Breaking Through Robot Mass Production: Powder Metallurgy and MIM Overcome Dual Challenges of Weight and Cost

As humanoid robots gradually move out of laboratories toward large-scale mass production of 100,000-unit levels, and collaborative robots evolve toward “lightweight, efficient, and affordable” performance, the selection of manufacturing technologies has become a core variable determining the industry’s implementation speed and development scale. Faced with three prevalent industry bottlenecks—excessive weight, high costs, and hindered mass production—powder metallurgy and MIM (Metal Injection Molding) have emerged as key solutions to break through production constraints, thanks to their unique technical advantages, while redefining industry standards for precision manufacturing in robotics.

In the robotics sector, lightweight design and cost reduction are interdependent core objectives. Body weight directly impacts a robot’s battery life and motion flexibility. For humanoid robots in particular, every 10% reduction in body weight can increase endurance by more than 15%. Meanwhile, stringent cost control is an essential prerequisite for large-scale production at the 10,000- and 100,000-unit levels. Currently, the high unit cost of humanoid robots stems mainly from the low efficiency and severe material waste of traditional manufacturing processes for precision components, slowing the widespread adoption of the industry.

Traditional precision robotic components mostly rely on CNC machining and forging. These methods achieve material utilization rates below 50%, wasting large amounts of metal raw materials, while involving complicated processes and low production efficiency, which directly drive up component costs. Furthermore, the heavy structures produced by conventional processes hinder lightweight upgrades and run counter to the global trend of low-carbon and green manufacturing.

Powder metallurgy and MIM precisely match the core demands of robot mass production, making them the optimal solution that combines low-carbon emission reduction, cost efficiency, and lightweight performance. As a core near-net-shape technology, powder metallurgy produces components via metal powder compaction and high-temperature sintering, with a material utilization rate exceeding 95% and energy consumption reduced by approximately 60% compared with CNC. It saves raw materials at the source, enables low-carbon production, and aligns with the green transformation of global manufacturing.

As an advanced extension of powder metallurgy, MIM maximizes precision and efficiency by integrating metal powder and plastic injection molding. It can form thin-walled parts, irregular holes, and complex multi-structured components in a single step that are difficult to produce via traditional processes, with dimensional precision controlled within ±0.03 mm. This perfectly satisfies the high-precision requirements of core components such as joints and reducers. Additionally, integrated molding reduces assembly steps, further cutting costs.

Notably, both processes are compatible with lightweight high-performance materials such as titanium alloys and aluminum alloys, enabling component weight reduction of 20%–30%. In particular, strain wave gear flexsplines manufactured via MIM can achieve a weight reduction of 60%, with sintered density reaching 95%–99% of the theoretical value and mechanical properties close to forged parts. This balances lightweight design with high strength and wear resistance, suitable for the long-term, high-frequency reciprocating motion of robots.

The robotics industry has now reached a tipping point for mass production. Leading products such as Tesla Optimus and Xiaomi CyberOne have entered the 10,000-unit delivery phase, imposing higher requirements on component production capacity and cost control. With their core strengths of high material utilization, efficiency, and low cost, powder metallurgy and MIM have become preferred choices in the core supply chains of leading enterprises. As production scales up in the future, these technologies will thoroughly break through process bottlenecks and empower China’s intelligent manufacturing to seize a commanding position in the global robotics industry.