Intro to Mech Prototypes

Prototype

The first full-scale model of a product

Additive manufacturing

-formally called rapid prototyping

-parts are built in layers

-Physical models of parts produced by CAD data files

-Minutes to hours

-Uses a wide variety of materials

Stereolithography (SLA)

-curing liquid resin with UV light to create highly detailed and intricate parts.

-For concept models and cosmetic prototypes, SLA has proven to be far superior to other additive processes.

Categories of Additive Manufacturing

-VAT Photopolymerisation

-Material Jetting

-Binder Jetting

-Material Extrusion

-Power Bed Fusion

-Sheet Lamination

-Directed Energy Deposition

VAT Photopolymerisation

-uses a vat of liquid photopolymer resin, out of which the model is constructed layer by layer.

Material Jetting

-creates objects in a similar method to a two dimensional ink jet printer.

-Material is jetted onto a build platform using either a continuous or Drop on Demand (DOD) approach

Binder Jetting

-uses two materials; a powder based material and a binder.

-The binder is usually in liquid form and the build material in powder form. A print head moves horizontally along the x and y axes of the machine and deposits alternating layers of the build material and the binding material.

Material Extrusion

-Fuse deposition modelling (FDM) is a common material extrusion process and is trademarked by the company Stratasys. 

-Material is drawn through a nozzle, where it is heated and is then deposited layer by layer. The nozzle can move horizontally and a platform moves up and down vertically after each new layer is deposited.

Power Bed Fusion

- includes the following commonly used printing techniques: Direct metal laser sintering (DMLS), Electron beam melting (EBM), Selective heat sintering (SHS), Selective laser melting (SLM) and Selective laser sintering (SLS).

Sheet Lamination

-include ultrasonic additive manufacturing (UAM) and laminated object manufacturing (LOM). The Ultrasonic Additive Manufacturing process uses sheets or ribbons of metal, which are bound together using ultrasonic welding.

Directed Energy Deposition

-covers a range of terminology: ‘Laser engineered net shaping, directed light fabrication, direct metal deposition, 3D laser cladding

-It is a more complex printing process commonly used to repair or add additional material to existing components.