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A new technology has been developed for restoring worn cast iron parts using electric arc surfacing. This technique uniquely combines the simultaneous introduction of filler materials, both as seamless wire and powder alloys, directly into the weld pool. Additionally, oxygen is supplied to the surfacing zone to decarburize the weld pool. The powder alloys used are enriched with graphitizers and carbide-forming elements to protect the melt during the crystallization process. Research has found that the connection zone between the original material and the added layer consistently features a transition layer, regardless of the specific gases and powder materials used. Notably, the use of NPCh‑3 powder, together with the supply of oxygen and carbon dioxide into the weld pool is 2.0–2.7 times thinner than those produced with either PG-12N-01 or PG-10N-04 powders. This method significantly enhances the quality of the deposited layer by increasing the proportion of finely dispersed complex carbides, obtaining an equilibrium structure of fine-plate pearlite with finely dispersed graphite deposits. This results in minimal porosity and the elimination of microcracks, while also reducing cast iron microhardness in the heat-affected zone by 2.1 times. A technology has been developed for restoring cast iron parts through electric arc gas-electric surfacing. This approach has been tested in industrial settings, demonstrating its ability to reduce metal scattering, porosity, and hardness of the deposited layer and the transition zone,. Furthermore, it significantly lowers the likelihood of crack formation, all while minimizing the expenditure on. [ABSTRACT FROM AUTHOR]

The welding materials and processes of fusion welding joint for TA1-X80 explosive composite plate were designed by corresponding welding experiment. Based on the microstructure, composition and properties of the welded joints, a good welding material and process as transition layer for welding titanium-steel composite plate was obtained. The results show that Y-type groove and double-layer transition for metallurgical connection of titanium-steel composite plate are effective. The double-layer consists of nearly titanium layer of Ti-Ni-Al alloy and nearly steel layer of Ni-Cr-Fe alloy. The weld microstructure is changed from coarse equiaxed grain in the titanium layer to fine equiaxed grain or dendrite in the transition layer, and finally is interlaced with the structure of steel. The tensile and yield strength of the welded joint are 501.1MPa and 373.0MPa respectively, which reach the equal match. But the plasticity and toughness are slightly insufficient, which can be improved subsequently by reducing the thickness of the transition layer and adjusting the elements for refining grain size.