Successful CNC machining of aluminum bar and plate starts with the alloy, temper, stock condition, geometry and inspection plan. “Aluminum is easy to machine” is not a specification: chip control, distortion, burrs, surface finish and tool life vary sharply between grades and tempers.
Alloy and Temper Change Machining Behavior
| Material family | Machining focus | Typical buyer question |
|---|---|---|
| 2xxx / 7xxx heat-treatable alloys | Strength, chip formation, SCC/corrosion and temper | Is the selected temper acceptable after machining? |
| 5xxx non-heat-treatable alloys | Gummy chips in softer tempers, corrosion and forming history | Will the part also be welded or exposed to marine service? |
| 6xxx heat-treatable alloys | Balanced machinability, anodizing, welding and strength | Is bar, plate or extrusion the correct starting form? |
Control Distortion Before Cutting Metal
Residual stress can be released as material is removed, causing bow or twist. Define the starting stock, stress-relieved temper where applicable, machining allowance, clamping scheme, roughing/finishing sequence and whether removal is balanced. Inspect at agreed stages rather than only after the final pass.
Burr and surface-finish control
Tool geometry, edge condition, feed, speed, coolant and workholding influence burrs and roughness. State the required Ra or other finish parameter with measurement location and direction. “Smooth finish” is not an inspectable acceptance criterion.
Do Not Treat Capacity as Guaranteed Availability
Previous page references listed processing ranges up to 15,000 mm length, 6,000 mm width and 650 mm height. These values must be reconfirmed for the actual alloy, machine, fixture, geometry and tolerance. Submit the drawing for feasibility review rather than designing around an unverified maximum.
RFQ Checklist
- 2D drawing and 3D model with revision control
- Alloy, temper, starting product form and certificate
- Critical dimensions, datum scheme, GD&T and inspection level
- Surface finish, deburring, edge break and cosmetic zones
- Coating, anodizing, marking, packaging and quantity
For plate-based parts, review the available aluminum sheet and plate products.
Post time: Mar-07-2023