Study on the Effects of Explosive Covering on Explosive Welding of Stainless Steel to Steel

Abstract

In order to improve the energy utilization ratio of explosives and reduce the noise and dust for explosive welding, honeycomb structure explosives covered by colloid water were put forward as explosive materials. Using 304 stainless steel and Q235 steel as flyer plate and base plate respectively, explosive welding tests were carried out with different covering thicknesses. The dynamic parameters in the collision process were obtained by experimental measurement and theoretical calculation. The microstructure of the bonding interface was observed through optical microscopy and analyzed by welding window. The results showed that, compared to the explosive welding without covering, the impact velocity of flyer plates was increased by 38.9 %, 57.5 % and 71.9 % respectively when the covering thickness was 15 mm, 30 mm and 45 mm. The impact velocity predicted by Gurney formulas was significantly larger than the measured value, however, after considering acceleration history, the calculated value was in good agreement with the experimental result. Metallographic analysis showed that wave bonding interfaces without defects such as voids and cracks were obtained when the welding conditions were within the welding window. However, voids and cracks were found at the bonding interfaces when the welding conditions were close and above to the upper limit of the welding window.

Application of Colloid Water Covering on Explosive Welding of AA1060 Foil to Q235 Steel Plate

“…This indicates that the consumption of explosives is reduced by 25.4 %. According to the Gurney equation [22], the calculated value of impact velocity is 446 m/s and 501 m/s for the new and conventional method, indicating that this method can effectively reduce the excess energy. Also, there are some poor bonding zones near the boundary.…”

“…The colloidal water was composed of 1 % Super Absorbent Polymer (SAP) and 99 % water, with a density of 0.97 g/cm 3 . The colloidal water is granular and behaves as a solid, it is easy to precisely control the covering thickness and make water repellent treatment for some explosives with poor water resistance (the loss of sensitivity or reduction of detonation performance of some explosives when exposed to water) [22]. The flyer and base plates used in this study were made of AA1060 foil and Q235 steel plate, the dimensions of which were 0.2 mm × 80 mm × 150 mm and 20 mm × 100 mm × 200 mm, respectively.…”

“…In our previous work , a novel charging structure, honeycomb structure explosives covered by colloid water, was presented to improve the energy utilization ratio of explosive welding. Based on this, the goal of this work is applicating this charging structure to weld foil.…”

Study on explosive welding of Cu/steel composite pipe under local water environment

“…An explosive detonation velocity between 2000 m/s-3000 m/s is frequently used to weld copper and steel, too high or too low detonation velocity will lead to poor welding quality [10]. Here we choose diatomaceous silica-sensitized emulsion explosives whose density and detonation velocity is about 0.7 g/cm 3 and 2327 m/s respectively. The specific parameters of explosives have been discussed in detail by Sun [11], and the chemical composition of the emulsified matrix is listed in Table 3 [11].…”

“…[2] proposed a six‐layer explosive welding device, which can simultaneously obtains three sets of composite metal plates, and effectively improves the production efficiency; Yang et al . [3] used colloidal water coating to constrain the explosive, which improves the utilization rate of the explosive and increases the explosive detonation velocity by nearly 57 %; KAZUYUKI et al . [4] used an underwater shock wave to carry out large‐scale explosive welding, and pointed out that under this condition, explosive welding is still feasible even without a separation distance between plates; Liu et al .…”