Metals, Ceramics, UHMWPE, introduction TKR

Send This

Download

Comment

Favourite

more

Rating :

Rate It:

Embed :

Post a comment

Post Comment on Twitter Post Comment on SlideWorld

Comments:

Subscribe to follow-up comments

Notes

Hide Notes

Slide 1 :

Slide 2 :

Dr Wazir Ahmed PGR Orthopedics PIMS Islamabad

Slide 3 :

Types of materials Metals Polyethylene (PE) UHMWPE Ceramics Metal: Rough & Polished Ceramic Polymer

Slide 4 :

Matels Definition: An element is consider metallic if a positive charge is demonstrated on an electrolysis test. This test consists of dissolving the element in an acid & running a current through the solution. When such elements are fully reduced they are called metals.

Slide 5 :

Properties Elongation: Amount of deformation that a tensile stress or load will produce Modulus of Elasticity: A measure of rigidity or stiffness of a material Elastic Limit: the maximal stress a material can sustain without undergoing permanent deformation Yield strength: the stress at which elastic deformation ends & plastic deformation begins

Slide 6 :

Slide 7 :

Ductility: A metals ability to withstand plastic deformation without breaking Toughness: The ability of a material to absorb energy by deforming without breaking Ultimate tensile Strength: The maximal stress that a material can withstand in a single application without breaking Fatigue Fracture: A fracture or break of a metal caused by repetative applications of loads below the yield strength

Slide 8 :

Fatigue Strength: The maximal cyclic load that a metal can withstand without fracturing when subjected to a designated no of cycles typically 5 or 10 million

Slide 9 :

Groups of Metals There are three groups of metals Iron Based Alloys Cobalt Based Alloys Titanium Based Alloys

Slide 10 :

Stainless Steel These are iron based alloys Composition: Iron Chromium Nickel Carbon

Slide 11 :

Cobalt based Alloys Composition Cobalt Chromium Molybdenum Prosthesis Austin Moore Thomson Implants PCA AML

Slide 12 :

Titanium Based Alloy In 1951 Levanthal Introduced this Composition Titanium Aluminum Vanadium Implants Fracture plates Intramedullary Rods Femoral & Accetabular Implants

Slide 13 :

http://www.engr.sjsu.edu/WofMatE/projects/srproject/srproj3.html#overview

Slide 14 :

Ultra High Molecular Weight Polyethylene(UHMWPE) Definition: Polyethylene plastics are formed by polymerization of Ethylene. UHMWPE is a polyethylene with essentially the longest, least branched molecules possible to manufacture routinely High density Molecular weight 2-6 million

Slide 15 :

Removal or transfer of material from articulating surfaces due to their relative movement under load. British Standards Institution 1979 Wear :

Slide 16 :

Continuous deformation of a material when subjected to stress over an extended period. Change of dimensions without loss of material Creep :

Slide 17 :

Properties: Tough Extremely Chemically Inert Good Resistance to Creep Biocompatibility Causes of Failure Oxidative Degradation Catastrophic Rupture & Failure Of Implant

Slide 18 :

Ceramics Materials resulting from ionic bonding of A metallic ion and A nonmetallic ion (usually oxygen) Benefits Very hard Strong good wear characteristics 3 to 16 times less than metal Inert High compressive strength Ease of fabrication

Slide 19 :

Cont Examples Silicates , Metal Oxides – Al2O3 MgO Carbides – Diamond Graphite pyrolized carbons Ionic salts – NaCl CsCl ZnS

Slide 20 :

Ceramics (cont’d) Uses Surface Replacement Joint Replacement Problems Very brittle & Low tensile strength Undergo static fatigue Very biocompatible Difficult to process High melting point Expensive

Slide 21 :

THANKYOU

Dental Caries intro...

Introduction to Psor...

Introduction to Psyc...

Some precautions in ...

A new ceramic in tot...

Introduction to Heal...

Free Powerpoint Templates

	wazir130 1 Years ago.



809 Views, 0 favourite
PowerPoint Presentation on Metals, Ceramics, UHMWPE, introduction TKR
More By User Flag as inappropriate Select your reason for flagging this presentation as inappropriate. If needed, use the feedback form to let us know more details. Cancel