Read all the biggest 3D printing stories of 2024 in the 3D Printing Industry Review of the Year.In April, business news continued to dominate the headlines. Two of the most influential additive manufacturing consultancies published annual market reports highlighting key industry trends, analysis, and forecasts for the future of 3D printing. Notably, the reports featured starkly contrasting 3D printing market size estimations.Elsewhere, GE Aerospace debuted as an independent company on the New York Stock Exchange following General Electrics restructuring. Solidscape also went solo after a private investor acquisition, while Markforged was ordered to pay $17.34 million in a patent-infringement lawsuit.Sustainability was another key theme in April, with several companies announcing eco-friendly additive manufacturing initiatives. Additionally, the focus on strengthening domestic supply chains in the US continued with efforts to re-shore the production of batteries and missiles. Medical applications were also spotlighted, with one research institute 3D printing ultra-realistic heart and lung models.Read on for 3D printing updates from Stratasys, MIT, Ursa Major, 6K Energy, Farsoon Technologies, Meltio, AML3D, and more.Larry Culp, CEO of GE Aerospace, and Scott Strazik, CEO of GE Vernova ring the Opening Bell. Photo via GE Aerospace.What is the 3D printing market size?In April, Wohlers Associates, the Colorado-based additive manufacturing consultancy firm operating under ASTM International, released its Wohlers Report 2024. This outlined that the industry had grown 11.1% to a 3D printing market valuation of $20.035 billion, exceeding $20 billion for the first time.The reports principal author, Terry Wohlers, told 3D Printing Industry that the market size is actually much larger than what we report. He explained that the estimate excludes capital spent on 3D printing within organizations like Adidas, NASA, and Stryker. The figure also omits the value of research, development, prototyping, tooling, and parts 3D printed by original equipment manufacturers.Looking to the future of 3D printing, the report anticipates a shift to the high-volume production of end-use parts. Wohlers predicts that production will move from thousands of parts to hundreds of thousands. Million-part production runs are also anticipated for small components.German consultancy AMPOWER reported a 3D printing market size of just 10.5 million for 2023, approximately half of the Wohlers figure. This estimate, published in the AMPOWER 2024 report, represents a 10.3% increase compared to the previous years estimation. Metal powder bed fusion 3D printers reportedly accounted for 40% of sales 2023 revenue. Additionally, robust growth was seen in the aerospace and defense sectors, with a 30% increase over the past two years. The rise in global defense budgets is expected to drive the adoption of additive manufacturing further. However, the automotive sectors investment in 3D printing stagnated in 2023, while startup funding declined due to a lack of global venture capital.AMPOWER projected steady industry growth, forecasting an annual growth rate of 13.9% and 20 billion in revenues by 2028. Equipment suppliers in the Asia-Pacific (APAC) region are expected to experience an annual growth rate of around 16% until 2028.Wohlers Report 2024 data shows increasing metal 3D printer sales. Image via Wohlers Associates.3D printing business updates April saw GE Aerospace debut on the New York Stock Exchange as an independent public company following GEs operational restructuring. This resulted in the creation of three independent companies: GE HealthCare, GE Vernova, and GE Aerospace. Metal 3D printer manufacturer Colibrium Additive, rebranded from GE Additive, is part of GE Aerospaces Propulsion & Additive Technologies (PAT) division.A joint opening bell ceremony alongside GE Vernova was held on April 2, 2024. The aerospace manufacturer entered the market with a sizeable installed base, including 44,000 commercial engines and 26,000 military engines worldwide.GE Aerospaces hypersonic dual-mode ramjet engine. Photo via GE Aerospace.Another company that announced its independence was high-resolution 3D printing specialist Solidscape. Known for its 3D printers for the jewelry and precision investment casting industries, the company was acquired by a private investor. This formed part of a strategic move to reinforce Solidscapes presence and innovation in the jewelry 3D printing market.This announcement followed the news in January that Prodways had discontinued the Solidscape product line of wax and