ПРИМЕНЕНИЕ ЛАЗЕРНОЙ ИМПУЛЬСНОЙ НАПЛАВКИ ПРИ РАЗРАБОТКЕ ТЕХНОЛОГИИ ВОССТАНОВЛЕНИЯ РАБОЧИХ ЛОПАТОК ТУРБИНЫ ГАЗОТУРБИННОГО ДВИГАТЕЛЯ

摘要

Рассматривается возможность использования высокотемпературных порошковых припоев в качестве износостойких слоев, наносимых посредством лазерной импульсной наплавки, как альтернатива классическим износостойким композитам с примесью карбида вольфрама. Данные материалы апробируются для последующего восстановления высоты пера лопатки турбостартера турбовинтового авиационного двигателя НК-12МП и придания торцевой кромке износостойких свойств. На основе проведенных сравнительных исследований на электронном микроскопе и микротвердомере, испытаний на локальный абразивный износ и анализа различных порошковых материалов (ВПр11-40Н, ВПр24, ВПр27, Рок-Дюр 6740) при импульсной лазерной порошковой наплавке подтверждена пригодность некоторых порошковых припоев в качестве износостойких слоев при восстановление контактных поверхностей лопаток турбины.%The gas turbine engine advancement goes hand in hand with the development of its basic component, namely, gas turbine as the key source of efficiency enhancement of the engine in aggregate. With each turn of gas turbine development, materials and technologies used for its manufacturing became more and more complicated and, as a consequence, expensive. Russia is one of global manufacturers of gas turbine engines.rnThe cost of engines for aviation and power industry applications is considerably high. Thus, on this background its reduction remains the main criterion of manufacturer's competiveness on the market. Besides, we should bear in mind that the gas turbine engines maintenance costs in the course of the engine life might exceed its original cost. Without effective maintenance technologies, manufacturing would incur permanent losses. One of the basic specifics of gas turbine engines consists in their significantly high production costs of a number of their parts and subassemblies with relatively short lifetime, requiring permanent replacement. Rotor blades present precisely these parts. They can be damaged by a great number of factors from changes in the structure to loss of geometry. The latter is the most frequent factor even in the case of insignificant geometry loss. From the maintenance technologies viewpoint turbine blades restoration is the most cost-effective, compared to the other parts of the engine. But the complexity of this task remains the major obstacle to its realization.rnThis article discusses the possibility of using high-temperature solder powders as wear-resistant layers applied by laser pulse buildup, as an alternative to classic wear-resistant composites with tungsten carbide admixture. These materials are undergoing testing for further pen height recovery on the example of the turbine blade of the turboprop starter for NK-12MP aircraft engine, and attaching wear-resistant to its end edge.rnBased on the conducted studies with Tescan VEGA3 LM electron microscope and Hardness DuraScan-10 micro-hardness meter, together with local abrasive wear tests and various powder materials, such as VPr11-40N, VPr24, VPr27 Rock-Dur 6740, analysis while pulse laser powder buildup, the authors confirmed the applicability of several solder powders as wear-resistant layers for turbine blades contact surfaces recovery. Further, comparative studies of the basic material, soldered and built-up structures of VPr11-40N (having the best figures) solder were conducted to detect hardening wear-resistant phases. The cooling rate dependencies of shaping and VPr11-40N solder strengthening phase size were revealed.