Mindy·Metal
A field guide to the elements

The materials that built the modern world

Strong, conductive, endlessly reshaped — metals are the quiet backbone of everything from a power line to a piece of jewelry. Here's a look at the ones we rely on most, and the numbers behind them.

Featured Alloys

Pure elements are the textbook; alloys are what you actually cut. These are the common shop steels — mild (1018), medium-carbon (1045), alloy (4140) and stainless (304) — plus free-cutting brass (C360), each with the material card to drop straight into SolidWorks (or Fusion) for simulation and CAM. SolidWorks expects SI, so e.g. 205 GPa = 2.05×10¹¹ Pa.

Alloy
Fe·C
Steel — AISI 1018
Low-carbon mild steel — the everyday choice for fabrication, welding and forming.
Properties
Density
7.87 g/cm³
Expansion α
11.7 µm/m·K
Stiffness E
200 GPa
Tensile str.
400–550 MPa
Yield str.
220–370 MPa
Hardness
120–160 HB
Melting
≈ 1515 °C
CNC Machining
Tool
3–4-flute coated carbide
Cutting speed
100–180 m/min
Spindle (Ø6)
5,500–9,500 rpm
Feed rate
500–1,400 mm/min
Chip load
0.05–0.12 mm/tooth
Depth of cut
1–3 mm (rough)
Coolant
Flood / MQL
Machinability
≈ 70 %
Finish (Ra)
0.8–1.6 µm
Soft and a touch gummy — sharp tools and clean chip evacuation prevent a torn finish.
Bending / Forming
Elongation
15–25 %
Min bend r.
0.5–1 × t
Springback
Low
The default forming and welding steel — bends and fabricates with no drama.
CAD / CAM — SolidWorks material
Mass density
7870 kg/m³
Elastic modulus
200 GPa (2.0e11 Pa)
Poisson's ratio
0.29
Shear modulus
78 GPa
Tensile strength
440 MPa
Yield strength
370 MPa
Thermal cond.
52 W/m·K
Specific heat
486 J/kg·K
Expansion coeff.
11.7 µm/m·K
Finishes
Black oxide Zinc plate Galvanize Powder coat Bluing Paint
Alloy
Fe·C
Steel — AISI 1045
Medium-carbon steel — the workhorse for shafts, gears and machined parts.
Properties
Density
7.85 g/cm³
Expansion α
11.5 µm/m·K
Stiffness E
205 GPa
Tensile str.
570–700 MPa
Yield str.
310–530 MPa
Hardness
170–200 HB (annealed)
Melting
≈ 1495 °C
CNC Machining
Tool
4-flute TiAlN-coated carbide
Cutting speed
120–200 m/min
Spindle (Ø6)
6,500–10,500 rpm
Feed rate
600–1,500 mm/min
Chip load
0.05–0.12 mm/tooth
Depth of cut
1–3 mm (rough)
Coolant
Flood
Machinability
≈ 55–65 %
Finish (Ra)
0.8–1.6 µm
Predictable and free-machining; harden after cutting if you need wear resistance.
Bending / Forming
Elongation
12–16 %
Min bend r.
1–2 × t
Springback
Moderate
Medium carbon resists tight bends — switch to mild steel (1018) for heavy forming.
CAD / CAM — SolidWorks material
Mass density
7850 kg/m³
Elastic modulus
205 GPa (2.05e11 Pa)
Poisson's ratio
0.29
Shear modulus
80 GPa
Tensile strength
625 MPa
Yield strength
530 MPa
Thermal cond.
50 W/m·K
Specific heat
486 J/kg·K
Expansion coeff.
11.5 µm/m·K
Finishes
Black oxide Zinc plate Nickel plate Powder coat Bluing Case harden Chrome Paint
Alloy
Fe·Cr·Mo
Steel — AISI 4140
Chromoly alloy steel — high strength and toughness after heat treatment; shafts and tooling.
Properties
Density
7.85 g/cm³
Expansion α
12.3 µm/m·K
Stiffness E
205 GPa
Tensile str.
655–1080 MPa
Yield str.
415–950 MPa
Hardness
197 HB → 28–35 HRC (Q&T)
Melting
≈ 1416 °C
CNC Machining
Tool