resin 3D printers, which had performed poorly in 2023. Following the acquisition, Solidscape will continue to offer its range of 3D printers and materials for jewelry applications. The company also confirmed its commitment to developing new products and improving existing technologies.A 3D printed ring model and the final part. Photo via Solidscape.Elsewhere, Canadian 3D printing powder developer Equispheres raised approximately CAD 20 million in a Series B funding round. Martinrea International led the round, while INFOR Financial and Stifel Nicolaus Canada acted as financial advisors. The company planned to leverage this capital across various critical efforts, including new reactors to scale its production capabilities.In legal news, 3D printer manufacturer Markforged was ordered to pay Continuous Composites $17.34 million as part of a patent infringement lawsuit that began in 2021. A federal jury in the US District Court for the District of Delaware found that several of the companys 3D printers infringed on a patent covering the method and apparatus for continuous composite 3D printing. In a statement, Markeforged commented that it strongly disagrees with this verdict and outlined intentions to overturn the verdict in post-trial motions.Later this year, Markforged settled with Continuous Composites after agreeing to pay the company $25 million. The deal, which included a Patent License Agreement, resolved all claims and counterclaims in the IP dispute.Markforged HQ. Photo via Businesswire.Sustainable manufacturing initiativesThe sustainability of additive manufacturing was a key talking point in April. The month saw leading 3D printer manufacturer Stratasys publish its second environmental, social, governance, and sustainability report. This highlighted the environmental sustainability and social impact of the companys 3D printing technology.Stratasys stated that it is delivering on the mindful manufacturing commitments it made in its 2022 report, claiming its technology enables manufacturers to transition to more sustainable practices. The company also highlighted several environmental, social, and governance-based achievements.Most impressively, Stratasys announced it reduced 207 metric tons of CO2 emission by adopting renewable energy at its facilities. The company installed solar panels at its Israel facilities, generating 441,339 kWh of renewable energy. It also claimed to have reduced 3D printing waste through its recycling program. This increased the number of recycled filament spools, cartridges, and canisters by 11.3%.Rooftop solar installation at Stratasys Kiryat Gat Manufacturing installation. Photo via Stratasys.Later in the month, a team from the Massachusetts Institute of Technology (MIT) developed an FDM 3D printer that can autonomously create parameters for unknown materials. This system seeks to increase the adoption of unique 3D printing filaments that are more sustainable than hard-to-recycle, fossil fuel-based polymers.Also targeting recycling was UK-based 3D printing filament manufacturer Filamentive, which introduced its free 3D Printing material recycling service. Said to be the first scheme of its kind in the UK, it allows existing Filamentive customers to return their PLA waste free of charge. 100% of this material is then recycled into new products.The company hopes this will combat increasing 3D printing-related plastic pollution. According to Filamentive, 33% of 3D printed parts end up as waste, translating to 400,000 kg of plastic in the UK each yearOn the powder side, the AMGTA published the results of its study on the most sustainable metal 3D printing materials. The findings suggest that helium gas atomization is the most energy-efficient method for producing common metal powders. This reportedly uses 13% less energy per kilogram of powder compared to argon and 28% less than nitrogen for common alloys.Filamentive PLA recycling box. Image via Filamentive.Re-shoring manufacturing in the USIn April, efforts to re-shore manufacturing in the US ramped up. Within the defense sector, rocket engine manufacturer Ursa Major signed a contract with the US Navy to design and test a 3D printed solid rocket motor (SRM) for the Standard Missile program.This agreement sees the company leverage its additive manufacturing-based Lynx technology to design the next generation of SRMs optimized for reliability and manufacturability.The project aims to create a new 3D printable design for the Mk 104 dual rocket motor, addressing challenges associated with traditional manufacturing methods. The Mk 104 powers the SM-2, SM-3, and SM-6 