Alloy designations: wrought products
Table A.4 BS EN BS EN Old BS/DTD Temperature (°C) numerical chemical number designation designation Liquidus Solidus IVIdUng range Al 99.99 1 660 660 0 AW-1080A Al 99.8 1A AW-1070A …
Principal alloy designations: cast products
Table A.3 BS EN numerical designation BS EN chemical designation Old BS number ANSI designation Temperature (°C) Liquidus Solidus Melting range Al 99.5 LM0 640 658 18 AC-46100 Al Si10Cu2Fe …
Physical, mechanical and chemical properties at 20°C
Table A.2 Property Aluminium Iron Nickel Copper Titanium Crystal structure FCC BCC FCC FCC HCP Density (gm/cm3) 2.7 7.85 8.9 8.93 4.5 Melting point (°C) 660 1536 1455 1083 1670 …
British and ISO standards related to welding and aluminium
Listed below are all of the European and ISO standards that are related to the properties, composition and product forms of aluminium and its alloys. The list also includes design …
Non-destructive testing methods
NDE may be used to reveal defects that would be difficult or impossible to detect by visual examination. The techniques are used during manufacture as a quality control tool to …
Defects in arc welding
A list of weld defects and their causes is given in Table 11.1. Other defects not listed are mainly those of geometry and include misshapen and incorrectly sized welds, variable …
Weld defects and quality control
11.1 Introduction Previous chapters have covered those defects and losses in strength that may be described as arising from metallurgical effects. This chapter covers those defects that may be described …
Welder approval
While the procedure approval test is performed to demonstrate acceptable mechanical properties, the welder approval test is carried out to demonstrate that the welder has a sufficient level of skill …
Welding procedures
A welding procedure or weld procedure specification (WPS) is a written instruction that specifies materials, consumables and edge preparations for a given joint. It lists the pre - and post-weld …
Welding procedure and welder approval
10.1 Introduction Very often the decisions on how a weld should be made, filler metal and welding parameter selection are left to the welder. While this may be acceptable in …
Flash butt welding
9.6.1 Process principles As the name suggests flash butt welding is capable of making butt joints in bar-like or tubular components, L, T and X-shaped extrusions, etc. The weld is …
Seam welding
Seam welding uses a wheel-shaped electrode (Fig. 9.4) to make either a series of overlapping spot welds to form a continuously welded and leak tight seam or a number of …
Spot welding
9.4.1 Spot welding principles and parameters Spot welding is by far the most widely used variant of the resistance welding process. The basic principles of the technique are illustrated in …
Surface condition and preparation
The surface condition of the aluminium sheets is one of the most important deciding factors in achieving consistent quality of resistance spot and 9.3 Modern robotic resistance spot welding cell. …
Power sources
The power sources are normally rated in kV A at 50% duty cycle so, if the maximum primary input power available is known, it is possible to calculate the maximum …
Resistance welding processes
9.1 Introduction Resistance welding is a fusion welding process that requires the application of both heat and pressure to achieve a sound joint. The simplest form of the process is …
Friction welding
Unlike the other processes covered in this book friction welding is a solid phase pressure welding process where no actual melting of the parent metal takes place. The earliest version …
Electron beam welding
Electron beam welding is, like laser welding, a power beam process ideally suited to the welding of close square joints in a single pass. Unlike the laser beam, however, the …
Laser welding
Laser welding is being used increasingly in both the automotive and aerospace industries for the welding of a range of materials (Fig. 8.2). The laser welding of aluminium and its …
Plasma-arc welding
As described in Section 4.3 a modification to the TIG welding torch enables a strong plasma jet to be produced that has some very desirable features for both welding and …
Other welding processes
8.1 Introduction While MIG and TIG welding may be regarded as the most frequently used processes for the joining of aluminium and its alloys there are a large number of …
MIG spot welding
MIG spot welding may be used to lap weld sheets together by melting through the top sheet and fusing into the bottom sheet without moving the torch. The equipment used …
Mechanised electro-gas welding
A technique described as electro-gas welding was developed by the Alcan Company in the late 1960s but seemed to drop out of favour in the late 1990s, which is surprising …
Mechanised and robotic welding
As MIG welding is a continuously fed wire process it is very easily mechanised. The torch, having been taken out of the welder’s hand, can be used at welding currents …
Welding procedures and techniques
A set of outline welding procedures are given in Tables 7.2 and 7.3 for butt welding using either argon or helium as the shielding gas, and guidance on parameters for …
Welding consumables
7.3.1 Shielding gases The shielding gases, as with TIG welding, are the inert gases argon and helium or combinations of these two. Other, active, gases such as oxygen or nitrogen …
Process principles
The MIG welding process, illustrated in Figs. 7.1 and 7.2, as a rule uses direct current with the electrode connected to the positive pole of the power source, DC positive, …
MIG welding
7.1 Introduction The metal arc inert gas shielded process, EN process number 131, also known as MIG, MAGS or GMAW, was first used in the USA in the mid 1940s. …
TIG spot and plug welding
By overlapping two plates a spot weld can be achieved by using the DCEN TIG process to fuse through the top plate and melt into the lower plate. Initial use …
Mechanised/automatic welding
Automation or mechanisation of the TIG process can have a number of benefits. These include the ability to use faster travel speeds, resulting in less distortion and narrower heat affected …
Process principles
The basic equipment for TIG welding comprises a power source, a welding torch, a supply of an inert shield gas, a supply of filler wire and perhaps a water cooling …
TIG welding
6.1 Introduction Tungsten arc inert gas shielded welding, EN process number 144 abbreviated to TIG, TAGS or GTAW (USA), is an arc welding process that uses a non-consumable tungsten electrode …
Fatigue strength of welded joints
Fatigue, as the name suggests, is a failure mechanism where the component fails after a period of time in service where it sees a repetitive cyclic stress. Failure may occur …
Rectification of distortion
If the measures listed above are not effective, remedial measures to rectify the distortion will be necessary. These may be based upon those used for steel but great care needs …
Distortion
Residual stress due to heating and cooling of the HAZs and the contraction of the weld metal as it cools from a molten state to ambient temperature is an unavoidable …
