TAFE NSW -Technical and Further Education Commission www.highered.tafensw.e du.au ENMAT101A Engineering Materials and Processes Associate Degree of Applied Engineering (Renewable Energy Technologies) Lecture 25 – Methods of joining materials
Feb 24, 2016
TAFE NSW -Technical and Further Education Commission
www.highered.tafensw.edu.au
ENMAT101A Engineering Materials and ProcessesAssociate Degree of Applied Engineering (Renewable Energy Technologies)Lecture 25 – Methods of joining materials
TAFE NSW -Technical and Further Education Commission
Methods of joining materials
EMMAT101A Engineering Materials and Processes
Reference Text Section
Higgins RA & Bolton, 2510. Materials for Engineers and Technicians, 5th ed, Butterworth Heinemann
Ch 25
Reference Text Section
TAFE NSW -Technical and Further Education Commission
Methods of joining materials (Higgins 25)
EMMAT101A Engineering Materials and Processes
Joining processes can be grouped into three main groups, according tohow the joint is achieved:• Adhesives• Soldering, brazing and welding• Mechanical joining by means of fasteners
TAFE NSW -Technical and Further Education Commission
25.2 Adhesives (Higgins 25.2)
EMMAT101A Engineering Materials and Processes
Almost any material, including dissimilar materials, can be joined byadhesives.
Curing methods:Cooling – thermoplasticChemical reaction – 2 part epoxy, polyesterEvaporation: Water / solvent2 part curing. ASurface curing. Cyanoacrylate. (Super glue)Anaerobic: Hardens when air excluded. (Loctite 600 series)Chemical reaction with water / UV Light (epoxy) / heat (Bakelite)
TAFE NSW -Technical and Further Education Commission
25.2 Adhesives (Higgins 25.2)
EMMAT101A Engineering Materials and Processes
Almost any material, including dissimilar materials, can be joined byadhesives.
TAFE NSW -Technical and Further Education Commission
25.2 Adhesives (Higgins 25.2)
EMMAT101A Engineering Materials and Processes
25.2.1 Service requirementsstrength required,temperature range in service resistance to water or moisture.
The working properties of the adhesive are also important, method of preparation and use, storage-life, drying-time, odour,toxicity, Cost surface preparation large surface area
TAFE NSW -Technical and Further Education Commission
25.3 Soldering and brazing (Higgins 25.3)
EMMAT101A Engineering Materials and Processes
25.3.1 SolderingA solder must 'wet' - that is, alloy with - the metals to be joined, and,at the same time, have a freezing range which is much lower, so that thework itself is in no danger of being melted. The solder must also providea mechanically strong joint.
TAFE NSW -Technical and Further Education Commission
25.3 Soldering and brazing (Higgins 25.3)
EMMAT101A Engineering Materials and Processes
25.3.2 Brazing Above 450oC.Borax flux
Higgins
TAFE NSW -Technical and Further Education Commission
25.4 Welding (Higgins 25.4)
EMMAT101A Engineering Materials and Processes
• Arc-welding• Electrical resistance welding• Thermo-chemical welding• Radiation welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
25.5.1 Metallic-arc welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
25.5.2 Submerged-arc welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
25.5.3 Gas-shielded arc-weldingThe TIG process
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
The MIG process
Gas metal arc welding (MIG welding)
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
The CO2 process
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
25.5.4 Plasma-arc welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.5 Arc-welding processes (Higgins 25.5)
EMMAT101A Engineering Materials and Processes
25.5.5 Summary of arc-welding processes
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.1 Spot-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.2 Projection-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.3 Seam-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.4 Butt-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.5 Flash-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.6 Electro-slag welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.6 Electric resistance welding (Higgins 25.6)
EMMAT101A Engineering Materials and Processes
25.6.7 Induction welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.7 Thermo-chemical welding (Higgins 25.7)
EMMAT101A Engineering Materials and Processes
25.7.1 Oxyacetylene welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.7 Thermo-chemical welding (Higgins 25.7)
EMMAT101A Engineering Materials and Processes
25.7.2 Thermit welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.8 Radiation welding (Higgins 25.8)
EMMAT101A Engineering Materials and Processes
Electron beam25.8.1 Laser welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.9 Solid-state welding (Higgins 25.9)
EMMAT101A Engineering Materials and Processes
25.9.1 Cold-pressure welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.9 Solid-state welding (Higgins 25.9)
EMMAT101A Engineering Materials and Processes
25.9.2 Friction-welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.9 Solid-state welding (Higgins 25.9)
EMMAT101A Engineering Materials and Processes
25.9.3 Explosive welding
Higgins
TAFE NSW -Technical and Further Education Commission
25.10 Structure of welds (Higgins 25.10)
EMMAT101A Engineering Materials and Processes
Higgins
TAFE NSW -Technical and Further Education Commission
25.11 Welding of plastics (Higgins 25.11)
EMMAT101A Engineering Materials and Processes
Higgins
25.11.1 Hot-gas welding25.11.2 Seam- and spot-welding25.11.3 Electrofusion-welding25.11.4 Stitch-welding25.11.5 Jig-welding25.11.6 Friction-welding
TAFE NSW -Technical and Further Education Commission
EMMAT101A Engineering Materials and Processes
Videos
Joining MetalsSheppard, Phil. Bendigo, Vic. : Classroom Video, c2006. DVD (29 min.). An introduction to the methods of joining metals, including riveting and fusion and non-fusion methods of welding. Mt Druitt College Library: DVD 671.5/JOINJoining Metals Notes (pdf)Recommended Viewing: All sections.
TAFE NSW -Technical and Further Education Commission
EMMAT101A Engineering Materials and Processes
Wikipedia: Welding
Resources.
Ashby diagrams
TAFE NSW -Technical and Further Education Commission
Glossary
EMMAT101A Engineering Materials and Processes
Alternating CurrentArcBeadButt JointDepth of Fusion / penetrationEdge PreparationFillet WeldWeld: throat, rootFluxHeat Affected Zone Intermittent WeldMIG (GMAW)PorosityPorosityPre HeatingSeam Weld
MMAWShielding GasSlagSpot WeldSubmerged ArcTIG Welding (GTAW)ThermitFusionAnaerobicCyanoacrylateFriction weldingAdhesive shear, peel and tear
TAFE NSW -Technical and Further Education Commission
QUESTIONS: Joining of MaterialsHiggins Ch25, Newell, Timmings, Sheedy, Callister, Ashby
1. Define all glossary terms2. What type of soft solder is used for electronic work? Why?3. Describe two different types of brazing alloy.4. Describe two different arc welding processes, and name an application for each.5. Describe the electroslag welding process.6. Discuss the design of a joint for adhesive bonding. 7. Describe the heat-affected zone of a welded joint and explain how it affects the
properties of the metals being joined and the strength of the joint. 8. Describe the chemical reactions that take place during oxy-acetylene welding and
how these reactions can affect the joint. 9. Describe the composition, need for, and function of the flux coating of an arc
welding electrode.10.List the advantages and limitations of brazing compared to welding.11. An adhesive works best in shear stress. Explain why and show a sketch of a
typical adhesive joint that demonstrates this.
EMMAT101A Engineering Materials and Processes
TAFE NSW -Technical and Further Education Commission
QUESTIONS: Fibre CompositesHiggins Ch25, Newell, Timmings, Sheedy, Callister, Ashby
12.Explain why there are problems in welding of high carbon steels. Explain the need for preheating and post-welding heat treatments.
13.Give reasons for adhesives finding greater use in engineering and structural applications. Name five types of adhesives and list some of their inherent features and limitations.
EMMAT101A Engineering Materials and Processes