Precision Forming Solutions for Medical Implants: The Core Competence of Metal Injection Molding

The forming precision, material properties, and biocompatibility of medical implants are directly tied to patient health. Metal Injection Molding (MIM) technology, leveraging its unique advantages, has emerged as a core solution for the precision forming of such implants, redefining manufacturing standards. From dental implants to orthopedic internal fixation devices, the core competence of MIM technology runs through the entire manufacturing process of medical implants.

 The solid technical foundation of MIM stems from its process characteristics, which integrate the strengths of powder metallurgy and injection molding: metal powder is mixed with binders to form feedstock, which is then processed through injection molding, debinding, and sintering to produce high-precision components. This process breaks the bottlenecks of traditional manufacturing methods—mechanical machining involves cumbersome procedures and insufficient precision when dealing with complex structures, while casting struggles to control porosity. In contrast, MIM enables one-step forming of complex structures with little to no need for subsequent processing, making it particularly suitable for millimeter-scale micro-implants. Micron-level precision stands as MIM’s core competitive edge. The precision of medical implants directly impacts their fitting performance; for instance, a hole position deviation of over 0.1 millimeters in orthopedic bone plates may lead to postoperative risks. Through full-process control, MIM limits dimensional tolerance to a range of ±0.005 to ±0.02 millimeters, with a surface roughness Ra ≤ 0.8 microns. By regulating powder particle size and binder ratio during feedstock preparation, strictly controlling parameters in the injection molding phase, and implementing precise temperature control in sintering, multiple process links work in synergy to achieve high-precision adaptation. Material adaptability demonstrates the technological flexibility of MIM. The technology is compatible with a variety of medical-grade materials, including titanium alloys, medical stainless steel, and cobalt-chromium alloys. Titanium alloy implants produced via MIM achieve a density of over 98%, whose mechanical properties are comparable to those of forged parts. MIM also optimizes the composition uniformity of stainless steel and controls the grain size of cobalt-chromium alloys. Additionally, the biocompatibility and tissue integration capability of implants can be further enhanced by applying bioactive coatings or fabricating porous structures. MIM achieves a dual breakthrough in mass production and personalized customization. For mass production, mold-based forming enables automated continuous operation, boosting efficiency by 5–10 times compared with traditional machining and significantly reducing costs. In personalized customization, combined with medical imaging and rapid tooling technology, customized implants can be manufactured within a few days, perfectly adapting to the anatomical structures of different patients. Stringent compliance serves as a critical guarantee for its medical applications. MIM adheres to the ISO 13485 standard, implementing full-process traceability—from the inspection of high-purity raw materials, real-time monitoring of the production process, to precision testing and biocompatibility verification of finished products. At present, related products have obtained certifications such as FDA, CE, and NMPA, and are widely used in clinical practices worldwide. With its four core advantages in precision, material compatibility, efficiency, and compliance, MIM technology has become the preferred solution for the precision forming of medical implants. It continues to drive the industry toward minimally invasive and personalized development, providing more reliable medical support for patients.