2. Course Contents
Commercial methods for the production of metal powders, powder
characterization and testing, powder conditioning and function of
addition agents.
Consolidation of metal powders, i.e. Pressing, Cold Isostatic
Compacting, Hot Isostatic Compacting, Powder Rolling, Powder
Forging, Powder Extrusion, Powder Injection Molding, and Spray
Forming.
Theory of Sintering, Sintering Practice, Sintering Atmospheres,
Sintering Furnaces.
Powder Metallurgy of Refractory and Reactive Metals, Powder
Metallurgy of Supper Alloys, Dispersion-Strengthened Materials.
Secondary operation performed on P/M parts and products.
Inspection and Quality Control for P/M Materials.
The economics of P/M Production.
3. Definition of Powder Metallurgy
Powder metallurgy may defined as, “the
art and science of producing metal
powders and utilizing them to make
serviceable objects.”
OR
It may also be defined as “material
processing technique used to consolidate
particulate matter i.e. powders both
metal and/or non-metals.”
4. Importance of P/M:
The methods of powder metallurgy have
permitted the attainment of compositions and
properties not possible by the conventional
methods of melting and casting.
Powder metallurgy is an alternative,
economically viable mass production method
for structural components to very close
tolerance.
Powder metallurgy techniques produce some
parts which can’t be made by any other
method.
5. The process of P/M is the process of producing
metallic parts from metallic powders of a
single metal, of several metals or of a
combination of metals and non-metals by
applying pressure. The powders are mixed
mechanically, compacted into a particular
shape and then heated at elevated temperature
below the melting point of the main
constituent.
6. Process of Powder Metallurgy:
The process of P/M in general consists of a series of
steps/stages to form a final shape. These stages are shown by a
simple flow sheet diagram.
Powder Production
Powder Characterization & testing
Mixing - Blending
Processing - Compacting
Sintering Operation
Finishing Operations
Finished P/M Parts
7. * Powder Metallurgy (P/M) is an improved alternative
method as compared to Industrial Metallurgy (I/M) being
more economical for large production series with
precision of design and savings of energy, material and
labor. Further it is a unique method for producing cermets,
cutting tools, nuclear fuel elements, self- lubricating,
copper-graphite brushes etc.
16. Advantages of P/M for Structural Components:
These may be classified into two main headings;
(a) Cost advantages, and
(b) Advantages due to particular properties of sintered components.
Cost Advantages:
(i) Zero or minimal scrap;
(ii) Avoiding high machining cost in mass production as irregularly
shaped holes, flats, splines, counter bores, involute gear teeth,
key-ways can be molded into the components;
(iii) Extremely good surface finish at very low additional cost after
sizing and coining;
(iv) very close tolerance without a machining operation;
(v) Assembly of two or more parts (by I/M) can be made in one
piece;
(vi) Separate parts can be combined before sintering.
17. Refrences
Fundamentals of powder metallurgy by
W. D. Jones
Powder Metallurgy: Principles and
Applications by F. V. Lenel
Fundamentals of P/M by I. H. Khan
