Machining is the expensive materials and not all materials can be easily machined and not the finished article mechanical properties and machining weakens the fibrous structure. For example, drawing a metal blank: It is a technique to cut and tear the metal into desired shapes. It is expensive and wasting tree method of manufacturing. On the other hand cooling solutions are not uniform and good fluidity and do not provide enough tensile strength and toughness. Forging is forming but the metal into shapes specified by applying external force large hot ingot. Operation is fast but the cost to run the relatively high pressing machine. Create offers perfect tensile strength and toughness to the material at high speed with great pressure. It is one of the most popular manufacturing techniques. Creation makes changing tools. Creation is done after warming up the material because it is easier to work with hot metal. High temperatures cause the material to crumble and lose its malleability. However forgery
1) Chorus grain structure.
2) draws out the undesirable substances (nonmetallic).
3) Remove the internal cavities.
4) The mechanical properties but not increase hardness.
5) improved fibrous structure.
6) Remove oxide layer on the hot topic.
Metal grain structure is the same as wood and it is easier to split it along back. Shall the strength of the fibrous structure. Types of creation:
1) create Open dice: no death, but the crushed material to be made thinner and stronger. Eg Ships will propeller. Create can also use Open die for raw material preparation. Forging Process in order to reach the desired grain flow usually does die blocks.
2) create warm wishes: right-create temperature reached gradually. By the heat treatment to reduce internal stresses and relax metal. After removing the ingot from the furnace is immediately forged giving strength max. Fibrous structure has improved in all three dimensions. Excess metal is called flash from the finished article after creation.
3) Forging upset: Some part of the metal (billet) goes about creating. By the technique increased diameter without reducing its strength. This should be done by creating a proper temperature to prevent cracks. A one bolt, one can round by a punch or hardware item similar to the operation done. After creating machining applied to the metal.
4) Roll Forging: material passing through rolling dice, which is non-uniform surface with different depths, and gives the pad facing the metal to shape the surface of the metal.
5) Drop Forging Hammer: Huge cyclical force has dropped a uniform material and remove the crankshaft diesel produced technique. In this technique 20% of waste material called flash. Each operation between the two halves of the dice fine graphite sprayed with oil to prevent the metal from sticking to the die and to prevent throwing the dice and cool the die.
After creating a work that is the oil quenched and tempered to increase its hardness. Some principles and limits in die design to include
1) the separation line: it divides the upper die from the lower die. Impact of grain in its design flow, flash formation.
2) Draft: Size taper the side of the part required to use the death. Draft angles of precision forgings near zero.
3) Webs and ribs: a very thin web of creating parallel to the line while its thin rib perpendicular to the parting line. These features cause metal flow problem as they are thinner.