POWDER METALLURGY

 POWDER METALLURGY


Definition:- What does Powder Metallurgy (PM) mean?

Powder metallurgy (PM) is a process for forming metal parts by heating compacted metal powders to just below their melting points. In other words PM is metal shaping process that creates near-net parts from powdered metal.

Powder metallurgy is the process of blending fine powdered materials pressing them into desired shape or form (compacting), and then heating the compressed material in a controlled atmosphere to bond the material (sintering).


The powder metallurgy process consists of four basic steps.

  • Powder manufacture
  • Powder blending 
  • Compacting
  • Sintering

Advantages


The PM process provides a host of advantages over competing metalworking technologies moluding.
  • Cost effectiveness
  • Shape and material versatility
  • Application versatility
  • Part-to-part uniformity
  • Virtually unlimited choice of alloys and non metallics with associated properties
  • A variety of metal or non metal powders can be used.
  • Refractory materials are popularly processed by PM.
  • Can be very economical for mass production (100,000 parts).
  • Long term reliability through close control of dimensions and physical properties.
  • Very good material utilization-loss of material very less.
  • Minimization or elimination of Machining.
  • Very good surface finish can be easily obtained.

Limitations of Powder Metallurgy

  • Initial Investment cost high
  • Limited part size and complexity
  • High of powder material
  • High cost of tooling
  • Less stronger than wrought ones
  • Fracture toughness may be  low
  • Less well known process
  • Health hazard to the operator due to very fine powder being processed

Applications of Powder Metallurgy

Powder metallurgy parts are used in a variety of end products such as

  • Hardware 
  • Automobile parts
  • Washing machines
  • Powder tools
  • Copiers and postage meters
  • Hunting knives
  • Hydraulic assemblies
  • X-ray shielding
  • Oil and gas drilling well - head components
  • Only method for shaping super alloys and tungsten carbides
  • Automobile parts- A commercial US car contains approximately 15 kg of PM parts
  • Aerospace- A commercial aircraft engine is composed of 700-2000 kg PM parts.
  • Gears, Cams, Sprockets, Cutting tools, Piston rings, connecting rods and many house hold goods are produced by PM technique.

TO LEARN MORE ABOUT PM CLICK ON THE BELOW LINK

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