i want to know the reasons that pure aluminium and copper are classified as easy to machine materials?

Answer 1

*The easiest of the coppers to machine are the special free machining grades which approach the ease of machining of the standard brass. The machining properties of all the materials vary and it is suggested that for best results the tool angles, cutting speeds and lubricants should be selected from those recommended in the CDA publication TN44 "Machining Brass, Copper and Its Alloys" .
*Al and Cu are ductile materials and lighter too compared to steel and other alloys of steel. The only thing is to selection of cutting tool, feed,speed and setting of cutting angle.
We should be quality conscious.Galling action during machining is inevaitable in machining the softer metals.

Please visit:
http://www.espi-metals.com/tech/machiningaluminum.pdf

[Sulphur and tellurium are added to copper to give free machining properties.]

Answer 2

Machinability rating (hard to machine, easy to machine) is given to a material based on how it compares to ferritic ductile cast iron. The rating varies depending on who published the list and what criteria they most heavily weighted when defining their scale. It combines several factors - Hardness, abrasiveness, brittleness, and others. Generally, anything over 1.0 is considered easy to machine, or free machining. Anything under 1.0 becomes progressively more difficult to machine.

As a general note, not all copper alloys are are free machining. Some are actually quite difficult to machine.

Other factors must be taken into consideration when considering machinability of a material from a practical rather than academic standpoint. A harder material may be more preferable to a more wearing material if you have a high horsepower machine; you can remove more material without wearing down the tool in a hard material, where several changes of tooling might be required in a more abrasive, but softer metal (i.e. copper). Additionally, coefficient of expansion and other factors will cause difficulty machining high tolerances on certain alloys of certain materials.

For example, aluminum. Aluminum has a high amount of thermal expansion, and the most popular alloy, 6061, has the habit of cutting to an uncertain depth when working in higher tolerance ranges due to gumminess. If the object is accuracy, 6061 may be a far more difficult substance to machine than tool steel.

Answer 3

Classified "easy" by whom? Pure copper and aluminum are actually fairly difficult to machine. While it is true the material being cut has to be softer than the tool used to do the cutting, if the metal is too soft it can tend be gummy, stick to the cutting tool, tear and/or create stringy chips that are hard to handle.

Answer 4

I would not classify copper as easy to machine, but it is easier than many other substances. A substance is easy to machine if it is ductile enough to form a long chip when attacked by a cutting edge, as in a lathe. Both aluminum and copper qualify, although copper has a tendency to get dug into by an edge.

Answer 5

The tools used to work a metal should be harder than the metal being worked. Otherwise your tool will wear down at nearly the same rate or faster depending on the metal of the tool.

For example, you could use a copper saw blade to cut many pieces of aluminum but it would take many aluminum saw blades to cut a single piece of copper.

Answer 6

If by skill of magnetic you advise ferro-magnetic (you may magnetize it, and it will stay magnetized, and so forth), then no. All components have some magnetic properties even however, i believe that those components are what's widely used as diamagnetism, meaning that they are going to actual repel a magnet! (usually in maximum components the end result is quite vulnerable even however, different than in superconductors or below VERY reliable magnetic fields). in spite of the actuality that i think of aluminium is actual paramagnetic (behaves like a ferromagnetic cloth, yet lots lots weaker), yet I cant bear in mind. yet those components arent magnetic interior the conventional experience of the be conscious, like metallic or iron are.

Answer 7

They are both light,
depending on the color,
if you like light colors, you may want to use Al
if you like yellowish colors, you may want to use Cu
they both have properties that causes them to easily shape, bend, and are very light (if you want to build something that needs to go fast or be light)
takes less time to machine things with it, and it has real good material value, cheaper. you may like to also find out more by going to google and searching on material science. It will have it all in detail.
good luck

Answer 8

they are soft