4-flute TiAlN-coated carbide
Cutting speed
90–160 m/min
Spindle (Ø6)
4,800–8,500 rpm
Feed rate
400–1,200 mm/min
Chip load
0.05–0.10 mm/tooth
Depth of cut
1–2.5 mm (rough)
Coolant
Flood
Machinability
≈ 55–65 % (annealed)
Finish (Ra)
0.8–1.6 µm
Machine it annealed, then heat-treat — cutting it hardened demands rigid setups and lower speeds.
Bending / Forming
Elongation
12–25 %
Min bend r.
2–3 × t
Springback
Moderate–high
Chosen for strength after heat treatment, not for forming — keep any bends gentle.
CAD / CAM — SolidWorks material
Mass density
7850 kg/m³
Elastic modulus
205 GPa (2.05e11 Pa)
Poisson's ratio
0.29
Shear modulus
80 GPa
Tensile strength
1020 MPa (Q&T)
Yield strength
655 MPa (Q&T)
Thermal cond.
43 W/m·K
Specific heat
473 J/kg·K
Expansion coeff.
12.3 µm/m·K
Finishes
Black oxide Hard chrome Nitride Phosphate Nickel plate Paint
Alloy
Fe·Cr·Ni
Steel — AISI 304 (stainless)
Austenitic stainless — corrosion-resistant and hygienic; food, marine and architectural work.
Properties
Density
8.00 g/cm³
Expansion α
17.3 µm/m·K
Stiffness E
193 GPa
Tensile str.
515–750 MPa
Yield str.
205–310 MPa
Hardness
≤ 201 HB (70–90 HRB)
Melting
≈ 1450 °C
CNC Machining
Tool
4-flute AlTiN-coated carbide, sharp
Cutting speed
60–120 m/min
Spindle (Ø6)
3,200–6,400 rpm
Feed rate
300–900 mm/min
Chip load
0.05–0.10 mm/tooth
Depth of cut
1–2 mm (rough)
Coolant
High-volume flood
Machinability
≈ 45 %
Finish (Ra)
0.8–1.6 µm
Work-hardens fast — constant feed, never rub or dwell, keep it flooded; 303 is the free-machining cousin.
Bending / Forming
Elongation
40–60 %
Min bend r.
0.5–1 × t
Springback
High
Very ductile and deep-draws well, but springs back hard — overbend to hit the target angle.
CAD / CAM — SolidWorks material
Mass density
8000 kg/m³
Elastic modulus
193 GPa (1.93e11 Pa)
Poisson's ratio
0.29
Shear modulus
75 GPa
Tensile strength
580 MPa
Yield strength
290 MPa
Thermal cond.
16.2 W/m·K
Specific heat
500 J/kg·K
Expansion coeff.
17.3 µm/m·K
Finishes
Brushed #4 Mirror polish Bead blast Passivate Electropolish PVD coat
Alloy
CuZn
Brass — C360
Free-cutting brass — the machinability benchmark; fittings, valves, fine parts.
Properties
Density
8.50 g/cm³
Expansion α
20.5 µm/m·K
Stiffness E
97 GPa
Tensile str.
340–470 MPa
Yield str.
125–310 MPa
Hardness
60–80 HRB
Melting
≈ 900 °C
CNC Machining
Tool
2–3-flute polished carbide / HSS
Cutting speed
150–300 m/min
Spindle (Ø6)
8,000–16,000 rpm
Feed rate
1,000–3,000 mm/min
Chip load
0.05–0.12 mm/tooth
Depth of cut
1–4 mm (rough)
Coolant
Dry or light mist
Machinability
100 % (the benchmark)
Finish (Ra)
0.4–0.8 µm
The easiest metal to cut — short chips, neutral rake, runs dry; lead does the work.
Bending / Forming
Elongation
7–25 %
Min bend r.
1.5–3 × t
Springback
Low–moderate
Free-cutting C360 forms poorly (lead kills ductility) — use cartridge brass C260 for bends.
CAD / CAM — SolidWorks material
Mass density
8500 kg/m³
Elastic modulus
97 GPa (9.7e10 Pa)
Poisson's ratio
0.31
Shear modulus
37 GPa
Tensile strength
470 MPa
Yield strength
310 MPa
Thermal cond.
115 W/m·K
Specific heat
380 J/kg·K
Expansion coeff.
20.5 µm/m·K
Finishes
Mirror polish Brushed Bright dip Lacquer Nickel plate Chrome Antique patina

