Mathematical Modeling and Analysis of Thermostressed State of Bimetallic Plate Under Electromagnetic Action in the Mode with Pulse Modulated Signal

The thermostressed state of a bimetallic plate under the electromagnetic action in the mode with pulse modulated signal (MPMS) at the resonant frequencies of the electromagnetic field is studied. There are established the critical values of the parameters of the electromagnetic action at which the bimetallic plate loses its load-carrying ability as a constituent element.

Диагностика остаточных напряжений в биметаллических пластинах алюминий-сталь с использованием лазерного ультразвука и зондирующего отверстия

The character of changes in laser photoacoustic signals near small-diameter holes in layers of aluminum and steel in a bimetallic plate obtained by hot rolling is investigated. The experimental results are compared with the solution of the classical Kirsch problem for stress distribution around a circular hole in a prestressed material. The possibility of assessing internal stresses by a laser photoacoustics in combination with the hole drilling method in industrial bimetallic plates is shown.

Interface Microstructure and Thermal Expansion Mismatch in Alloy N/316H Bimetallic Plates

Two Alloy N/316H bimetallic plates have been fabricated by explosive welding and rolling technologies respectively. Metallographic observations indicate that the rolled bimetallic plate has a straight bond interface, in which some cavities and precipitates exist. While the explosive welded plate shows a wavy bond interfaces. The interface thermal expansion mismatch between the two alloys were evaluated in the two plates at high temperature. Results show that the thermal expansion coefficient of 316H is larger than that of Alloy N. The thermal expansion coefficient of the substrate plates depends on the thickness ratio between Alloy N and 316H, which reaches the maximum when the ratio is 1:4.

Implementation of Megaplastic Deformation for Control of the Gradient Composition of Pseudo-Layers in the Nitrided Surface of Fe-Ni-Cr Steel - Production of Quasi-Bimetallic Plate

Megaplastic deformation has been realized by sliding friction (or high-pressure torsion) on ion-plasma-nitrided surface of austenitic Fe-Cr-Ni steel. The deformation-induced dissolution of iron and chromium nitrides, the formation of secondary chromium nitride phases and the increase of depth of gradient-composition matrix pseudo-layer have been achieved under friction and subsequent annealing. A quasi-bimetallic foil with the largest dimension of deflection has been produced with the use of friction and subsequent annealing of the nitrided surface.