SMO 254 CHARACTERISTICS
These are the products that perform well in halide solutions with chloride and bromide ions present. The SMO 254 grade demonstrates the effects of localised corrosion caused by pitting, crevices and stresses. SMO 254 is a low carbon elemental material. Due to the low carbon content there is a reduced chance of carbide precipitation during heat application during welding.

MACHINABILITY
Due to the exceptionally high work hardening rate and the absence of sulphur, SMO 254 stainless steel is rather difficult to machine; however, sharp tools, powerful machines, positive feeds and a considerable amount of lubrication and slow speeds tend to give good machining results.

WELDING
Welding of stainless steel grade 254 SMO requires the use of filler metals which result in inferior tensile properties. AWS A5.14 ERNiCrMo-3 and alloy 625 are approved as filler metals. Electrodes used in the process must conform to AWS A5.11 ENiCrMo-12.

ANNEALING
The annealing temperature for this material should be 1149-1204°C (2100-2200°F) followed by water quenching.

WORKING IN EXTREME CONDITIONS
Forging, upsetting and other operations on this material can be carried out at temperatures in the range 982-1149°C (1800-2100°F). Temperatures above this range are not recommended as they will cause scaling and reduce the workability of the material. Post weld heat treatment is recommended to restore maximum corrosion resistance.

COLD FORMING
Cold forming can be carried out by any of the usual methods, but the process will be difficult due to the high work hardening rate. As a result, the material will have greater strength and toughness.

HARDENING
Heat treatment does not affect stainless steel grade 254 SMO. Only cold reduction will allow hardening.