Construction and experimental investigation of the R-δ_f-type welding window

In this study,a new R-δ_f-type welding window on charge parameters is constructed by determining the boundary conditions of the explosive ratio.The R-δ_f-type welding window synthetically considers the explosive properties and material properties,and can quickly determine the explosive charge at different welding materials with different thickness.In order to test the practicability and accuracy of the R-δ_f-type welding window,410 S stainless steel and QSA5 R low alloy steel plates were explosively welded using 15 mm charge determined by the new window.Microstructures of the bonded sections were examined and then shear tests were carried out on the bonded specimens.Microstructural examination showed the joint interface was transformed from micro wavy to small wavy appearance without microstructure defects.Shear tests results showed interfacial shear strength was much higher than that of the national first grade standard.So the R-Sj-type welding window has strong practicability and accuracy and is helpful to the practical production and application of explosive welding composite materials.     

双立式爆炸焊接R-δ型可焊性窗口

针对双立式爆炸焊接新方法的爆轰驱动特点,通过研究双立式爆炸焊接条件下的焊接下限、焊接上限、临界起爆厚度、临界碰撞角和临界复板厚度等可焊性边界条件,构建了一种静态参数下的双立式爆炸焊接R-δ型可焊性窗口;该窗口综合反映了爆炸焊接中的复板特性和炸药特性两大焊接参数,所建立的铜、不锈钢、铝合金等材料的双立式爆炸焊接R-δ型可焊性窗口可直接运用于工程实践中;根据双立式爆炸焊接R-δ型可焊性窗口设置的15 mm超低药量试验下的304L/Q235b复合板实现了高质量的微小波状结合,说明该窗口可以作为确定双立式爆炸焊接工艺参数的依据.     

钛/钢双立式爆炸焊接参数优化

为解决大面积钛/钢爆炸焊接窗口窄,在结合区易出现"过熔"和"射流堆积"等微观缺陷的问题,开展了双立爆炸+轧制综合制造技术,进行了低爆速爆炸焊接用炸药试验优化,发明了一种最低临界爆速爆炸焊接用炸药,设计确定了刚性防护板和柔性防护墙构成的双立综合防护结构及参数,研究了钛/钢爆炸焊接装药厚度窗口.结果表明,双立钛/钢复合板结合界面成波状结合,几乎不存在金属熔化、漩涡等微观缺陷.     

爆炸焊接最小作用量原理分析

最小作用量原理是自然界的一条基本法则,也是物理学的最后规律.通过爆炸焊接的理论分析、界面测试和生产实践发现,爆炸焊接过程也遵循物理学"最小作用量原理",即以最小的装药量获得最佳的焊接界面.在复板和基板发生非弹性碰撞直至结合这一力学过程中,其"作用量"可认为是"复板和基板的结合能量".为了使界面结合能量为最小,在选取爆炸焊接工艺参数时,需遵循"装药厚度下限法则"和"基复板间隙上限法则"等原则,并优选"最低临界爆炸速度炸药",即可实现爆炸焊接过程"最小作用量原理",从而使爆炸焊接界面状态达到最佳.     

Design and test of a protective structure for the double vertical explosive welding of large titanium/steel plate

A comprehensive protective structure with rigidity and flexibility was put forward and designed in view of the quality and safety problems for the double vertical explosive welding of large titanium/steel cladding plate. The movement speed and displacement of the protective structure was calculated by establishing its physics model. The dynamics and stabilization properties were analyzed, and the protective structure parameters were optimized and devised. The comprehensive protective structure, which is composed of rigidity unit and flexibility wall, can bear the impact of detonation wave and the high-speed movement of the cladding plate. There are no damage and deformation in the protective structure and the cladding plate. The protective structure can be used many times. The bonding rate of the Ti/steel plate obtained was nearly 100%, and there is no deformation, surface cracks, and big wave and micro-defects. Therefore, the protective problems of the double vertical explosive welding can be solved effectively by the protective structure.     

Experiment and interface of Ti/Q235B cladding plate by double vertical explosive welding*

The processing area is reduced by double vertical explosive welding and rolling.Those micro defects are avoided such as"fusion"and"jet pile"in the bonding zone of large Ti plate of explosive welding.So the quality and welding ratio of interface are improved.To solve the technical problem of narrow weldability window of Ti,a minimum critical detonation velocity explosive was invented to enlarge the window after double vertical explosive welding experiment and optimization.A comprehensive protective structure made up of rigid protective plates and flexible protective walls was designed to restrict the movement of cladding plates in double vertical explosive welding effectively and protect the cladding plates from damage.The interface microstructure showed that the bonding interfaces were periodically micro and small wavy and there are no micro defects such as melt metal and swirl.