SolidWorks —
Shortcuts & Techniques

These tools and default shortcuts are the same in SolidWorks 2024, 2025 and 2026 — the core modelling workflow hasn't moved in years; each release adds options inside these commands rather than relocating them. Steps assume the default interface. (Fusion 360 and others have equivalents, but this section stays SolidWorks-focused.) Identical · 2024 · 2025 · 2026

Essential shortcuts
S
Context shortcut toolbar at the cursor
Space
View orientation menu
Ctrl+7
Isometric view
F
Zoom to fit
Ctrl+drag
Copy the selection
Ctrl+C / V
Copy / paste a feature
Ctrl+B
Rebuild
Tab
Hide the body under the cursor
arrows
Rotate · Ctrl+arrows pan
Duplicate a body or feature
  1. Quickest: click the feature in the tree, Ctrl+C, click a face or plane, then Ctrl+V.
  2. With control: Insert ▸ Features ▸ Move/Copy Body, tick Copy, set the number of copies and an X/Y/Z offset.
  3. Sketch entities: select them and Ctrl+drag to drop a copy.
Array — linear pattern
  1. Features tab ▸ Linear Pattern.
  2. Under Features and Faces, pick the feature(s) to repeat.
  3. Direction 1: click an edge or axis, then set spacing and instance count.
  4. Add Direction 2 for a 2-D grid (optional).
  5. Green check to finish.
Array — circular pattern
  1. View ▸ Hide/Show ▸ Temporary Axes so you can see the centre axis.
  2. Features tab ▸ Circular Pattern.
  3. Pattern Axis: pick a circular edge or the temporary axis.
  4. Set 360°, tick Equal spacing, set the instance count.
  5. Pick the feature(s) or body, then green check.
Mirror
  1. Features tab ▸ Mirror.
  2. Mirror Face/Plane: pick a plane (e.g. Right).
  3. Features / Bodies to Mirror: select what to reflect.
  4. Green check.
Deform borders — Flex & Deform
Flex — bend, twist or taper a whole body
  1. Insert ▸ Features ▸ Flex, select the body.
  2. Choose Bending, Twisting, Tapering or Stretching.
  3. Drag the trim planes to limit the affected region, set the angle, check.
Deform — push an edge or region to a target
  1. Insert ▸ Features ▸ Deform.
  2. Curve to curve maps an edge onto a new curve; Point pushes a zone.
  3. Set the deform region / stiffness, then check.
Fold an edge — sheet metal
  1. Make it sheet metal: Insert ▸ Sheet Metal ▸ Base Flange (or Convert to Sheet Metal).
  2. Sheet Metal tab ▸ Edge Flange, click the edge to fold.
  3. Set the angle and flange length; use Edit Flange Profile to trim its shape.
  4. Green check — the bend, relief and flat pattern update automatically.
Hollow it out — Shell
  1. Insert ▸ Features ▸ Shell, set the wall thickness.
  2. Click the face(s) to leave open (those get removed); select none for a sealed hollow.
  3. Green check.
Tip
Shell before adding fillets, so the inner wall follows the rounded faces instead of fighting them.
Drive sizes with equations
  1. Tools ▸ Equations (or right-click a dimension ▸ Add Equation).
  2. Add a global variable, e.g. "wall" = 3mm.
  3. Set a dimension equal to it: click the dimension, type =, pick the variable.
Tip
Double-click a dimension and rename it, so equations read like length = 2 * width instead of D1@Sketch1.
One part, many sizes — Configurations
  1. Switch to the ConfigurationManager tab (top-left, beside the tree).
  2. Right-click the part name ▸ Add Configuration, name it (e.g. “M6”).
  3. Change dimensions or suppress features for that configuration.
Tip
For a whole size range at once, Insert ▸ Tables ▸ Design Table drives every configuration from one spreadsheet.
Combine bodies — add / cut / intersect
  1. Insert ▸ Features ▸ Combine.
  2. Add welds bodies into one; Subtract cuts tool bodies from a main body; Common keeps only the overlap.
  3. Pick the bodies, green check.
Tip
Model a stock block, then Subtract your part from a copy of it to preview exactly what the CNC removes.
Pattern along a path — curve-driven
  1. Features ▸ Pattern ▸ Curve Driven Pattern.
