Golub D. Improvement of build-up welding technology of die tools by using flux-cored wire

The object of research – Processes of increasing operational stability of die tools by built-up welding of complex-wear-resistant alloy. TThe subject of research – manufacturing technology and composition of the mixture of flux-cored wire, builded-up welding technology and heat treatment for getting of wear resistant bimetallic working build-up overlay of die tool with regulated operational properties. Research methods: study of micro- and macrostructures; mechanical testing of hardness and wear resistance, chemical composition of builted-up metal; mathematical processing of results of studies using multivariate experimental design and statistical methods in Microsoft Excel and StatSoftStatistica. The dissertation is solved to relevant scientific and technical problem task of increasing the operational stability of die tools for cold deformation by improving of manufacturing techniques and composition of flux-cored wire for building up welding complex-wear-resistant alloy, building-up welding technology and heat treatment. The proposed method for manufacturing of flux cored wire, consisting in processing of shell and charge by surfactant additives and application of a magnetic field increases electrical conductivity and uniform melting of wire and reduces force of wire-drawing. Have been further developed scientific and applied course of the creation of complex-alloyed building-up materials, providing reception regulated operational properties of building-up metal based on intermetallic or carbide hardening. Has been optimized composition of tungstenfree wire СПП-100Х4М5Ф2(Zr), providing savings of scarce alloying elements and obtaining toughness 65-75 Дж/см2, hardness 62-63 HRC and wear resistance 2,85-2,9 of die tools. Building up welding and heat treatment of punches by the wire СПП-100Х4М5Ф2(Zr), manufactured on new technology, on optimal regimes, promote to increase in tool life in 1,5-2 times compared with tool from Х12М steel and 3,5-4 times – whith U8A steel. Results of the completed studies and obtained based on these recommendations implemented in a production environment of LTD "Ukrspetsmash" (Berdyansk) with an expected annual economic effect of 98,5 UAH thousand in prices of 2016.