ENMAT101A Engineering Materials and Processes
This presentation is the property of its rightful owner.
Sponsored Links
1 / 27

Mechanical Deformation of Metals PowerPoint PPT Presentation


  • 250 Views
  • Uploaded on
  • Presentation posted in: General

ENMAT101A Engineering Materials and Processes Associate Degree of Applied Engineering (Renewable Energy Technologies) Lecture 7 – Mechanical shaping of metals. Mechanical Deformation of Metals. EMMAT101A Engineering Materials and Processes. Ashby: Fig 13.2 The classes of processes.

Download Presentation

Mechanical Deformation of Metals

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Mechanical deformation of metals

ENMAT101A Engineering Materials and ProcessesAssociate Degree of Applied Engineering (Renewable Energy Technologies)Lecture 7 – Mechanical shaping of metals


Mechanical deformation of metals

Mechanical Deformation of Metals

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Ashby: Fig 13.2

The classes of processes

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes (Higgins 7.2)

Hot Working processes are carried out above the recrystallisation temperature of the material.

7.2 Hot Working Processes

7.2.1 Forging

7.2.2 Hot-rolling

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes: Forging (Higgins 7.2.1)

VIDEO:

Open-die forging can produce forgings from a kg to more than 150 tonnes.

“Open-die” means the metal is not confined laterally during forging.

The process works progressively from the starting stock into the desired shape. Flat-faced dies are usual.

Wide range of shapes and sizes are possible, especially suited to large custom parts like a ship’s propeller shaft.

Seamless Rolled Ring Forging: Starts with a cast billet, then upset and punched to form a donut shape, then rolling and squeezing (or in some cases, pounding) the donut into a thin ring. Ring diameters can be anywhere from a 100mm to 10m.

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes: Hot-Rolling (Higgins 7.2.2)

Hot Rolling (Billet to plate/sheet):

Dalarna University www.du.se

(Creative Commons)

Breaking down billets (large thick slabs cast from the furnace) into successively thinner plate, and finally sheet.

Fun and Games with Hot Rolling…

“Cobble” = British terminology

“Miss-roll = US terminology

HD-720

Cobble: http://www.youtube.com/watch?v=NnqZ-ybpdhQ

Cobble 2: http://www.youtube.com/watch?v=v4p-YCtbhMQ

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes: Extrusion (Higgins 7.2.3)

Like squeezing toothpaste from a tube, material is forced through a die and is plastically deformed into the cross-section of the die.

The die hole can be almost any shape, (e.g. a circular die will make a rod)

Mostly used for low temperature metals: copper pipes, aluminium extrusions.

Steel can only be drawn or hot rolled, but not extruded in the same way as aluminium.

Pity. Would have been a nice way to make steel pipe.

openlearn.open.ac.uk

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes: Extrusion (Higgins 7.2.3)

Extruding a hollow shape is an obvious problem. How do you hold the die that forms the hole?

Extrusion bridge die making a hollow section product.

Note: in reality, the die and ring are held together.

http://openlearn.open.ac.uk/mod/oucontent/view.php?id=399740&section=3.5

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes: Extrusion (Higgins 7.2.3)

Aluminium dominates the extrusion industry because the metal has excellent ductility without the need for extreme temperatures. It is also an obvious choice for window frames, structural and decorative parts, and almost anything of a constant cross-section.

Heated to about 900oF (480oC) to keep it well above the recrystallisation temperature (150oC).

The design of the extrusion profile effects extrusion performance. (E.g. Better to have symmetry, avoid long flats, minimize internal holes, etc…)

PBCLinear

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Hot-working processes 3 (Higgins 7.2)

Other Hot Working Processes

Hot forming of Coil Springs:

http://www.youtube.com/watch?v=6BplSiK8qK8

Friction Welding:

http://www.youtube.com/watch?v=5JbnDXw-0pM

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes (Higgins 7.3)

Cold Working processes are carried out below the recrystallisation temperature of the material.

See text:

7.3 Cold Working Processes

7.3.1 Cold-rolling

7.3.2 Drawing

7.3.3 Cold-pressing and deep-drawing

Bolts: http://www.youtube.com/watch?v=7PQyant3mCc

7.3.4 Spinning

7.3.5 Stretch-forming

7.3.6 Coining and embossing

7.3.7 Impact-extrusion

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes: Cold Rolling (Higgins 7.3.1)

Cold Rolling Steel Sheet:

Steelmaking: Cold Rolling

by CorusBCSATraining

Roll Curving Steel plate for Wind Turbine Tower

http://www.tsgnorthamerica.com

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes: Drawing(Higgins 7.3.2)

Cold Drawing of Hexagonal Bar

http://www.youtube.com/watch?v=72JWZAWZp5Q

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

Cold Pressing and Deep Drawing(Higgins 7.3.3)

Forming Bolts

http://www.youtube.com/watch?v=7PQyant3mCc

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

Spinning (Higgins 7.3.4)

