Indigenous Titanium Sponge Plant at Chavara, Kollam has been fully commissioned and started commercial production of Titanium sponge required for Space applications
Titanium (Ti) alloy products find extensive applications in Aerospace and Defence areas. Properties like high strength to weight ratio and excellent corrosion resistance make Titanium alloys (like Ti6Al4V) useful for liquid propellant tanks for launch vehicles and satellites, gas bottle/liners, inter tank structures and interface rings for satellites. Realisation of Titanium alloy wrought products and fabrication of hardware are carried indigenously. However, the raw material for aerospace grade Titanium alloys with high purity Titanium sponge (min. 99.7% Titanium) was being imported from countries like Russia, Japan and China despite the fact that India is endowed with the third largest reserve of Titanium bearing minerals.
ISRO took the initiative to set up a Titanium Sponge Plant (TSP) in the country to meet the requirements in strategic areas. The annual requirement of Titanium sponge for space programme is approx. 200 – 300 Metric Tonnes (MT). ISRO’s Vikram Sarabhai Space Centre (VSSC) has established a dedicated 500 MT per annum plant at M/s Kerala Minerals and Metals Ltd (KMML), Chavara, Kollam. The plant is set up with necessary infrastructure to enhance the production capacity to 1000 Tonnes Per Annum (TPA) in future. This is the only integrated plant in the world that undertakes all activities right from mining of Ti minerals to the manufacturing of aerospace grade Ti sponge under one roof.
The plant is fully commissioned and has started commercial production of Titanium sponge required for Space and Defence applications. With this, India has become the seventh country in the world producing Titanium sponge commercially. Approximately 350 MT Ti sponge has been realised till date with nearly 70% yield of aerospace grade (>99.7% purity). Analysis of the results shows that the sponge produced is of superior quality.
In order to qualify the sponge for space applications, VSSC has realised aerospace grade Titanium alloy Ti6Al4V products at Midhani, Hyderabad through double vacuum arc re-melting route followed by rolling/forging and heat treatment into wrought products in annealed condition and extensive qualification tests have been performed on the material.
Hemispherical domes were made from Ti6Al4V plates through hot forming process at BrahMos, Thiruvananthapuram. These domes are further machined and joined by electron beam welding to gas bottles. Two numbers of such 600 mm diameter gas bottles required for PS2/GS2/L-110 stage pressurisation systems for a rated capacity of 330 bar were realised and qualified. These are used in PSLV, GSLV and GSLV Mk III launch vehicles. All the bottles were subjected to proof pressure testing at 495 bar and accepted. One of the gas bottles was subjected to burst test and the gas bottle withstood 700 bar pressure against 660 bar requirement.
With this, indigenous Ti sponge is completely qualified for space applications giving a big boost to Make in India campaign.
