Rajnath Singh congratulates DRDO on developing single crystal blades for helicopter engine application
Apr 26, 2021
New Delhi [India], April 26 : The Defence Research and Development Organisation (DRDO) has developed a single crystal blades technology and has supplied 60 number of these blades to Hindustan Aeronautics Limited (HAL) as part of their indigenous helicopter development program for helicopter engine application.
The supply of the remaining four sets will be completed in due course.
According to Ministry of Defence, this is part of a program taken up by Defence Metallurgical Research Laboratory (DMRL), a premium laboratory of DRDO to develop 5 sets (300 Numbers) of single crystal high pressure turbine (HPT) blades using a nickel-based super alloy. The supply of the remaining 4 sets will be completed in due course.
Meanwhile, Defence Minister Rajnath Singh congratulated the DRDO. "Raksha Mantri Rajnath Singh has congratulated DRDO, HAL and the industry involved in the development of this critical technology," his office tweeted.
The DRDO said that helicopters used in strategic and defence applications need compact and powerful aero-engines for their reliable operation at extreme conditions. To achieve this, state-of-the-art single crystal blades having complex shape and geometry, manufactured out of Nickel based superalloys capable of withstanding high temperatures of operation are used. Very few countries in the world such as the USA, the UK, France, Russia, have the capability to design and manufacture such Single Crystal (SX) components.
DMRL undertook this task based on its expertise gained during the development of such a technology for an aero-engine project earlier. Complete vacuum investment casting process to realise the blades, including die design, wax pattering, ceramic moulding, actual casting of components non-destructive evaluation (NDE), heat treatment and dimensional measurement, has been established at DMRL.
"Special ceramic composition had to be formulated for making strong ceramic moulds which can withstand metallostatic pressure of liquid CMSX-4 alloy at 1500 degree Celsius and above during casting operation. The challenge of maintaining the required temperature gradient has also been overcome by optimising the casting parameters. A multi-step vacuum solutionising heat treatment schedule for complex CMSX-4 superalloy to achieve the required microstructure and mechanical properties has also been established," the Ministry said.
Further, a stringent non-destructive evaluation (NDE) methodology for the blades along with the technique for determining their crystallographic orientations has been developed.