Metal Spinning

http://www.youtube.com/watch?v=7PQyant3mCc

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

  • Stretch-forming (Higgins 7.3.5)

Stretch Forming

http://www.youtube.com/watch?v=eSVi7dC5L_Q

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

  • Coining and embossing (Higgins 7.3.6)

Stamping

http://www.youtube.com/watch?v=I7uBmlwxXRU

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

  • Impact Extrusion (Higgins 7.3.7)

Impact Extrusion

http://www.youtube.com/watch?v=zMhVPId-pRA

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Cold-working processes:

  • Roll Forming

Roll Forming – Roofing

http://www.youtube.com/watch?v=HrDegG_zkWY

Spiral Ductinghttp://www.youtube.com/watch?v=fIe8PQXNrUo

ERW Pipe Forming (5” or 125mm)

http://www.youtube.com/watch?v=77utCIwKSn4

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Powder Metallurgy (Higgins 7.4)

Powder Metallurgy (PM) involves pressing the powder and then heating (above recrystallisation but below the melting point) – called sintering – which binds the particles together.

See text:

7.4.1 Uses of powder-metallurgy

7.4.2 Cemented carbides

7.4.3 Sintered-bronze bearings

Powder Metallurgy

http://www.youtube.com/watch?v=_0wd8sgNIOg

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Machining metals (Higgins 7.5)

Machining is a cold-working process in which the cutting edge of a tool forms shavings or chips of the material being cut.

See text: Higgins 7.5

Machining Centre: 5 axis various jobs

http://www.youtube.com/watch?v=0LCaRqQ8Qf8

High Speed Video: Milling Cutter

http://www.youtube.com/watch?v=IUBQN1JfY80

Machining a large shaft – Lathe

http://www.youtube.com/watch?v=ObsvfP5Nrw4

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Profile Cutting

  • This is for cutting sheet material. Usually CNC

  • Laser. Fast, accurate, good finish, many materials. Finest kerf. Fussy maintenance.

  • Water jet: Almost any material. No heat damage.

High speed laser cutting

http://www.youtube.com/watch?v=RQIJSsbvolc

Water jet cutting bullet-proof glass

http://www.youtube.com/watch?v=KmUWA_oXDEQ

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Profile Cutting

  • This is for cutting sheet material. Usually CNC

  • Flame Cut (Gas): Cheaper system, good for thick steel plate. Worst quality.

  • Plasma: Better finish than flame cut, but cheaper than laser.

  • CNC router: Typically wood, plastic and soft metals (e.g. thin aluminium), often held down by vacuum onto a spoil board (MDF)

High speed laser cutting

http://www.youtube.com/watch?v=Zy3g4-D1ZeA

CNC Plasma

http://www.youtube.com/watch?v=FHUs_u27IpE

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Video

Forming & Shaping Metal

Davis, John. Warriewood, NSW : Classroom Video, c2002. DVD (22 min.)

Hot Forming, Cold Forming, Machining

Mt Druitt College Library: DVD 671.3/FORM

Recommended Viewing: All sections.

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

Online Properties Resources.

Graphical comparison of materials properties.

DoITPoMS: Dissemination of IT for the Promotion of Materials Science

Wikipedia: Materials properties

Forming: Forging, Rolling, Extrusion, Machining

CorusBCSATraining

http://www.youtube.com/user/CorusBCSATraining

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

GLOSSARY

  • Hot forming

  • Cold forming

  • Recrystallisation

  • Annealing

  • Work Hardening

  • Stress Relieving

  • Drawing

  • ERW

  • CNC

  • Profile Cutting

  • Plasma Cutting

  • Laser Cutting

  • Oxy Cutting

  • Water Jet Cutting

  • Open Die Forging

  • Upset Forging

  • Cavity Forging

Coolant

Facing

Turning

Metal Spinning

Roll Forming

Extrusion

Hot Rolling

Cold Rolling

Powder Metallurgy

Sintering

Drawing

Blanking

Bending

Stretching

EMMAT101A Engineering Materials and Processes


Mechanical deformation of metals

QUESTIONS

Callister: NA

Moodle XML: 10107 Processing

  • Define all the glossary terms.

  • Explain which type of process would be used for making railway tracks and compare it to the process of making road crash barriers. Explain the difference.

  • Why are aluminium and copper based metals extruded, but not steel.

  • Explain the process of making an ERW round pipe.

  • Make a table comparing the various profile cutting technologies. Compare machine cost, running cost, speed, accuracy, thickness, material range.

  • CNC if far superior to manual control of a machining operation. Why do we still have manual machines at all?

  • A metal gear needs to be manufactured in the tens of thousands. Compare the process options of powder metallurgy, machining, casting and forging. Include cost of die, material costs, running costs, speed, accuracy, product performance. (See: http://openlearn.open.ac.uk/mod/oucontent/view.php?id=399740&section=3.9)

EMMAT101A Engineering Materials and Processes


  • Login