Overview
Researchers at the ARCI, Hyderabad have created a crack‑free bi‑metallic component by using laser‑based powder bed fusion. The component joins stainless steel SS316L with nickel‑based superalloy IN718. This development can cut India’s reliance on imported super‑alloys.
Key Developments
- Direct additive manufacturing of SS316L onto a ground IN718 plate without visible cracks or porosity.
- Peak micro‑hardness of ~310 HV at the interface and ultimate tensile strength of 550 ± 30 MPa, with failure occurring in the softer steel side, confirming strong bonding.
- Potential to place expensive super‑alloy material only where high‑temperature resistance is needed, reducing overall material cost.
Important Facts
The research, published in Progress in Additive Manufacturing, was led by S. Narayanaswamy, Gururaj Telasang, Nokeun Park and Ravi Bathe. The bi‑metallic structure can be used in:
- Boiler tubes and heat exchangers for nuclear and ultra‑supercritical (USC) coal‑fired power plants.
- Advanced energy systems where different zones face varying temperatures and stresses.
- Aerospace components – steel side for load‑bearing, Inconel side for thermal protection.
- Nuclear reactors and oil‑and‑gas processing units requiring both corrosion resistance and high‑temperature strength.
Exam Relevance
This breakthrough touches several GS papers:
- GS3 – Technology & Economic Development: Shows how indigenous additive manufacturing can reduce import dependence on critical materials.
- GS3 – Energy Security: Enhances performance of power‑plant components, supporting India’s goal of expanding ultra‑supercritical coal and nuclear capacity.
- GS3 – Industrial Policy: Aligns with the DST agenda of self‑reliance in high‑tech sectors.
Way Forward
To translate this lab success into industry:
- Scale up the process in collaboration with aerospace and power‑generation firms.
- Formulate standards for bi‑metallic additive‑manufactured components.
- Encourage public‑private partnerships under the Make in India framework.
- Invest in training engineers on powder metallurgy and laser‑based fusion technologies.
Successful adoption can lower the cost of critical super‑alloys, boost indigenous manufacturing, and strengthen India’s strategic capabilities in energy and defence sectors.