No abstract

В жаропрочных никелевых сплавах, применяемых для производства лопаток турбин газотурбинных двигателей, фазовая стабильность частиц g ¢ фазы при повышенной температуре в процессе эксплуатации непосредственно определяет деградацию прочностных характеристик металла. С целью контроля остаточной долговечности лопаток турбин, выполненных из жаропрочных никелевых сплавов с различным процентным содержанием таких легирующих элементов как вольфрам (W) и молибден (Mo), было проведено исследование изменения микроструктуры сплавов, имеющих различные соотношения Mo и W при различных температурах и времени выдержки. Экспериментальные результаты показали, что скорость укрупнения частиц g ¢ фазы возрастает с увеличением соотношения Mo/W.

In the current global economic conditions, airlines need to curtail financial expenses. It is known that the share of airline costs for maintenance and repair (MR) in the total cost structure amounts to at least 20%, of which more than 40% is for the repair and maintenance of aircraft engines (AE). According to the actual expertise, this item of expenditure will continue to grow due to the inevitable sophistication of AE structures, which is specified by the need to increase the efficiency and ecological compatibility. One of the possible ways of curbing maintenance and repair expenses is to transit for the operation of on-condition components which are currently in operation until the overhaul life is exhausted. For example, turbine blades of gas turbine engines (GTE) can be pertinent to such elements. It is a common fact that turbine blades operate in challenging environment: they are affected by excessive temperatures, severe centrifugal loads, aggressive gas media, and their destruction generally occurs because of the accumulation of fatigue damage and creep. The alloy microstructure significantly degrades and deforms before macroscopic damage develops. The early detection of microscopic damage in the alloy is the tool which allows for the transition to GTE oncondition turbine blades operation. The article presents the method for calculating the minimum creep rate of the Inconel 738LC alloy based on microstructural changes under operating conditions. The obtained results are proposed to be used for calculating the residual life of turbine blades by the creep parameter.

A calculation methodology for estimating the residual life of a high-pressure turbine blade based on the taking into account of the morphological state of dispersion-strengthened material is proposed. A good convergence of the calculation results with the experimental data is shown.