The Indian government’s policy to encourage local manufacturing in 24 identified sectors (such as aerospace and defense, automotive and auto components, railways, biotechnology, and others) along with new technologies is giving a push for local manufacturing. Additive manufacturing (or 3D printing) is one such technology that is revolutionising manufacturing processes.

Metal 3D printing has benefited significantly from the growing necessity of rapid prototyping and advanced manufacturing practices. With the rapid advancements and perpetual upgrades in software and solutions, AM is keeping up with consumer demands and various industrial needs.

Metal additive manufacturing (metal AM) utilises fine metal powders to construct robust, intricate components through computer-aided design (CAD) programmes or 3D scanning. Laser powder bed fusion, also known as selective laser melting (SLM), is the most stable and reliable metal AM process, which has been around for the longest amount of time. The global metal 3D printing market, valued at $ 6.36 billion in 2022, is expected to expand at a compound annual growth rate (CAGR) of 24.2 per cent from 2023 to 2030, according to Grandview Research. SLM technology led the global metal AM market with 23.77 per cent share in 2022. Although the advantages and ease of operations associated with the SLM technology are encouraging the adoption of this AM method, advances in technology are opening up opportunities for several other efficient and reliable technologies such as selective laser sintering (SLS), direct metal laser sintering (DMLS), inkjet printing, electron beam melting (EBM), laser metal deposition (LMD), laminated object manufacturing (LOM), and electron-beam freeform fabrication (EBF3).

In the traditional subtractive manufacturing processes (such as milling), the scrap rate is as high as up to 80 percent. On the other hand, additive construction – which requires little energy - uses only as much material as is actually needed for the component. The excess powder in AM is also reprocessed.  

Using AM, one can reduce costs for small quantities, complex geometries, materials that are difficult to process or prototypes because 3D printing does not need molds. "Progressive automation brings additional cost savings. Thanks to the so-called "monolithic design", entire assemblies can be printed as one component, whereas employees would otherwise have to manufacture several components individually and then assemble them," opines Sachin Gambhire, Associate Director - Business Development and Marketing, TRUMPF (India).

He adds, “3D printing is particularly advantageous when complex components also need to be given special properties (for example, a prosthesis that is extremely stable but also absorbs shocks). Almost all industries benefit from this freedom in form and function.”

Companies, across all industrial sectors, are recognising the pertinent need for adopting sustainable technology for manufacturing. This has increased market awareness about the need to move away from traditional methods and gradually adopt additive manufacturing. The demand for AM solutions for high-volume production is anticipated to rise as India transforms into a manufacturing hub for large-scale international businesses.

"With additive manufacturing, geometries are possible that conventional processes cannot achieve. This freedom in form and function offers potential for almost all industries. This is why additive manufacturing is both a complementary and a competing technology to conventional metal working technologies and processes," states Gambhire.

According to Dr Vishwas Puttige, CEO, Amace Solutions Pvt Ltd (a part of Ace Micromatic Group that manufactures metal based additive manufacturing machines), AM is a complimentary technology to conventional processes. "The key is to find the right balance between AM and conventional manufacturing to leverage from the best of both worlds and elevate engineering and manufacturing capabilities," he adds.

Today, the technology is getting widely accepted as more than just a manufacturing method for prototyping. In the initial phases of development, the AM industry focused on proving that the technology was competent to manufacture functional components. In the next phase the focus shifted to materials. AM is now being accepted as a technology that can deliver final products which deliver equal, if not better results than their conventionally manufactured counterparts. Parts are now being designed keeping in mind the final functionality rather than the constraints of traditional manufacturing. 

Gambhire states, “We have made massive jumps this year and expect that in 2024 this will continue. Serial production using AM is not a dream anymore, but an everyday reality for us and our customers. Even within TRUMPF, we have 3D printers printing parts for many of our other machine tools."

In India, aerospace and defence sectors have increased AM adoption through their thorough certification processes and validation of repeatability for flight worthy components. The space sector has also embraced the value delivery from this technology and is using it for manufacturing systems which deliver better performance. 

Gambhire explains, “It is now impossible to imagine the aerospace industry without additive manufacturing of series parts. Our customer Airbus, for example, uses additive manufacturing to produce components for passenger planes and helicopters. Tool and mould making also benefits from 3D printing. Designers can rethink the design of components in additive manufacturing and print geometries that cannot be implemented in other ways, such as internal cooling channels for their tools.” 

India's Defense Production and Export Promotion Policy 2020 provided impetus to self-reliance in defense manufacturing under the Aatmanirbhar Bharat scheme. The government aims to achieve a turnover of $ 25 billion (including an export of $5 billion) in the aerospace and defense goods and services by 2025. Experts estimate potential contracts worth $ 57.2 billion for the domestic industry in the next 5–7 years (2025–2027) in the defense sector. This will open up floodgates of opportunities for AM players as the demand for components grow manifold.  

"Laser powder bed fusion as a technology is considered as one of the most industry ready technologies for metal printing due to its ability to print high density and high strength parts making it more suited for end use applications (final products). ISRO, for instance, has been using our machine and technology for printing multiple end use parts for their rockets and satellites. The technology has also found huge application in the healthcare and medical sectors for medical devices and custom implant applications. In addition, we see the die and mould sector using our machines for printing conformally cooled and optimised dies and inserts," opines Dr Vishwas Puttige.

The adoption of additive manufacturing in industries has seen steady growth over the past years. The process has seen some level of standardisation through establishment of manufacturing standards from ASTM, ASME, CEMILAC, etc. The Indian government has also acknowledged the importance of this technology through their National Strategy on Additive Manufacturing, which strives to create a sustainable additive manufacturing eco-system within the country for the domestic as well as the international market. Although AM can be used in almost all industries, the largest user of this technology in India is the aviation, space and defense sectors, closely followed by oil and gas and other industrial applications. 

Gambhire, "For metal 3D printing machines, we observe India is an evolving market as well. The awareness, interest and technology adoption has started picking up the pace recently in the field of metal additive manufacturing. We started offering our TruPrint machines in India just a few years back and have already successfully grown our installed base across India. Our target market segments in India are customers from various industry sectors like medical implants, dentistry, aviation and aerospace, research, tool and die makers and educational institutes etc."

The overall revamp of supply chains globally has increased the importance of decentralised or distributed manufacturing. End users would rather have parts manufactured at a facility close to them rather than a central supplier base. This helps significantly reduce lead times for manufacturing and also enables reduction of cost of storage of inventory through on-demand manufacturing from a set of CAD files and processes set up in a digital inventory. This can be further strengthened by the establishment of data security practices including blockchain.

Mainstreaming of 3D printing, especially metal AM, in the production line is expected to grow and expand in a big way in the near future. "In the last couple of years, we have been seeing big growth in industries such as space and aviation. Now, we are also seeing a steady growth in the medical, dental, tooling and automotive industries. As we have begun to see already this year, consolidation in the AM industry is happening. We believe that this will continue in 2024 with the AM industry maturing," opines Gambhire. 

Additive manufacturing has huge potential in the future. Combining software prowess of AI, Blockchain, etc with new technologies such as multi jet fusion, electron beam melting and fused filament fabrication, AM will continue to make inroads into manufacturing arena of industries. Global uncertainty has forced companies to re-calibrate their sourcing and manufacturing strategies to ensure business continuity even during unforeseen supply chain disruptions. This is providing opportunities for Indian manufacturers to expand their offerings beyond their traditional markets. By adopting new AM technologies, understanding customer's unique requirements and focusing on quality, domestic AM companies can increase their footprint and put India on the global map for additive manufacturing.