Havrysh P. Scientific bases of development theory and practice of the technology welding copper with steel

Object of study: weld procedure of heterogeneous metals. Subject of research: thermodynamical and technological coordinates of the process of welding copper with steel. Research methods: thermodynamic researches, mathematical modeling, strain-measuring researches of the power parameters of drawing a powder wire, mechanical test, research micro and macrostructures of welded joints. In the thesis original positions of process the formation of structures metal melts copper with steel are evidence-based and specified. The key thermodynamical coordinates of process the crystallization of melt the copper and steel it are specified allowed to simulate the course of process in welding environments when developing new welding materials. The expediency of the use postwelding processing of a welded joint is evidence-based by method of the local plastic strain (rolling), what provided increase in ultimate strength of a joint weld "copper/steel" for 33%. For the purpose of the decrease cavitation in a joint weld for the first time it is offered to use preliminary pulse heating when welding copper with steel also its optimum mode is defined: duration of an impulse current – 10 ms; density –103 А/ mm2. Economic effect from applying of the work results of is more 500 Thous.UAH.