The core trade-off: AM's flexibility vs. its slow speed and high cost
Additive manufacturing builds objects layer by layer from a digital design, which gives it enormous design freedom and the ability to make complex, customized parts without expensive molds. But this same layer-by-layer process is fundamentally slower than traditional mass-production methods like injection molding, which can churn out thousands of identical parts per hour. A 2021 study found that AM's production rate is 'several orders of magnitude slower' than traditional plastic mass production technologies [3]. That speed gap is the central barrier to using AM for high volumes.
The cost picture is also challenging. A 2023 review of comparative studies found that AM only has lower production costs than traditional manufacturing when production volumes are below 42,000–87,000 units per year, depending on the AM process and part geometry [1]. Above that threshold, the per-unit cost of AM is simply too high. The same study found that AM's environmental impacts—including energy use and material waste—are lower than traditional methods only when production volumes are below about 1,000 units per year [1]. So for truly high-volume mass production (hundreds of thousands or millions of units), AM is currently neither cheaper nor greener.
Where AM can win in high volume: small parts, high waste, and smart operations
Despite the general limitations, there are specific conditions where AM can compete in high-volume production. The 2023 review found that AM becomes cost-competitive for parts that are small and would generate a lot of material waste if made by traditional methods [1]. For example, if a part requires machining away 80% of a metal block, AM's near-net-shape approach can save significant material and cost, even at higher volumes.
A striking real-world example comes from a 2021 case study of an AM shop that won a contract to supply 7.7 million products [5]. The company achieved this by combining technological innovations—improving AM process parameters for time, cost, and dependability—with operations management practices typically used in conventional factories, such as designing for volume, using low-cost resources, and optimizing material flow [5]. This shows that AM can achieve economies of scale, but it requires a system-wide approach, not just a better 3D printer.
Another promising strategy is hybrid manufacturing, where AM is combined with traditional methods. A 2021 study demonstrated a process that 3D-prints a baseplate and then overmolds a rib structure using injection molding [3]. This allows customization (via the 3D-printed part) while keeping the speed of injection molding for the bulk of the part. The researchers found that bonding strength between the two parts could be improved by creating porous structures in the 3D-printed part, into which the injection-molded plastic flowed [3].
The fundamental challenges that won't be solved by scale alone
The 2023 review makes a crucial point: the main barriers to AM for mass production are not primarily caused by economies of scale, so they won't be solved simply by the AM sector growing larger [1]. Instead, they require fundamental advances in three areas: material science (to reduce the cost and energy intensity of producing AM feedstocks), AM production technologies (to raise speeds and eliminate the need for support structures), and computer-aided design software [1].
A 2022 perspective article on additives in 3D printing echoes this, noting that as AM moves toward true manufacturing, it faces challenges in speed, mechanical performance, durability, and environmental interaction [2]. The article argues that additives—such as reinforcements, thermal stabilizers, and flame retardants—will play a critical role in meeting the stringent requirements of industries like aerospace, defense, and automotive [2]. So the materials themselves need to evolve.
On the positive side, a 2025 review of AM for biomedical bone implants highlights that AM is already revolutionizing that field by enabling customized, high-performance implants tailored to individual patients [4]. But even there, the authors note substantial cost implications and the need for new materials and process optimization [4]. This reinforces the idea that AM's sweet spot today is in low-to-medium volume, high-value, customized applications—not yet in high-volume commodity production.
Sources used in this answer
Is Additive Manufacturing an Environmentally and Economically Preferred Alternative for Mass Production?
Finds AM has lower environmental impacts only below ~1,000 units/year and lower costs only below 42,000–87,000 units/year; fundamental advances in materials, speed, and software are needed for broader mass production.
Current status and future roles of additives in <scp>3D</scp> printing—A perspective
Identifies speed, mechanical performance, durability, and environmental interaction as key challenges for AM in manufacturing, and argues additives will be critical to meet industry requirements.
Personalized Mass Production by Hybridization of Additive Manufacturing and Injection Molding
Proposes hybridizing AM with injection molding for personalized mass production; shows bonding strength can be improved by creating porous structures in the 3D-printed part.
Additive manufacturing for biomedical bone implants: Shaping the future of bones
Reviews AM for biomedical bone implants, highlighting its ability to create customized, high-performance implants but noting substantial cost and material development challenges.
Breaking the mould: achieving high-volume production output with additive manufacturing
Presents a case study where an AM shop won a contract for 7.7 million products by combining technological innovation with operations management practices, achieving economies of scale.