  2. Pick the feature to repeat.
  3. Pick an edge or sketch curve as the path; set count and spacing.
Tip
Turn on Equal spacing and Align to seed for evenly placed copies that keep the same orientation.
Edit mid-history — rollback bar
  1. Grab the blue rollback bar at the very bottom of the FeatureManager tree.
  2. Drag it up to roll the model back to an earlier point.
  3. Add a feature there — it inserts into history at that spot — then drag the bar back down.
Tip
Right-click any feature ▸ Rollback does the same jump in one click.
Mass & centre of gravity
  1. Assign material first: right-click Material in the tree ▸ Edit Material (e.g. AISI 1045 — see the alloy cards above).
  2. Tools ▸ Evaluate ▸ Mass Properties.
  3. Read mass, volume, surface area and centre of mass.
Tip
Tools ▸ Evaluate ▸ Measure gives instant distances, angles and radii straight off the model.
Select faster
  1. Right-click an edge ▸ Select Tangency to grab a whole rounded chain (perfect before filleting).
  2. Right-click ▸ Select Loop for a face's bounding edges.
  3. Buried face? Right-click ▸ Select Other, then hover the list to pick it.
Tip
Toggle the Selection Filter toolbar with F5 to grab only edges, faces or vertices.
Mouse gestures — the speed trick
  1. Hold the right mouse button and flick in a direction — a radial menu fires that command.
  2. Set them at Tools ▸ Customize ▸ Mouse Gestures (up to 12 directions, separate per sketch / part / assembly / drawing).
Tip
Map your most-used commands (sketch, extrude, fillet, isometric) and you'll model almost without leaving the mouse.
Fillet pro tips
  • Model fillets and chamfers last, as the final cosmetic features.
  • Full Round fillet (three face sets) rounds the end of a rib or boss cleanly.
  • Variable Size fillet tapers the radius along a single edge.
  • If a fillet fails, shrink the radius or move it before the feature it's clashing with.
Habits that save hours
  • Fully define sketches — they turn black; under-defined (blue) geometry drifts when you edit nearby.
  • Name features and sketches in the tree; future-you will thank you.
  • Force a full rebuild with Ctrl+Q when geometry misbehaves — plain Ctrl+B only rebuilds what changed.
  • Build symmetric parts on the origin planes so Mirror and assembly mates stay trivial.
  • One feature = one intent; many small features edit far easier than one giant sketch.
Sweep — a profile along a path
  1. Sketch the path on one plane; sketch the profile on a plane at the path's start.
  2. Insert ▸ Boss/Base ▸ Sweep (or Cut ▸ Sweep to remove material).
  3. Pick profile, then path; add guide curves or twist if needed.
Tip
Tubes, handles, gaskets and custom thread forms are all sweeps. Keep the profile small enough not to self-intersect on tight path corners.
Loft — blend between profiles
  1. Make two or more profile sketches on parallel planes.
  2. Insert ▸ Boss/Base ▸ Loft.
  3. Click each profile in order, near the same corner, so it doesn't twist; add guide curves or a centreline for control.
Tip
A round-to-square transition (e.g. a duct or a forged blank) is a classic loft. Selecting matching points keeps the surface clean.
Draft for cast & moulded parts
  1. Insert ▸ Features ▸ Draft.
  2. Set the Neutral Plane (stays fixed) and the pull direction.
  3. Set a draft angle (1–3° typical) and pick the faces to taper.
Tip
Cast, forged and injection-moulded parts need draft to release from the mould. Add it before fillets so the rounded edges inherit the taper.
Hole Wizard — proper holes
  1. Features ▸ Hole Wizard.
  2. Pick the type (counterbore, countersink, tap, pipe tap) and a standard (ISO / ANSI / DIN) and size.
  3. Switch to the Positions tab and click on the face to place each hole.
Tip
Tapped holes carry the real thread spec into the drawing and BOM — far better than a plain extruded circle.
Threads — real vs cosmetic
