No abstract

No abstract

The structure, mechanical properties and impact strength of 5-layered composites based on maraging and low-alloy mild steels are investigated. The effect of subsequent heat treatment on the microstructure and mechanical properties of layered composites is studied. The contribution of the presence of the initial ultrafine-grained microstructure of maraging steel to the formation of the mechanical properties of explosion-welded and thermally strengthened layered composites is evaluated. Kolesnikov A.G., Plokhikh A.I. A study of special features of formation of submicro-and nanosize structure in multilayer materials by the method of hot rolling. Metal Science and Heat Treatment, 2010, vol. 52, iss. 5-6, pp. 44-49 (tekhnologiya, oborudovanie, instrumenty, 2014, no. 3 (64), pp. 28-36. (In Russian).

One of the topical trends in modern materials science is the development and study of new layered metal-polymer composites, which are increasingly used in aerospace engineering, automotive and transport engineering. The metal base of these composites provides a high level of strength properties and impact strength, and the polymer interlayer allows obtaining high damping properties due to its ability to dissipate the energy of elastic vibrations. Of a considerable practical interest is one of the varieties of metal-polymer composite materials based on a sandwich structure -layered steel-rubber composite characterized by pronounced viscoelastic properties, which allows them to be used as vibration damping elements in transport systems. In this work, the possibility of obtaining promising layered metal-rubber composites based on low-carbon steels (Fe-2Mn-1Si steel, IF steel), aluminum alloy Al-Mg3 and heat-and-frost-resistant rubber V-14-1NTA by hot pressing is studied. The influence of the composition and design of composites on the impact strength at temperatures of 20 and −60°C and the damping ability characteristics of materials such as the tangent of the angle of mechanical losses (tg δ), the modulus of elasticity (E ') and the modulus of viscosity (E '') are determined by the method of dynamic mechanical analysis. The possibility of using layered metal-rubber composites with increased resistance to brittle fracture in the region of low climatic temperatures, as well as in structural elements of transport systems with high vibration resistance is shown.

No abstract

No abstract

In the present paper, the microstructure and fracture resistance characteristics of 7-layered composites based on Fe-2Mn-1Si low carbon low alloyed steel and Fe-11Cr-9Ni-2Mo-1Ti maraging steel obtained by two different methods such as explosion welding and hot pack rolling with subsequent heat treatment were investigated. It was shown that an important microstructural features of Fe-2Mn-1Si steel layers are associated with the formation of a fragmentation zone ~10 μm wide with a size of structural elements 0.5-1.0 μm near the interface in the welded composites and the appearance of decarburized ferrite zone ~50 μm wide in the hot-rolled composites. Aсcording to local energy dispersive X-ray microanalysis, at the interface of welded and hot-rolled composites, the most active diffusion processes near of Fe-2Mn-1Si and Fe-11Cr-9Ni-2Mo-1Ti steel interlayer borders occur during the composites production by pack rolling. It was established that explosion welding makes it possible to retain the initial microstructure of steel blanks, with the exception of a narrow near-weld zone of grain fragmentation. After the subsequent heat treatment of explosively welded and hot-rolled composites, Fe-2Mn-1Si steel layers are characterized by a viscous ferrite(sorbitol)-pearlite microstructure, and Fe-11Cr-9Ni-2Mo-1Ti steel layers possess a martensitic microstructure with strengthening intermetallic particles. From the results of impact tests at temperatures from +20°C to −60°C, it was found that the impact strength KCV and energy of impact loading A of the hot-rolled composites are 2 and 3.5 -5.4 times higher than the ones of the welded composites, respectively.

No abstract