studied. The results show that the explosive bonding between aluminum and groove interface steel is good, the lower limit of aluminum-steel explosive welding window can be reduced by groove interface metal plate; the upper and lower surfaces of aluminum and dovetail groove steel are compounded in a straight and wavy way, while the lower and inclined surfaces of aluminum and dovetail groove steel are wavy bonded: the interface has no intermetallization Compound formation. Traditional titanium-steel explosive welding energy is large, and titanium layer thickness is not high bonding rate, or even welding failure, so put forward gap fit dovetail groove metal plate through explosive Pressing-rolling composite laminated metal plate. This paper uses TA2 titanium plate with dovetail groove and Q345 steel plate with dovetail groove as cladding, respectively. The bonding properties of titanium-steel clad plates were investigated by mechanical properties testing and micro-morphology observation. The effects of annealing temperature and annealing time on the interface micro-morphology of titanium-steel clad plates were investigated by heat treatment. Ming: TA2 titanium plate with clearance fit and Q345 steel plate achieve metallurgical bonding by extrusion meshing of dovetail groove and mutual diffusion between metals: the interface of titanium-steel clad plate is not metallurgical bonding after explosive bonding, and there is a gap of 5-45mm in the interface, while the interface of titanium-steel clad plate is basically in direct bonding after explosive bonding and rolling: titanium-steel clad plate is composed by explosive bonding and rolling. There is no intermetallic compound at the interface of the steel clad plate, and the grain on the steel side is slender and fibrous. Heat treatment can eliminate the deformation structure of the metal on the side of the titanium-steel clad plate. The thickness of the intermediate transition layer increases with the increase of annealing temperature and annealing time. The surface bonding quality is good.
【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG456.6
，
本文编号：2243332
[Abstract]:Explosive welding is a process that utilizes explosive energy to produce plastic flow and metallurgical bonding between high-speed impacting interfacial metals. It has successfully realized the composite of hundreds of metals and is widely used in the preparation of laminated metal composite plates. To the limit of explosive welding window, when the welding energy is small, the interface metal can not produce plastic flow and metal jet, and it is difficult to achieve composite, but when the welding energy is large, it is easy to produce overfusion phenomenon, resulting in the interface bonding strength is not high, and even be stretched open by reflected tensile wave. Detonation velocity is an important parameter in explosive welding. The effect of the size and content of glass microspheres on the density and detonation velocity of emulsion explosive was studied to prepare the special explosive for groove-shaped interface metal plate composite. The density and velocity of explosive decrease with the increase of the content of glass microspheres: the sensitization effect of small size glass microspheres is better than that of large size glass microspheres. It can ensure that the thickness of each explosive is basically the same, and the detonation velocity of the explosive is also improved. Because the interface between aluminum alloy and steel, especially between magnesium and aluminum alloy and steel is prone to overmelting and brittle intermetallic compounds, it is difficult to directly explode and compound together. It is often necessary to add pure aluminum, titanium and other thin plates between aluminum alloy and steel layers as intermediate sandwich for explosion. In order to improve the bonding strength of Mg-Al alloy-steel interface by direct explosive bonding, 5083 aluminum alloy and Q345 steel are used as cladding layer and base layer respectively. After calculating the formula, the parameters close to the lower limit of weldability window are selected for experiment, and then the mechanical properties are tested and measured. The bonding properties of 5083/Q345 composite plate were studied by microscopic observation. The results show that the explosive bonding of aluminum alloy and steel under the combined action of metallurgical bonding and extrusion meshing of dovetail groove provides a new way for direct explosive welding of metal materials with different strength, such as aluminum-steel. The explosive bonding of aluminum alloy-groove interface steel composite plate is a new way. The area of explosive clad aluminum alloy-steel plate is 145% larger than that of traditional aluminum alloy-steel composite plate, and the shear strength of explosive clad aluminum alloy-groove interface steel plate is greater than 167.6 MPa, which meets the requirements of bonding strength of aluminum-steel composite plate. The microhardness of 5083 aluminium alloy and Q345 steel is equal to that of 5083 aluminium alloy and Q345 steel at the same distance from the top and bottom of dovetail groove. Aluminum alloy and dovetail channel steel are combined by continuous melting layer: the grain near the interface of Q345 steel is slender and fibrous, while the grain near the interface of 5083 aluminum alloy is not found tensile phenomenon; the interfacial transition layer of Q345/5083 composite plate produces brittle intermetallic compound FeAl2 and Al5Fe2; 5083/Q345 composite plate is drawn. The fracture surface of the tensile specimens is mainly ductile fracture with quasi-cleavage fracture. When the parameters in the aluminum-steel explosive welding window are used for explosive welding, the interface metals are apt to overmelt, which affects the bonding performance of the composite plate. When the welding energy is far below the lower limit of the weldability window, the bonding strength of the composite plate is not high, even welded. In view of the same mechanism of explosive welding between different aluminum alloys and groove interface steel, 1060 Aluminum and Q345 steel were used as cladding and substrate respectively. The welding parameters below the lower limit of weldability window of 1060/Q345 composite plate were selected. Only the inner surface of aluminum plate produced jet. The explosive welding window of groove interface metal plate to aluminum/steel composite plate was studied. The results show that the explosive bonding between aluminum and groove interface steel is good, the lower limit of aluminum-steel explosive welding window can be reduced by groove interface metal plate; the upper and lower surfaces of aluminum and dovetail groove steel are compounded in a straight and wavy way, while the lower and inclined surfaces of aluminum and dovetail groove steel are wavy bonded: the interface has no intermetallization Compound formation. Traditional titanium-steel explosive welding energy is large, and titanium layer thickness is not high bonding rate, or even welding failure, so put forward gap fit dovetail groove metal plate through explosive Pressing-rolling composite laminated metal plate. This paper uses TA2 titanium plate with dovetail groove and Q345 steel plate with dovetail groove as cladding, respectively. The bonding properties of titanium-steel clad plates were investigated by mechanical properties testing and micro-morphology observation. The effects of annealing temperature and annealing time on the interface micro-morphology of titanium-steel clad plates were investigated by heat treatment. Ming: TA2 titanium plate with clearance fit and Q345 steel plate achieve metallurgical bonding by extrusion meshing of dovetail groove and mutual diffusion between metals: the interface of titanium-steel clad plate is not metallurgical bonding after explosive bonding, and there is a gap of 5-45mm in the interface, while the interface of titanium-steel clad plate is basically in direct bonding after explosive bonding and rolling: titanium-steel clad plate is composed by explosive bonding and rolling. There is no intermetallic compound at the interface of the steel clad plate, and the grain on the steel side is slender and fibrous. Heat treatment can eliminate the deformation structure of the metal on the side of the titanium-steel clad plate. The thickness of the intermediate transition layer increases with the increase of annealing temperature and annealing time. The surface bonding quality is good.
【学位授予单位】：中国科学技术大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG456.6
，
本文编号：2243332
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