Author: haroonkhan
-
Production Machines, Tools, Fixtures, and Other Related Hardware
In manufacturing systems, the term workstation refers to a location in the factory where some well-defined operation is accomplished by man and/or machines. The machines used in manufacturing or assembly can be classified as follows: Manually Operated Machines: In manually operated machines, the machines only provide the power for operations but the control of operations is…
-
INTRODUCTION
A manufacturing system consists of all the resources required to transform the material from its raw form to finished form. The resources involved in this transformation process may be man, materials, money, machine, management, energy, etc. A manufacturing system’s components may be broadly categorized as follows:
-
APPLICATIONS OF POWDER METALLURGY
Powder metallurgy techniques are applied in manufacturing of a different kind of products. Some of them are mentioned as follows:
-
FINISHING OPERATIONS
These are secondary operations intended to provide dimensional tolerances and better surface finish. They are sizing, coining, machining, impregnation, infiltration, heat treatment, and plating. Sizing: It is repressing the sintered component in the die to achieve the required size with accuracy. Coining: It is repressing the sintered components in the die to increase density and to give…
-
SINTERING
Sintering involves heating of the green compact at high temperatures in a controlled atmosphere to protect from oxidation of metal powders. Sintering increases the bond strength between the particles. Sintering temperature is usually 0.6–0.8 times the melting point of the powder. In case of mixed powders of different melting temperatures, the sintering temperature will usually…
-
COMPACTING
The main purpose of compacting is converting loose powder into a green compact of accurate shape and size. The techniques adopted for compacting are pressing, centrifugal compacting, extrusion, gravity sintering, and rolling. Pressing: The metal powders are placed in a die cavity and compressed to form a component shaped to the contour of the die (Figure…
-
BLENDING/MIXING OF POWDERS
Blending and mixing of the powders are essential for uniformity of the product. Lubricants (such as graphite) are added to the blending of powders before mixing. The function of lubricant is to minimize the wear and to reduce friction. Different powders in correct proportions are thoroughly mixed either wet or in a ball mill to…
-
Methods of Production
There are various methods available for the production of powders. Some of the important processes are as follows: atomization, machining, crushing and milling, reduction, electrolytic deposition, shotting, and condensation. Atomization: In this method, molten metal is forced through a small orifice and is broken into small particles by a powerful jet of compressed air, inert gas,…