  1. Real geometry: Insert ▸ Features ▸ Thread — pick the edge, a thread profile and pitch.
  2. Lightweight: Insert ▸ Annotations ▸ Cosmetic Thread — no helix, but shows correctly in drawings.
Tip
Use cosmetic threads on most parts — real modelled helices are heavy and slow to rebuild. Save them for renders or thread-fit checks.
See inside — Section view
  1. Heads-up View toolbar ▸ Section View (or View ▸ Display ▸ Section View).
  2. Pick a plane, drag the offset handle to slice through.
  3. Add a second or third plane for a corner cut.
Tip
It's display-only — nothing is cut from the model. Great for checking wall thickness and internal clearances.
Reference planes & axes
  1. Features ▸ Reference Geometry ▸ Plane.
  2. Pick references: a face plus an offset, an edge plus an angle, or three points.
  3. Reference Geometry ▸ Axis for a spin axis (e.g. two planes, or a cylindrical face).
Tip
Build a plane in mid-air to start a sketch exactly where no face exists — essential for lofts and angled bosses.
Reuse edges — Convert & Offset
  1. Open a new sketch on a face.
  2. Select existing edges, then Sketch ▸ Convert Entities to project them flat into the sketch.
  3. Or Offset Entities to project them at a set distance in/out.
Tip
Converted edges stay linked to the original — change the parent and the new sketch follows. Perfect for matching mounting bosses to a housing's outline.
Engrave a part number — Split Line + Wrap
  1. Sketch your text with Tools ▸ Sketch Entities ▸ Text on a plane facing the surface.
  2. Insert ▸ Features ▸ Wrap, set Deboss (recessed) or Emboss, pick the curved face and a depth.
  3. For flat faces, an ordinary extruded cut works; Wrap is what makes it follow a cylinder.
Tip
Insert ▸ Curve ▸ Split Line projects a sketch onto a face to divide it — handy for a separate plated or knurled region.
Assemblies — find clashes
  1. Tools ▸ Evaluate ▸ Interference Detection.
  2. Run it on the whole assembly; each overlap is listed with its volume and highlighted.
  3. Use Clearance Verification to flag parts closer than a set gap.
Tip
Run this before any prototype order — catching a 0.2 mm overlap on screen is free; catching it in machined metal is not.
Top-down design (in-context)
  1. In an assembly, right-click a component ▸ Edit Part.
  2. Sketch using other parts' edges (Convert Entities) so the part fits them exactly.
  3. Exit edit — the link (an external reference, marked “→”) keeps it matched.
Tip
Powerful but use sparingly: too many in-context links make a model fragile. Lock or break references once the design settles.
Automate — record a macro
  1. Tools ▸ Macro ▸ Record.
  2. Do the repetitive steps once, then Stop and save the .swp.
  3. Replay with Run, or bind it to a toolbar button / shortcut.
Tip
Great for chores like setting view orientation, exporting a STEP, or applying your standard material and appearance in one click.
Weldments — steel frames & a cut list
  1. Draw the frame skeleton as a 3D sketch (or a layout sketch) — just the centrelines.
  2. Weldments tab ▸ Structural Member; pick a standard profile (ISO / ANSI tube, angle, channel) and click the sketch segments to sleeve them.
  3. Trim/Extend to miter the corners; add Gusset, End Cap and Weld Bead features.
Tip
A Weldment Cut List auto-tallies every member's length and profile — drop it on a drawing and it's a ready stock-cutting list for the saw.
Flat pattern → DXF for laser / waterjet
  1. On a sheet-metal part, click Flatten (or activate the Flat-Pattern in the tree).
  2. File ▸ Save As ▸ DXF/DWG and choose to export the flat pattern.
  3. In the export options, send bend lines to their own layer.
Tip
Set the part's K-factor / bend allowance to match your shop's brake first, or the flat blank comes out the wrong length. The laser cuts the outline; the bend-line layer is just reference.
Rib — stiffen without bulk
