Due to its high strength and weather-resistant alloy composition (Cu, Cr, Ni), SMA490AW requires adjusted techniques vs. mild steel:
1. Cutting
Plasma/Laser Cutting: Preferred for clean edges; minimizes heat distortion.
Oxyfuel Cutting: Use preheating (100–150°C) to avoid cracking in thick sections (>25mm).
Shearing: Possible for thin plates (<12mm), but tool wear is higher than with carbon steel.
2. Drilling & Tapping
Tool Material: Carbide or cobalt-alloy bits to withstand hardness.
Coolant/Lubrication: Essential to reduce heat buildup and extend tool life.
Speed/Feed Rates: Reduce by 20–30% vs. mild steel to prevent work hardening.
3. Machining (Milling, Turning)
Tool Geometry: Use sharp, positive-rake-angle tools to reduce cutting forces.
Avoid Interrupted Cuts: SMA490AW's toughness can cause chatter; ensure rigid setups.
4. Key Considerations
Deburring: Remove sharp edges post-machining to prevent stress concentrations.
Post-Processing: Clean surfaces with rust-inhibiting oils if immediate welding/weathering isn't planned.
Note: SMA490AW's abrasive oxides accelerate tool wear-plan for frequent tool inspections/replacement. For critical tolerances, consult JIS G 3114 machining guidelines
