Hardfacing Electrodes
SMA
AWS: SFA
EN ISO CODE:
SMA is a basic coated electrode operating on AC/DC(+) producing a tough austenitic manganese steel weld metal. The deposit work hardens in service and has excellent resistance to wear by impact. Typical applications include surfacing of parts subjected to abrasion and heavy impact as in the case of crusher jaws, bucket teeth and lips, rail crossing, etc.
Approvals
CHEMICAL COMPOSITION OF ALL WELD METAL (%)
| Element | C | Mn | Si |
Fe |
| Percent | 0.85 | 14.5 | 0.55 | Bal |
CURRENT AND PACKING DATA: AC / DC(+)
| Size (mm) | 6.3x450 | 5x450 | 4x450 | 3.15x450 |
| Current Range (Amps) | 200-270 | 160-200 | 130-160 | 90-120 |
| Weight / Carton (kgs) | 20 | 35 | 55 | 75 |
Weld Metal Hardness:
As-welded: 200-250 BHN Work hardens (under impact): 500 BHN
Precaution
1. Ensure the electrodes are dry. Re-dry the electrodes at 250-300°C for one hour.
2. While welding of austenitic manganese steel, restrict the heat input by :
a) Short arc;
b) Stringer bead;
c) Deposit in short length;
d) Intermittent welding;
e) Keeping the base material partly immersed in water.