  1. Open a sketch where the rib sits and draw an open contour (just the rib's line).
  2. Features ▸ Rib; set the thickness, the direction (parallel or normal to the sketch) and any draft.
  3. Green check — it grows down to the nearest faces automatically.
Tip
Ribs add stiffness for almost no mass. On moulded parts keep a rib ≈ 0.5–0.8× the wall thickness or the outside shows a sink mark.
Edit an imported STEP — direct editing
  1. A STEP/IGES opens as one dumb body with no feature history.
  2. Direct Editing tab ▸ Move Face to shift/rotate a face, Delete Face to remove one (with Patch to heal the gap), Replace Face to re-surface.
  3. Or FeatureWorks ▸ Recognize Features to rebuild an editable tree.
Tip
Delete Face on a boss, then let it patch, is the fastest way to clean a supplier model down to just the mounting interface you care about.
Lock a sketch — relations & Fully Define
  1. As you draw, add relations: coincident, collinear, equal, symmetric, tangent, concentric.
  2. Use a centreline + Dynamic Mirror to keep symmetry automatic.
  3. Tools ▸ Sketch Tools ▸ Fully Define Sketch auto-adds the missing dimensions/relations.
Tip
Black = fully defined (stable). Blue = under-defined (will drift). Red = over-defined — delete one conflicting relation to fix it. Aim for black before you extrude.
Surfaces — rescue a bad body
  1. Build surface bodies with Extrude / Loft / Boundary Surface for shapes a solid can't do.
  2. Surface ▸ Trim the overlaps, then Knit them into one watertight quilt.
  3. Thicken the quilt (or fill it) to turn it back into a solid.
Tip
When a messy import won't thicken or boolean, delete the bad faces, rebuild them as surfaces, knit and re-thicken — the standard repair workflow.
Mates that do real work
Advanced
  1. Width centres a tab in a slot; Symmetry and Profile Center auto-centre parts.
Mechanical
  1. Gear, Rack & Pinion, Cam, Hinge and Screw mates drive realistic motion.
Tip
A Gear mate with the right ratio spins two meshing gears together so you can sanity-check a mechanism before cutting metal.
Fill Pattern — grilles & knurls
  1. Features ▸ Pattern ▸ Fill Pattern.
  2. Pick a boundary (a face or a closed sketch) to fill.
  3. Choose a layout — hex, square, circular — set spacing, and the cut shape (hole, diamond, the built-in knurl, or your own feature).
Tip
This is the clean way to do speaker grilles, vent slots and knurled grip zones — one feature instead of hundreds of holes.
Make the drawing fast
  1. Hole Callout auto-reads a Hole Wizard hole's full spec, threads included.
  2. Model Items pulls every model dimension onto the views at once.
  3. Add GD&T & datum symbols from the Annotation tab; drop a BOM and auto-balloon the views.
Tip
If you dimensioned the model cleanly, Model Items populates most of the drawing for you — then you just tidy the placement.
Defeature — share without the IP
  1. Tools ▸ Defeature.
  2. Keep the outer envelope and the interfaces; let it strip internal detail and history.
  3. Save the result as a separate, simplified body.
Tip
Send a vendor the exact fit-and-clearance envelope of a part without handing over your full feature tree.
Sensors — guard a budget
  1. Right-click Sensors in the tree ▸ Add Sensor.
  2. Track Mass Properties, a Measurement, or Interference.
  3. Set a limit; the sensor turns red and warns the moment an edit crosses it.
Tip
Pin a mass sensor on a part that has to stay under a target weight, and you'll know instantly when a change blows the budget.
Keep big assemblies quick
  1. Open components Lightweight; switch on Large Assembly Mode.
  2. Give heavy sub-assemblies a SpeedPak config — it loads only the outer faces you actually mate to.
  3. Drop the Freeze bar below settled features so they stop rebuilding.
Tip
For navigation and measuring without loading everything, open the file in Large Design Review mode.

