ALLOY, ADHESIVE... Flashcards
is a new technique in which moulds are made using compressed metal powders, even though this method is more expensive (As it involves preparation of metal powder).
POWDER METALLURGY
This method has many advantages over the traditional method. Metals and alloy can be made into metal powders. The metal powder is then used for making the articles.
POWDER METALLURGY
Powder metallurgy is an art of making metal articles of desired shape using metal powder by __________ AND _____________
HEAT TREATMENT AND COMPESSION
Articles can be made by using
3
1.Single metal powder
2.Mixture of metal powders
3.Mixture of metal and non-metal powders
Metal powders with particle size ranging from _______Microns are produced. Usually metal powders with particle size ______microns are predominant.
1 TO 100
10 TO 20
The powder metallurgical process consist of the the following two steps.
1.Powder production
Powder fabrication
2 STEPS Preparation of metal powder
ATOMIZATION
REDUCTION OF METAL OXIDE
is suitable for metals with low melting point like zinc, lead, tin, aluminium etc.
ATOMISATION METHOD
is suitable for the metals with high melting point like tungsten, iron, copper, nickel etc.
REDUCTION OF METAL OXIDE
The melting point of Lead is _________.The melting point of tin is ____c.
327
231
IS an alloy of tin and lead
SOLDER
Alloys are _________ MIXTURE of two or more metals.
homogeneous mixture
are prepared by fusing together the different ingredients (metals) in a furnace.
ALLOY
Purpose of alloying
1.To increase the hardness of the metal.
2.To increase the tensile strength of the metal.
3.To make it corrosion resistant.
4.To enhance the malleability and ductility.
5.To get attractive surface and appearance.
6.To make it abrasion resistant.
7.The machinability of the metal can be improved.
8.Melting point of the metal can be decreased.
9.The colour and metallic luster can be improved.
2 Types of alloys
1.Ferrous alloys
2.Non-ferrous alloys