The paper is devoted to the analysis of the issues connected with crystallisation of multicomponent bronze during centrifugal casting. Bronze containing tin, lead, zink, nickel, copper has been chosen as a material for study. In the course of the study the spin rate of the mould has been varied. The researches of the structure have shown that during solidification of the cast the quantity of lead increases from the middle part to the inner one, and for high spin rates the difference in lead content in different cross sections of the casting being less noticeable than in case of the low ones. In addition it has been noted that great spin rates of the mould reduce liquating processes and provide a more homogenuous structure of casts.

In this study, the weldability of thick dissimilar steels to a thin-wall pipe using the electron beam welding has been investigated. In addition, weld quality evaluation in as-welded condition has been conducted. For this purpose, micro and macro examination of the welds has been carried out.

The paper is devoted to the study of the multicomponent lead-tin bronzes. The data on the influence of rotational velocity of a casting mould and the temperature of melt pouring on the structure and mechanical properties are presented in the article. The results of mechanical tests and studies of the microstructure allowed determining the optimal conditions of obtaining the castings with high strength characteristics. The conducted researches show that the maximum values of strength (σV=280–290 MPa) and impact strength (КС=2.7–3.2 KJ/cm2) are provided at the pouring temperature of 1150–1200 ̊С and rotational velocity of a casting mould equal to 1200 rpm.

This work presents the characteristic properties of powdered materials sintering under conditions of liquid-phase sintering. It has been established that to implement the liquid-phase sintering advantages it is necessary to do temperature research when the liquid-phase concentration does not exceed the critical one. The implementation of this condition provides the sintering temperature reduction by 150 – 200 °С.

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