History of development of cored wires for gas-shielded welding goes back to year 1957, where first cored wires with rutile in core were introduced into market. These materials were intended for basic welding positions and weld metal had lower mechanical properties. Then came cored wires with basic filling. In 1972 were developed cored wires with rutile in core, suitable also for welding in welding positions. Cored wires with metal powder in core for the first time appeared in 1976. These cored materials are known for their excellent welding properties, low spatter and easy use in positions.
With ongoing development of cored wires, their welding and mechanical properties improved and later on cored wires of small diameters 0,9 mm appeared.
At present time, the range of cored wires for gas shielded welding differs according to type of filling:
Very interesting types of cored wires are wires with metal powder in core. Lincoln Electric firm makes cored wires Outershield MC710H, Outershield MC715-H, Outershield MC1100.
Compared to solid wires the cored wires with metal powder in core have the following advantages:
Disadvantages:
Basic type of wire Outershield MC710H is intended for welding in all positions, has excellent welding properties, noth impact strength n 47 J at 300°C. Suitable for one-layer and multi-layer welds, weld metal has less then 5 ml/H in 100g of weld metal. Characteristic feature is high melt-off. Easy arc burning in short-circuiting and pulsed welding process. Made in dia 1,2; 1,4; 1,6; 2,0; 2,4 mm. Packing of wires Outershield is 4,5kg; 15kg; 25kg; 250kg. Mechanical properties of this material are given in table 3.
Customer can choose diameter of cored wire in packing, which suits him and use lower prices of these wires in larger packing.
In table 1, there are given technical data for use of this type of wire with welding parameters and outputs. In table 2, there are given recommended parameters for welding in positions for above stated type of wire.
Another cored wire with metal powder in core is Outershield MC715, which has simillar properties as material Outershield MC710, however it has still better mechanical properties, espacially notch impact strength at low temperatures more then 47 J at 40° C.
Another cored wire with metal powder in core Outershield MC1100 is intended for welding of highstrength steels, weld metal contains less than 4 ml H in 100 g. Yield point of weld metal is 720 MPa. Breaking strength of weld metal is 815 MPa at elongation 15 21%. Mechanical properties of this material are given in table 4.
We can conclude that the use of cored wires with metal powder in core brings substantial improvement of the quality and reliability of welds, higher welding output and excellent appearance of welds in all positions.
Table 1. Melt-off rates for wire MC 710 H
Diameter (mm) |
Type of arc |
Wire feed
speed |
Current |
Voltage |
Melt-off
rate |
---|---|---|---|---|---|
1,0 |
Short-circuiting arc Spray arc |
540 975 1270 1015 1270 1780 |
80 120 150 170 220 240 |
15 17 18 27-29 29-32 31-34 |
0,9 1,6 2,0 2,5 4,1 5,8 |
1,2 |
Short-circuiting arc Spray arc |
460 655 870 635 1145 1650 |
90 120 150 180 275 340 |
15 16 17 28-30 31-34 35-38 |
1,1 1,4 1,9 2,7 4,8 6,8 |
1,4 |
Short-circuiting arc Spray arc |
205 255 280 445 890 1400 |
105 125 135 170 270 355 |
14,5 15,0 15,5 27-29 29-32 32-34 |
1,2 1,5 1,6 2,5 5,0 8,1 |
1,6 |
Short-circuiting arc Spray arc |
180 205 230 380 635 890 1145 |
145 160 170 235 325 400 460 |
15 16 18 25-26 29-32 34-37 36-38 |
1,5 1,7 1,9 2,9 5,0 7,0 9,1 |
2,0 |
Spray arc |
320 510 760 |
290 385 510 |
25-27 28-31 32-35 |
3,7 6,1 9,3 |
2,4 |
Spray arc |
400 475 550 |
28-32 28-32 30-34 |
Table 2. Recommended parameters when welding in positions for wire MC 710 H
Welding position Diameter (mm) |
Current/Voltage |
1G |
2F |
2G |
3G upward |
3G downward |
4G |
---|---|---|---|---|---|---|---|
1,0 |
(A) (V) |
210-375 25-33 |
210-375 25-33 |
150-200 16-18 |
130-150 15-17 |
150 16 |
150-200 16-18 |
1,2 |
(A) (V) |
230-380 26-36 |
230-380 26-36 |
230-300 26-30 |
130-170 15-17 |
130-170 16-17 |
140-175 16-17 |
1,4 |
(A) (V) |
240-385 26-36 |
240-385 26-36 |
240-340 26-31 |
160-180 14-15 |
160-180 14-15 |
175-185 15-16 |
1,6 |
(A) (V) |
280-460 28-36 |
280-460 28-36 |
270-300 28-30 |
-- -- |
||
2,0 |
(A) (V) |
300-510 28-33 |
300-510 28-33 |
-- -- |
|||
2,4 |
(A) (V) |
400-550 32-36 |
400-550 32-36 |
Table 3. Mechanical values of weld metal when using wire MC 710-H
Re (N/mm2) |
Rm (N/mm2) |
A (%) |
KV (J/° C) |
---|---|---|---|
480 |
550 |
30 |
50/-30° C |
Table 4.Mechanical properties of weld metal when using wire MC 1100 H
Re (N/mm2) |
Rm (N/ mm2) |
A (%) |
KV (J/° C) |
---|---|---|---|
720 |
815 |
21 |
45/-50° C |
Detail information will be given by CZ WELD team.
CZ WELD s.r.o., Pod
brizkami 800, 530 02 Pardubice, Czech Republic, tel./fax: +420 466 303 210 info@czweld.cz, http://www.czweld.cz |