MIM-304

Overview of MIM and PCM Processes

The essential advantage of both MIM and PCM is that the molding process defines the complex final part geometry before sintering creates the solid metal piece. It enables intricate, high-precision metal components.

Understanding Stainless Steel MIM-304 Alloys

Stainless steel MIM-304 is a metal injection molding (MIM) grade powder of austenitic stainless steel that conforms to the AISI 304 alloy specification. Austenitic 304 stainless steels are one of the most common and versatile stainless steel alloys used across many industries. They contain, at minimum, 18% chromium and 8% nickel as the main alloying elements. 304 stainless exhibits excellent corrosion resistance, good formability, and weldability and has relatively high strength. It is also easily sterilized for medical uses.

MIM-304 powders are explicitly designed for metal injection molding processes. The powders have controlled particle size distributions and optimized morphology. Typical applications of MIM-304 parts include medical and surgical instruments, dental implants, watch components, nozzles, valves, and other small precision metal parts needing corrosion resistance. MIM enables complex 304 stainless steel part geometries to be mass-produced at a low cost compared to other manufacturing methods. Finished MIM-304 components have material properties similar to traditional wrought 304 stainless steel alloys in terms of corrosion resistance, strength, etc. MIM-304 is an essential material for injection molding small, intricate stainless steel components with the corrosion resistance and biocompatibility of 304 alloys. The MIM process imparts added benefits of design flexibility and cost-effectiveness at high volumes.

MIM-304 Chemical Composition

MIM-304 is an austenitic stainless steel grade containing 18-20% chromium, 8-10.5% nickel, and low carbon, manganese, silicon, phosphorus, sulfur, and nitrogen content. The balanced composition provides optimal corrosion resistance, strength, and manufacturability for metal injection molding powders. Key alloying elements like chromium and nickel enhance properties like oxidation resistance while minimizing elements like carbon reduces deleterious carbide precipitation. MIM-304 exhibits an austenitic FCC crystal structure with an excellent combination of properties for precision metal components.

MIM-304 Mechanical Properties

MIM-304 stainless steel exhibits high strength with 500-650 MPa tensile strength, 170-310 MPa yield strength, and 170-310 MPa fatigue strength. It maintains good ductility with 40-50% elongation and 45-65% reduction of area. Hardness ranges from 92-201 HV. MIM-304 provides excellent corrosion resistance in a variety of environments. Finer stainless steel powders below 10 microns can further enhance properties like fatigue life, elongation, and corrosion resistance. The combination of strength, ductility, and corrosion resistance make MIM-304 an ideal choice for small precision metal parts across many demanding applications.

Compare With Other MIM Stainless Steel

MIM-304 is the most widely used all-around stainless steel for metal injection molding. It provides a good balance of corrosion resistance, mechanical properties, weldability, and cost-effectiveness. 316L offers improved corrosion and pitting resistance versus 304 for harsh environments. Martensitic grades like 420, 440C, and 17-4 PH provide exceptionally high hardness and strength but with reduced corrosion resistance. MIM-430 is a lower-cost ferritic stainless option. For superior corrosion resistance in highly corrosive applications, 316 may be used over 304 but with increased cost. 304 is the most versatile and economical MIM stainless grade for small precision parts across various demanding applications.

Key Takeaways:

- 304 is the most commonly used standard stainless steel, offering good corrosion resistance and balanced mechanical properties.

- 316L improves corrosion resistance, especially against pitting and acids, but has slightly lower strength. Famous for medical uses.

- 17-4 PH has high strength, hardness, and moderate corrosion resistance. They are used where high strength is critical.

- 420 provides increased hardness and wear resistance versus 304.

- 440C is a high carbon martensitic grade optimized for very high hardness at the expense of corrosion resistance.

- 430 provides essential corrosion protection at a low cost but has lower strength.

Applications of MIM-304

The key advantages of MIM 304 in these applications are corrosion resistance, high strength-to-weight ratio, complex geometries, precision, and economical high-volume production. The MIM process enables small, intricate 304 stainless steel components to be manufactured cost-effectively. Here are some of the critical applications and industries utilizing stainless steel MIM-304 powders:

Medical - Surgical instruments, dental implants, orthopedic implants, medical devices requiring sterilization and biocompatibility.

Consumer Products - Watch cases, watch bands, eyewear components, jewelry.

Automotive - Small precision metal parts like valves, gears, and pump components.

Aerospace - Critical components, including turbine blades, fuel system parts, and fasteners.

Chemical Processing - Corrosion-resistant piping, valves, fittings, and pump parts.

Electrical - Sensors, connectors, power distribution components, insulation fasteners.

Marine - Corrosion-resistant hardware, propeller shafts, marine fittings.

Food/Beverage - Corrosion-resistant metal tubing, instrumentation, valves, and machine parts.

Oil and Gas - Wellhead components, downhole tools, valves, fasteners, and pump parts.