Powder Metallurgy Guide: Pressing, Sintering, and Design for Chinese PM Parts

What is Powder Metallurgy?

Powder metallurgy (PM) is a metal forming process where metal powders are compacted into a die and then heated (sintered) below the melting point to bond the particles. It produces near-net-shape parts with minimal waste.

Advantages: 95%+ material utilization, no secondary machining needed for most applications, good for complex geometries in medium-to-high volumes (10,000+ parts).

PM Process Steps

Step 1: Powder blending — mix base metal powder with lubricants and alloying elements

Step 2: Compaction — press the powder in a die at 400-800 MPa

Step 3: Sintering — heat to 1120-1300°C in a controlled atmosphere furnace

Step 4: Sizing (optional) — re-press for tighter tolerances

Step 5: Infiltration (optional) — impregnate with copper or polymer for sealing

Step 6: Post-processing — steam treatment, plating, or heat treatment

Common PM Materials in China

Material | Density | Tensile Strength | Typical Applications

--- | --- | --- | ---

FC-0205 (Fe-2Cu-0.5C) | 6.6 g/cc | 280 MPa | Structural parts, gears

FC-0208 (Fe-2Cu-0.8C) | 6.6 g/cc | 350 MPa | Higher strength gears

FN-0205 (Fe-2Ni-0.5C) | 6.8 g/cc | 320 MPa | Automotive components

SS-316L (Stainless) | 6.4 g/cc | 250 MPa | Corrosion-resistant parts

Brass (Cu-10Zn) | 7.5 g/cc | 200 MPa | Decorative, low-load

Chinese PM Industry

China is the world's largest PM parts producer, with annual output exceeding 800,000 tons. Main clusters: Ningbo (Zhejiang), Laiwu (Shandong), and Chongqing. Typical lead time: 3-6 weeks for tooling, 2-3 weeks for production. Minimum order quantities typically 5,000-10,000 parts for economical pricing.