Technical seminar on

By Mohammad Azhar Hussain

14311A04H6

Printing

Printing :

Printing is a process for reproducing text and images, typically with using ink or paper using print press

3D Printing:

It is also called as ‘Additive Manufacturing’

It is a method of Additive Manufacturing that adds material to an object layer by layer to create the final product.

It was developed in 1984

3D Printer

3D printer connected to a PC prints a solid object

Additive Manufacturing:

Working :

A 3D file is checked by software to see if it is printable.

The software then slices the file and sends it to a machine.

A plastic filament is fed through the printing head. The filament melted and the head then deposits it

on a build platform. The head moves around depositing the material so

that it makes up the bottom slice of the object. The head returns to its starting position and the

build platform is lowered. The head then builds the new layer on top of the

first and this is repeated until the object is done.

Continuation…..

When the model is finished,it is suspended in the powder to cure

At the end of the curing time,the machine automatically removes the most of the powder around the model by vacuum pressure

Methods :

There are three main methods of 3D Printing.

1) Selective Laser Sintering (SLS)

2).Stereolithography (SlA)

3).Fused Deposition Modelling (FDM)

SLS :

Selective Laser Sintering (SLS) is an additive manufacturing (AM) technique that uses a LASER as the power source to sinter powdered material (typically metal), aiming the laser automatically at points in space defined by a 3D model , binding the material together to create a solid structure.

LASER used in SLS is CO2 laser

SELECTIVE LASER

SINTERING :

SLA :

Stereolithography is an additive manufacturing process which employs a vat of liquid ultraviolet curable photopolymer "resin" and an ultraviolet laserto build parts' layers one at a time. For each layer, the laser beam traces a cross-section of the part pattern on the surface of the liquid resin. Exposure to the ultraviolet laser light cures and solidifies the pattern traced on the resin and joins it to the layer below.

SLA :

FDM :

A plastic filament or metal wire is unwound from a coil and supplies material to an extrusion nozzle which can turn the flow on and off. There is typically a worm-drive that pushes the filament into the nozzle at a controlled rate

FDM:

Various polymers used

ABS

Poly carbonate(PC)

Poly acetic acid(PLA)

High density polyethylene(HDPE)

Polyphenylsulfone(PPSU)

ABSplus:

ABSplus is a production grade thermoplastic That gives models the ability to perform just like production parts in real world.

This is commonly used polymer in three dimensional printers.

ABS plus

Advantages:

3D printing uses non-harmful chemicals

3D printing generates almost no waste during the process.

It can be used for making replacement parts.

Applications:

Few Printed Objects :

Limitaions :

The machines are too expensive and not reliable. 

Materials are not strong enough.

It is too hard to design for 3D printing. 

Machines are not fast enough.  

Any questions ?