missiles. This year, demand for missiles in America surged due to a shortage of domestic suppliers, the need to replenish US stockpiles, and ongoing support for Ukraines war efforts.Also in April, a large-scale ARCEMY X-Edition 6700 3D printer from AML3D became fully operational at the US Navys Additive Manufacturing Center of Excellence in Danville, Virginia. Worth AUD$1.1 million, the Wire Arc Additive Manufacturing system was sold through the Australian 3D printer manufacturers US Scale-Up strategy, which delivered over AUD$12 million in orders last year. This initiative seeks to address supply challenges within the US Department of Defense, particularly the US Navys submarine industrial base.US Navy SM-6 missile. Photo via the US Navy.Away from defense manufacturing, 6K Energy, a division of advanced material specialist 6K, signed a strategic supply agreement with metal recycling firm Aqua Metals. Through this partnership, the companies are working to build a circular supply chain for lithium-ion battery materials in the United States.The collaboration sees Aqua Metals supply 6K with recycled battery materials from its Sierra ARC facility in Reno. 6K then uses its UniMelt microwave plasma technology to convert these critical materials into cathode active materials at its PlusCAM factory in Jackson, Tennessee. Recycled battery materials are later sold to US-based manufacturers.This aligns with the US Governments efforts to re-shore its production capabilities amid global supply chain challenges. By 2030, the lithium-ion battery manufacturing capacity in the US is expected to reach nearly one terawatt-hour.6K Energy PlusCAM factory. Image via 6K Energy.Support-free metal 3D printingIn April, a key development in metal 3D printing came from Farsoon Technologies. The Chinese 3D printer manufacturer introduced its Support Reduction System to address common support-based challenges in metal powder bed fusion 3D printing.According to Farsoon, the technology combats stress and warping during the cooling process after 3D printing. This often causes parts to crack, especially in overhanging areas. The new technology facilitates reliable, support-free 3D printing of inverted conical structures with angles between 20 and 25, and round holes up to 50 mm wide.These capabilities reduce material requirements, translating to significant cost savings, cutting time commitments, and minimizing damage associated with support removal. The technology also facilitates the creation of more intricate part geometries, creating the potential for previously unachievable features.The fabrication of unsupported horizontal circular openings, reaching widths of up to 50 millimeters. Image via Farsoon.3D printing medical devices The increasing adoption of 3D printing for medical applications was also evident this month. Researchers from Nottingham Trent University produced realistic 3D printed heart and lung models that bleed, beat, and breathe like their real counterparts.Targeted to organ transplant training applications, the heart models reflect the tactile qualities of the real thing. They can be produced with different tissue hardness levels, allowing surgeons to plan operations.The 3D printed organs can also be used to research and teach transplant procedures. Most trainee surgeons currently practice with cadavers and animal organs, as existing models arent realistic enough. The researchers claim their 3D printed models are the first to offer the realism required for medical training.Elsewhere, biomedical 3D printing firm ArcomedLab announced that it had established the worlds largest case list of 3D printed craniomaxillofacial implants. By April 2024, the firm had completed 700 successful cases throughout Latin America, including in Chile, Peru, Colombia, and Mexico.The implants were 3D printed in a PEEK biopolymer material and personalized to meet specific patient needs. They can also store and deliver liquid drugs at the point of need through the companys patented gravity-induced drip mechanism. This allows drugs to be administered up to 20 days after surgery.Senior research fellow Richard Arm holding a 3D printed heart model. Photo via Nottingham Trent University.3D Printing News Highlights from 2024: Innovations, Trends, and AnalysisAll the news from Formnext 2024.Subscribe to the 3D Printing Industry newsletter to keep up with the latest 3D printing news.You can also follow us on Twitter, like our Facebook page, and subscribe to the 3D Printing Industry Youtube channel to access more exclusive content.Featured image shows a US Navy SM-6 missile. Photo via the US Navy.