Technologies

Powder Metal Technology

Powder Metallurgy is a "leading edge" manufacturing process utilised by Sumitomo to make high performance metal components from metal powders for a wide range of product applications.

The components are made by compacting metal powders in high precision dies and then heating the resultant "pre-formed" part to a temperature below its melting point, causing the compressed powder particles to bond together.

The Powder Metallurgy process as compared to conventional methods produces components of high precision and complicated shapes in large quantities.

  • Mixed Powder

    The metal powders and lubricant are mixed together so that the particles are evenly distributed. As the images show, powder particles are not round in nature.
  • Compacted Body

    The high pressures used in the compacting process cause the metal particles to stick very tightly together in the shape of the component die, forming what is known as a "Compact Body".
  • Sintered Body

    The components are then passed through a "Sintering Furnance" which causes the iron particles to bond together while atoms of the other powders in the components diffuse into the iron.

Powder Metal Production Techniques

Mixing

Compacting

Sintering

Iron and additional elements, such as copper, carbon or nickel, are mixed together in a dry state prior to compacting.

The mixed powder is fed into high precision dies and compressed to a pressure of 3-5 ton/cm², resulting in a component close to its final shape.

The compacted parts are then heated to between 1100-1150ºC in a sintering furnace, during which the metal particles are welded together to form components with the desired mechanical strength.

Finishing

Inspection

Finished Product

The sintered components can be given various finishing treatments depending upon requirements.

  • Sizing
  • Machining
  • Steam Treatment
  • Heat Treatment
  • Induction Hardening
  • Shot Blasing

Components undergo stringent quality control inspection at every stage of the manufacturing process with a final one at the end to confirm the specifications and quality.

The resultant components are packed and delivered as per Customers' requirements.

P/M Material Specifications for "CODE M&D" Series Chemical Compositions and Mechanical Properties

Classification Series Typical Chemical Composition (%) Density
(g/cm³)
As Sintered After Carburization and Hardening
Fe Cu C Other Hardness Tensile Strength
(kg-f/mm²)
Elongation (%) Inpact Strength (kg-m/cm²) Hardness Tensile Strength (kg-f/mm²) Bending Strength (kg-f/cm²)
Code M (Medium Density) M-15 bal. --- --- <1 6.2~6.6 HRF 30~60 10~20 3~10 0.4~1.0 --- --- ---
M-20 bal. 1.5 --- <1 60~90 15~25 2~4 0.4~0.7 --- --- ---
M-25 bal. 1.5 0.4 <1 HRB 10~75 20~30 1~3 0.3~0.6 HRA 60-76 30~40 45~60
Code D (High Density) D-20 bal. --- --- <1 6.7-7.0 H R B 15~50 15~25 2~6 0.8~1.5 --- --- ---
D-30 bal. 1.5 0.4 <1 30-80 25~35 2~4 0.8~1.5 H R A 60~80 40~60 90~130
D-40 bal. 2.0 0.7 <1 55-85 35~45 1~3 0.5~1.5 60~80 65~80 120~150