COMPARATIVE ANALYSIS OF METHODS FOR DETERMINING THE MASS OF THE SHAFT OF A SPORTS AND AEROBATIC AIRCRAFT, MADE OF TITANIUM AND COMPOSITE MATERIAL

Comparative analysis of an acrobatic aircraft's weight and shaft which is made of a titanium alloy and composite materials. The article contained requirements and specificities of an acrobatic aircraft's landing gear shaft design. The article describes prediction method of an acrobatic aircraft’s weight fraction of shaft which is allows to take into account shaft mass on wing loading upon condition that composite materials will be used in construction. Research objectives include: –Documentation of an acrobatic aircraft’s shaft design. – Analytic dependence conclusions on shaft mass by applying energy absorption of landing impact. – To quantify the algorithm of shaft mass based on strength prediction of shaft construction. –To quantify the mass and construction of shaft based on patterns that are made of titanium and composite materials. – Comparative analysis and references to practical using these methods to quantify shaft’s mass. –To quantify how shaft mass influenced by wing loading. –Designing shaft construction that is made of titanium alloy VT22 and composite material VKU26 by taking into account quantity and ply layup. Comparative analysis shaft mass which is made by different variety of composite materials. The constructive analysis is distinguished for decreasing the shaft mass that is made by composite material and references on ply layup.

Influence of Chemical Composition and Heat Treatment Modes on Mechanical Properties of Titanium Alloy VT22 Bars

The article provides the results of statistical research on the dependence of the mechanical properties of bars with a 14 mm diameter, made of the titanium alloy VT22, on the heat treatment modes and the chemical composition on the basis of the analysis of experimental, literature and manufacturing data. The authors study the correlation between mechanical properties and the content of alloying elements, admixtures, heat treatment modes. The research finds out regression dependences to evaluate the average values of the mechanical properties of the bars 14х14 mm of the alloy VT22 on the annealing temperature (within an hour, furnace cooling up to 4000С, and further air cooling) and the equivalents of alloying elements and admixtures on aluminium and molybdenum.

Effect of Heat Treatment on the Structure and Properties of Titanium Alloy VT22 Welded Joints Produced by TIG-Welding with Flux-Cored Wire

An important part in affecting the properties of the titanium alloy VT22 is a heat treatment (HT). Annealing of welded joints of the alloy also works as strengthening HT. Depending on the heating temperature, duration of annealing and the cooling rate, different combinations of strength and ductility could be obtained. Annealing is carried out in the VT22 alloy two-phase region (750 - 850 °C) followed by direct or stepwise cooling. This heat treatment results in a maximum heterogeneity of the structure with nearly an equal amount of α and β phases. It also provides a tensile strength of 1100 - 1300 MPa.