Introduction toModern Engineering Materials

By:R.PraBhaKaraN,

Ist yr. ECE,Sona College Of Technology

TOPICS TO SEE:∞ Ceramics∞ Composites∞ Refractory∞ OLED∞ Thin film∞ Bio-material∞ Nano-material

CERAMICSInorganic

and Non-metallic solid

It starts in 1403with manufacture of vaseFrom Porcelain(heated down clay)

Quartz,topaz,tourmaline,etc..,

Pyro electricity:

• Temperature sensors • Fire alarms • Motion sensing

APPLICATIONS:

Silicon nitride rocket thruster. Left: Mounted in test stand. Right: Being tested with H2/O2 propellants

Silicon carbide is used for inner plates of ballistic vests

Zirconium dioxide is used in manufacture of ceramic knife

OTHER APPLICATIONS

COMPOSITES

Good example isCompound semi-conductors

Material which is a combinationOf two or more materials of Different or same type to form aStronger material than them

Concrete

Concrete is a mixture of cement and aggregate,strong material that is very widely used

Plywood is used widely in construction

Plywood

Vehicle armourCombination of Metals, plasticsAnd some ceramicMaterials like SiCUsed in race cars and military vehicles

REFRACTORY

Material which retains itstrength even at higher temperaturesor else extremely heat resistant

Tantalum Hafnium Carbidehas highest melting point of 4215˚C

Tungsten(3422˚C) filamentof a bulb

Niobium alloyed with10%hafinium & 1%Tiused in nozzle for rockets

OLEDA layer of organicsemiconducting materialwhich emits light on electric interaction with the help of two electrodes

[

Schematic of a bilayer OLED: 1. Cathode (−), 2. Emissive Layer, 3. Emission of radiation, 4. Conductive Layer, 5. Anode (+)

Working

ADVANTAGES:

• Light weight• Flexible • Response time

DIS-ADVANTAGES:• Cost• Life span(5yrs only)• Power consumption (40% more than LCDs)• Water can damage OLED screen

THIN FILMLayer of materials rangingfrom nanometers to micrometerthickness

Common example issilvering of face glasses in home

Electrolyte is Lithium phosphorous oxynitrideLiPON

THIN FILM LI-ION BATTERY

Used in micro-electronicsWireless sensors

DICHROIC FILTER

WORKING

The thickness of the filmis equal to the light tobe reflected(color to be filtered)

BIO-MATERIALDevice or material implantedin specimens(humans) to cureor enhance the working ofparticular part

Cardiac pacemakerpowered by thin filmLi-ion battery

PACE MAKERS

REPLACEMENT MATERIALS

Hip replacement joints made from acetabular(ceramic material) and with titanium metal and cobalt chromium chemical to enhance bone growth

Bone replacement made from pure titanium metal plate

NANO-MATERIALThe materials with size less than100nm and have unique characteristicsAnd behavior

The study of nanoparticles had intenseresearch in the 1970’s-80’s in USA andJapan which they called Ultra-fine particles(UFP)

Size matters!The behavior of particlesvaries with size, for example goldin Nano scale appears red, thus Nanoparticles are very sensitive to light

APPLICATIONS

Wires of thickness 10−9 mEg:Ni,Pt,Au,etc..,

Nano-wires:

SEM image of 15nm NiIt’s conductivity decreasesWith decrease in size of diameterHence, used as a control unitin digital gates

Cancer treatment:

Nano-Cadmium selenide which glows in UV-region is injected into patientsbody, localize the cancer cells and visible more clear than other bio-dye

NANO-ROBOTS

They are estimated to locate and curetumors and cancers, but still in researchcondition due to its compatible issues

CARBON NANO-TUBEAllotropes of carbon with Cylindrical Nano structures

CNT’s applications

• Textiles• Power productions• Electronics• Medicines

PAPER BATTERY• Cathode: Carbon Nanotube (CNT)• Anode: Lithium metal (Li+)• Electrolyte: All electrolytes (incl. bio electrolytes like blood, sweat, moisture)• Separator: Paper (Cellulose)

WORKING ILLUSTRATION

DIS-ADVANTAGES:

ADVANTAGES:• Flexible• Easily rechargeable• Bio-degradable

• CNT’s are expensive• Brittle• Inhaled cause lung problems

Worker at carbon black plant in Sunray, Texas

MAIN DRAWBACK OF CARBON:Pure carbon is less toxic but continuous intake causes several biological disorder especially lung diseases

THANKS TO…• Wikipedia and G images• Supporting friends• Patient students