Structure and Properties of Explosion-Welded Joints of Carbon Steels

The structure and mechanical properties of bimetallic joints of the same and different types, i.e., iron and steels St3, 45, and 85, are studied after explosion welding and subsequent heating. The cladding and the base layer have a thickness of 2.5 and 12 mm, respectively. It is shown that bending of explosion-welded joints from same-type and different-type steels is accompanied by an anomalous phenomenon of local softening of the near-weld zone in the region of residual deformation with degree ε = 2 – 9%.     

Structure and Properties of Explosion-Welded Composites from Steels of Different Kinds

The structure and mechanical properties of composite materials based on alloy and carbon steels after explosion welding and subsequent heat treatment are studied. The range of heat treatment modes providing high mechanical properties and minimum structural heterogeneity on the layer interface are determined experimentally. It is shown that the diffusion zone forming in heating of composites from steels of different kinds has a well-manifested structure and phase and chemical heterogeneity depending on the mode of heat treatment.     

Peculiarities of phase transitions in polytypes of monoclinic TlInS<Subscript>2</Subscript>

The existence of two polytypes at room temperatures, C-TlInS₂ and 2C-TlInS₂, with different monoclinic cell parameters, c and 2c, has been revealed. Significant differences in crystal lattice dynamics of these polytypes have been found. In particular, two phase transitions (PTs) have been detected for the polytype C-TlInS₂ as the temperature varies: a second-order PT from paraphase to incommensurate phase at T _i = 215 K and a first-order ferroelectric PT accompanied by a quadrupling of the parameter c at T _c = 197 K. No PT accompanied by an increase in unit cell parameter c has been found in the polytype 2C-TlInS₂, but a global temperature hysteresis characteristic of crystals with an incommensurately modulated structure has been detected at T = 180–230 K.     

Effect of the Energy Conditions of Explosion Welding and Subsequent Annealing on the Structure and Hardness of Near-Weld Zone

The structure and mechanical properties after explosion welding and subsequent annealing of bimetallic compounds from dissimilar materials, i.e., armco-iron and steels St3, 45 and 85 with clad and matrix layers 2.5 and 12 mm thick, respectively, are considered