The Essential Metals

Machining figures are typical starting points for solid-carbide tooling with a Ø6 mm cutter — surface speed (Vc) is the real spec, so treat the rpm as an example that scales with tool diameter. Stiffness and thermal expansion are close to intrinsic, but strength, elongation and bend radius swing widely with alloy and temper, so those are shown as ranges (minimum bend radius is in multiples of sheet thickness, ×t). Always tune for your material and machine.

26
Fe
Iron
The most-used metal on Earth — the basis of all steel.
Properties
Density
7.87 g/cm³
Expansion α
11.8 µm/m·K
Stiffness E
211 GPa
Tensile str.
350–550 MPa
Melting
1538 °C
CNC Machining
Tool
4-flute coated carbide
Cutting speed
100–180 m/min
Spindle (Ø6)
5,000–9,500 rpm
Feed rate
500–1,500 mm/min
Chip load
0.04–0.10 mm/tooth
Coolant
Flood / MQL
Good machinability — coated carbide handles the chips; keep it rigid.
Bending / Forming
Yield str.
250–350 MPa
Elongation
15–25 %
Min bend r.
0.5–1 × t
Springback
Low–moderate
Finishes
Black oxide Zinc plate Powder coat Bluing Paint
29
Cu
Copper
Superb conductor — the metal inside nearly every wire.
Properties
Density
8.96 g/cm³
Expansion α
16.5 µm/m·K
Stiffness E
120 GPa
Tensile str.
210–350 MPa
Melting
1085 °C
CNC Machining
Tool
2-flute polished carbide
Cutting speed
120–250 m/min
Spindle (Ø6)
6,000–13,000 rpm
Feed rate
800–2,500 mm/min
Chip load
0.05–0.10 mm/tooth
Coolant
Flood
Gummy and stringy — very sharp tools with positive rake to beat built-up edge.
Bending / Forming
Yield str.
60–300 MPa
Elongation
30–50 %
Min bend r.
0.5 × t
Springback
Low
Finishes
Mirror polish Brushed Lacquer Ni / Au plate Patina
13
Al
Aluminium
Light and rust-proof — aircraft, cans, and frames.
Properties
Density
2.70 g/cm³
Expansion α
23.1 µm/m·K
Stiffness E
69 GPa
Tensile str.
90–310 MPa
Melting
660 °C
CNC Machining
Tool
2–3-flute polished carbide
Cutting speed
250–500 m/min
Spindle (Ø6)
13,000–26,000 rpm
Feed rate
2,000–5,000 mm/min
Chip load
0.05–0.12 mm/tooth
Coolant
Flood or air blast
Excellent machinability — run fast and clear chips well so they don't weld to the tool.
Bending / Forming
Yield str.
30–270 MPa
Elongation
10–25 %
Min bend r.
1–3 × t (T6)
Springback
High (esp. T6)
Finishes
Anodise (clear / colour) Bead blast Brushed Powder coat Alodine
22
Ti
Titanium
Strength of steel at half the weight; trusted in the body.
Properties
Density
4.51 g/cm³
Expansion α
8.6 µm/m·K
Stiffness E
116 GPa
Tensile str.
340–1000 MPa
Melting
1668 °C
CNC Machining
Tool
AlTiN-coated carbide, flood coolant
Cutting speed
30–60 m/min
Spindle (Ø6)
1,600–3,200 rpm
Feed rate
150–500 mm/min
Chip load
0.04–0.08 mm/tooth
Coolant
High-pressure flood
Difficult — work-hardens fast; keep feeding, never dwell, and flood the cut to carry heat away.
Bending / Forming
Yield str.
280–880 MPa
Elongation
14–25 %
Min bend r.
2–4 × t
Springback
Very high
Finishes
Anodise (colour) Bead blast Passivate Polish PVD coat
47
Ag
Silver
The best electrical conductor of any element.
Properties
Density
10.49 g/cm³
Expansion α
18.9 µm/m·K
Stiffness E
83 GPa
Tensile str.
140–170 MPa
Melting
962 °C
CNC Machining
Tool
Sharp polished carbide / HSS
Cutting speed
120–250 m/min
Spindle (Ø6)
6,000–13,000 rpm
Feed rate
800–2,000 mm/min
Chip load
0.04–0.08 mm/tooth
Coolant
Flood / oil
Soft and prone to smearing — sharp tools and light finishing passes give the cleanest result.
Bending / Forming
Yield str.
≈ 55 MPa
Elongation
40–50 %
Min bend r.
≈ 0.5 × t
Springback
Low
Finishes
Mirror polish Satin Oxidised patina Rhodium plate
79
Au
Gold
Nearly inert — never tarnishes, prized for millennia.
Properties
Density
19.32 g/cm³
Expansion α
14.2 µm/m·K
Stiffness E
79 GPa
Tensile str.
120–220 MPa
Melting
1064 °C
CNC Machining
Tool
Very sharp carbide / diamond
Cutting speed
80–180 m/min
Spindle (Ø6)
4,000–9,500 rpm
Feed rate
500–1,500 mm/min
Chip load
0.03–0.06 mm/tooth
Coolant
Light oil
Soft and dense — diamond tooling for a mirror finish; cutting forces are tiny.
Bending / Forming
Yield str.
≈ 30 MPa
Elongation
40–50 %
Min bend r.
≈ 0.3 × t
Springback
Very low
Finishes
Mirror polish Satin Matte blast Brushed Plated

Why Metals Matter

What makes a metal a metal is a shared set of behaviours: they conduct heat and electricity, they reflect light with that characteristic lustre, and — crucially — they bend and stretch without shattering. That last trait, ductility, is why metal can be drawn into wire, rolled into sheet, and forged into almost any shape we need.

Few are used pure. Most of the metal around you is an alloy — a blend tuned for a job. Iron becomes steel with a pinch of carbon; copper becomes bronze with tin, or brass with zinc. Mixing lets us trade a little of one property for a lot of another: more strength, less corrosion, a higher melting point.

And unlike most materials, metals are almost endlessly recyclable. A steel beam or an aluminium can be melted down and reborn with little loss — which is part of why these few elements keep building, and rebuilding, the world.