Welding magnesium alloys

J.G. Young, BWRA Experience in the Wdding of Aluminum-Zinc-Magnesium Alloys, Weld. Res. SuppL, Oct 1968... 

Magnesium and Magnesium Alloys," in Rra ngManual, 3rd rev. ed., American Welding Society, Miami, Fla., 1976, Chapt. 13. 

POSTER TITLE Effect of Friction Stir Welding on the Corrosion Fatigue Performance of Magnesium Alloy AZ31B-H24... 

Aluminum and magnesium alloys are commonly friction stir welded with ambient aircooled tools and anvils. Coolant cooling of the tool is not required with aluminum, and magnesium alloys, but the coolant does provide an equilibrium tool temperature for the entire tool usage, especially for long welds, and rapid tool changes are easily performed. Midling and... 

P. Su, A. Gerlich, and T.H. North, Friction Stir Spot Welding of Aluminum and Magnesium Alloy Sheets, Paper 2005-01-1255, 2005 SAF World Congress (Detroit, Ml), Society of Automotive Engineers, 2005... 

As in most systems in which S.C.C. occurs, both applied and residual stresses are important. Welded components of magnesium alloys are normally stress-relieved after welding to reduce the residual stresses that develop during welding. 

Table I. Results of Tensile Tests of Welded Aluminum-Magnesium Alloy Plate at Low Temperatures... 

Tensile tests of notched specimens from plain and welded plate have been made to measure the notch sensitivity of aluminum-magnesium alloys at low temperatures. For the plain plate, specimens with four different notches, as shown in Fig. 2b were tested at room temperature and at -320 F. For the welded plate, Type I specimens from across the weld with the deep sharp notch machined in the center of the weld itself were tested at the same two temperatures. The results were compared with those obtained on standard 1/2 in. diameter tensile specimens (ASTM E8-57T). 

Fig. 3. Axial-stress fatigue curves for plain and welded aluminum-magnesium alloy plate.

Table II. Axial-Stress Fatigue Strengths of Plain and Welded Aluminum-Magnesium Alloy Plate at Room Temperature and —320 F...

The obvious effect of specimen geometry on strength indicates that data obtained from tests of notched specimens should be interpreted with caution. Considerably different ratios were obtained with the various notches and no one notch is wholly suitable for the evaluation of notch sensitivity under conditions other than those in this test. However, the data are sufficient to indicate that plain and welded aluminum-magnesium alloy plate is relatively insensitive to notches, at least to temperatures as low as -320 F. 

J. Sawkill and D. James, "Tear Tests on Aluminum-Magnesium Alloy Plate, British Welding Journal (November, 1958). 

Mechanical Properties of Insulating Plastic Foams at Low Temperatures (4) 132 Some Mechanical Properties of Magnesium Alloys at Low Temperatures (5) 397 Mechanical Properties of High-Strength 301 Stainless Steel Sheet at 70, -320, and -423 F in the Base Metal and Welded Joint Configurations (5) 406 The Low Temperature Mechanical Properties of Some Selected Austenitic Manganese Steels (5) 421... 

Additional filler metal can be applied separately as rod or wire. The argon shield enables aluminium, magnesium alloys and a wide range of ferrous metals to be welded without the use of a flux. 

In addition to aluminium and magnesium, TIG welding is used to weld stainless steel as well as carbon- and low-alloy steel. It is mainly used to weld thin metals... 

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