METALLIC ALLOYS

Baroni Francesca ,Bertoni Cesare ,Bosi Niccolòc, Krumpf Martin,Leonardi Giacomo

iii^ES

what are alloys ?

COAL

+

IRON

----->

STELLORCAST IRON

* click animation to open phargraphs

Made to improve some Specific qualities of the starting metals,to obtain Materials with specific properties.

Metallic alloy is a material obtainedfrom amixture of multiple metals and othernon-metallic elements

How they are created ...

Heat up to the melting of individual alloy components ...

Dispersion of components as ina liquid solution...

cooling until solidification

TYPES OF ALLOYS

In aN ALLOY you may have different cases Based on the mutual actions OF atoms:

Disordered solid solutionORDERED SOLID SOLUTIONIntermetallic compoundeutectic alloying

* click animation to open phargraphs

If different atoms attract a lot less than the same atoms and thus alternate the crystals of one and the other composition, as there is no solubility in the solid state

Different atoms with very different electronegativities, in the case where a component is so electronegative to produce an ionic compound it has a chemical compound

If different metal atoms attract with different forces

Different atoms that are attracted by forces similar to those between the same atoms, resulting in homogeneous and random atomic distribution

bronze

it was the first discovered and used alloy in prehistoric times (Bronze Age).For a long time unused, due to the considerable costs of its productionGood electrical conductivity, due to the large amount of copperHigh friction and heat resistance (electric motors, special bearings and springs)

used in the past for creation of swords and statues, but now ...

uses of titanium in aereonautic fieldALPHA AND BETA PHASES

STEEL

The alloy is mainly composed of iron and carbon, not more than 2.06%: beyond this limit, the properties of the material change and are referred to as cast iron. They can countless alloying

TITANIUM

It has positive redox potential, so if coupled with another material it tends to shrink, the titanium is particularly suitable for coupling with composite materials.The alligators are distinct from: α - stabilizers; they Enter the solution preferably in phase α and increase the stability temperature (Aluminum, oxygen, nitrogen, zirconium, pond). β - stabilizers; Enter solution preferably in step b and lower the stability temperature. Vanadium, chromium, molybdenum, tungsten, tantalum, niobium.

STELL IS AN ALLOY USED IN MANY FIELD

biomedical applicationtitanium's biocompatibily

* click animation to open phargraphs

Alloys with a percentage of between 9 and 12% of tin are the most widely used ones with regard to gear construction. Conversely, alloys with a percentage of 12 to 22% of tin are formed by a rather hard constituent and dispersed in a tenacious metallic matrix, a feature that makes bearing alloys particularly suitable. In addition, there are also percentages that reach up to 30% of the tin and in these cases the bronzes are hard and susceptible, which can emit ringing sounds if beaten, which makes it possible to improve the fusion of the bells.

Certain titanium alloys with small percentages of Aluminum, Iron, Molybdenum and Vanadium, which can replace austenitic stainless steels used for critical turbine parts, the behavior of these high temperature alloys was also higher than that of the best ferrous alloys.

The phase α has a great resistance to creep. The hexagonal structure has limited deformation capabilities, increasing resistance to it and providing ductility.It is characterized by good weldability.The β phase reduces the resistance to deformation at high temperatures All the mechanical properties of an alloy containing β depend heavily on thermal treatment

The exceptional biocompatibility of this material has been recognized by medical research. Titanium has an extremely low toxicity and is well tolerated by both bone and soft tissues. Histopathological examinations did not detect mutated cells near the titanium implants. There is a tightness of the soft tissue adjacent to the CP titanium implant, which may be due to the low hardness and poor abrasion resistance of unbound material. Titanium is readily formed of titanium oxide or complex oxides and hydrides, so it is possible that some of the material removed from the implant is immediately stabilized by the formation of these inert materials and the tissues do not seem to respond to chemically inert titanium oxides. Titanium oxide is used in dermatological treatment creams. The material has therefore proven safe in intravascular applications due to high electronegativity and passive surface.

Significant progress has been made in the development of medical instruments and implants that also last over twenty years. The required materials have to be increasingly sophisticated and titanium and its alloys have been tested in numerous situations.Many titanium alloys have been found to be suitable for medical applications, in fact they play a key role in numerous surgical applications in the orthopedic, cardiovascular and dental fields.