Research Of Explosive Welding For Amorphous Alloys Ribbons

Amorphous alloys have various useful properties such as high strength, soft magnetism and high corrosion resistance. The shapes of these alloys, however, are limited mainly to ribbons, wires, powders, or thin film, because of high quenching rate generally required to preserve the amorphous state from liquid state, This imposed serious limitation on the amorphous state from liquid state and then on the application fields of amorphous alloys. In order to make full use of the potentially useful properties of amorphous alloys and extend the potentially useful properties of amorphous alloys as well as the industrial application, it is very necessary to prepare amorphous alloys in a bulky form. Many research works have been carried out to prepare amorphous alloy compacts. The current researches can be sorted as four aspects, namely, powder metallurgy technique, solid state reaction, making bulk amorphous alloys from melt directly and explosive machining. Bulk amorphous alloys manufactured with explosive welding of explosive machining is researched detailed. It can dispose of the oxide films and the amorphous state of the amorphous ribbons welded can be maintained in bulk samples. Research products worked out are as follows:1. "Foils academic explosive welding window" is put forward based on the particularity of explosive welding for multi-layer amorphous ribbons. Welding upper limit, down limit and flow limit are qualified newly.2. Macroscopical and microcosmic cracks appear in bulk amorphous alloys produced by explosive welding some times. To prevent it, strain rate and strain near explosive welding interface must be researched. In this paper, an ideal fluid model of symmetrically colliding is taken to analyze the distribution rule of strain rate and strain on streamline. Points position for maximum equivalent strain rate are found out, It is useful for analyzing adiabatic shear bands(ASB). Whole strain distribution rules with same colliding speed, different explosive speed are calculated.3. Temperature rising near explosive welding interface is caused by explosive adiabatic compression of temperature and sedimentary abnormality deformation energy. Throughcalculation of temperature rising callused by them, melt criterion is given, the thickness of melted layer near explosive welding interface with small collision angle is estimated.4. Based on analysis of characters of amorphous alloys producing and heat exchange during explosive welding ,a square wave model for the temperature field across the interface during explosive welding for multi-layer foils has been proposed. The model can be used to analyze the reason of amorphous state kept across the interface after explosive welding, and results accord with the matters of fact very well.5. Explosive welding of amorphous alloys with 20~120 layers. 25um thickness hasbeen carried out. Amorphous alloys board and tube are explosive welded well. At the same time, single layer amorphous alloys can been welded on general steel well.