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Precious Metal Gold 18K · supply condition

Precious Metal Gold 18K Cold Worked

Properties of the Cold Worked condition, compared with the other Gold 18K tempers.

Choose for springy clasps, pins, wire and thin sections needing maximum strength and dent resistance.

CNC machiningSheet metalSpecialty cost $$$$$

What is Gold 18K Cold Worked?

Gold 18K Cold Worked is Gold 18K supplied in the Cold Worked condition — choose for springy clasps, pins, wire and thin sections needing maximum strength and dent resistance. Gold 18K Cold Worked has a yield strength of 660 MPa (95.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 100% of precious metal grades. Elongation at break is 4% and the elastic modulus is 78 GPa (11.3 Msi). Gold 18K Cold Worked has a density of 15.5 g/cm³ (0.56 lb/in³), heavier than 77% of precious metal grades. It melts at 895°C (1,643 °F). O is the default condition FabDigit quotes; Cold Worked is available on request or by drawing note.

Advantages

  • Easy to machine — 75/100, better than 101% of precious metal grades
  • High strength — 660 MPa (95.7 ksi), better than 100% of precious metal grades
  • Polishes to a fine finish — 98/100, better than 98% of precious metal grades
  • Readily welded — 85/100, better than 93% of precious metal grades
  • Good corrosion resistance — 93/100, better than 78% of precious metal grades

Limitations

  • Limited formability — 25/100, worse than 95% of precious metal grades
  • Limited ductility — 4%, worse than 94% of precious metal grades
  • Low stiffness — 78 GPa (11.3 Msi), worse than 90% of precious metal grades
  • Limited service temperature — 200°C (392 °F), worse than 89% of precious metal grades
  • Heavy — 15.5 g/cm³ (0.56 lb/in³), worse than 77% of precious metal grades

Gold 18K Cold Worked properties

Typical room-temperature values for Gold 18K Cold Worked — 12 properties are specific to this condition; the rest are grade-level values shared by every Gold 18K temper. Each bar shows where the value sits among the precious metal grades in FabDigit's library — further right is higher.

Physical3

Gold 18K Cold Worked has a density of 15.5 g/cm³ (0.56 lb/in³), heavier than 77% of precious metal grades. It melts at 895°C (1,643 °F).

Density15.5 g/cm³0.56 lb/in³
Melting Point (Solidus)895°C1,643 °F
Liquidus Temperature920°C1,688 °F

Mechanical12

Gold 18K Cold Worked has a yield strength of 660 MPa (95.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 100% of precious metal grades. Elongation at break is 4% and the elastic modulus is 78 GPa (11.3 Msi).

Elastic (Young's) Modulus78 GPa11.3 Msi
Shear Modulus28 GPa4.1 Msi
Bulk Modulus135 GPa19.6 Msi
Poisson's Ratio0.39
Tensile Strength (Ultimate)780 MPa113 ksi
Yield Strength (0.2% offset)660 MPa95.7 ksi
Elongation at Break4%
Shear Strength470 MPa68.2 ksi
Fatigue Strength (Endurance Limit)250 MPa36.3 ksi
Hardness, Brinell220 HB
Hardness, Rockwell B97 HRB
Hardness, Vickers235 HV

Thermal6

Gold 18K Cold Worked is rated for continuous service to 200°C (392 °F). It conducts heat at 190 W/m·K (109.8 BTU/hr·ft·°F), better than 68% of precious metal grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).

Thermal Conductivity190 W/m·K110 BTU/hr·ft·°F
Specific Heat Capacity165 J/kg·K0.04 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)16 µm/m·K8.9 µin/in·°F
Latent Heat of Fusion80 J/g34.4 BTU/lb
Max Service Temperature (continuous)200°C392 °F
Min Service Temperature-200°C-328 °F

Electrical3

Gold 18K Cold Worked conducts electricity at 15 % IACS, worse than 66% of precious metal grades.

Electrical Conductivity15 % IACS
Electrical Resistivity1.1×10⁻⁷ Ω·m4.33 µΩ·in
Magnetic Responsenon-magnetic (Ni-bearing 18K white can be very weakly magnetic)

Chemical & Environmental3

Corrosion resistance is excellent (93/100), better than 78% of precious metal grades.

Galvanic Potential (seawater, vs SCE)0.25 V
Corrosion ResistanceExcellent93/100
Chemical Resistance SummaryImmune to water, alkalis, most single mineral acids and organics; attacked by aqua regia, cyanide + oxidiser, free halogens and hot concentrated HNO3/H2SO4 mixtures; Ag/Cu content allows sulfide tarnish and ammonia/chloride stress-corrosion cracking in cold-worked parts.

Sustainability4

Producing a kilogram of Gold 18K Cold Worked takes about 180,000 MJ of energy and emits 11,000 kg of CO₂ — more than 77% of precious metal grades. Typical recycled content is 30%.

Embodied Energy (primary production)180,000 MJ/kg7.74×10⁷ BTU/lb
Embodied Carbon (primary production)11,000 kg CO₂/kg
Embodied Water100,000 L/kg11,983 gal/lb
Typical Recycled Content30%

Manufacturability8

Gold 18K Cold Worked's machinability is very good (75/100, better than 101% of precious metal grades); weldability excellent (85/100); formability poor (25/100).

MachinabilityVery good75/100
Machinability Rating (AISI 1212 = 100 %)55%
WeldabilityExcellent85/100
Formability (cold)Poor25/100
CastabilityExcellent85/100
Brazeability / SolderabilityExcellent95/100
PolishabilityExcellent98/100
Anodizing Responsen/a — noble metal, no anodic oxide; decorate by plating (rhodium, Pd) or PVD instead

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Other Gold 18K tempers and conditions

Gold 18K is also supplied in 6 other conditions. The full side-by-side table is on the Gold 18K overview.

Working with Gold 18K Cold Worked

Is Gold 18K easy to machine?

Turns and engraves beautifully with sharp PCD/carbide tools, high speed, low feed and light cuts; annealed material is gummy, so half-hard stock and swarf recovery for refining are standard practice.

Can Gold 18K be welded?

Excellent with pulsed Nd:YAG/fibre laser and PUK micro-TIG using matching 18K filler; oxyacetylene brazing with graded gold solders is routine, but avoid overheating Zn-bearing casting alloys.

Can Gold 18K be formed, bent or molded?

In the annealed temper it rolls, draws, spins and stamps readily with interstage anneals at 650–700 °C; investment casting at 950–1050 °C mould temperature is the dominant route, plus SLM for complex parts.

What surface finishes work on Gold 18K?

Polishes to a mirror with tripoli/rouge and can be electroformed, rhodium- or Pd-plated (whites) and PVD coated; no anodising — ultrasonic and steam cleaning are the usual final steps.

Gold 18K chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
Au750 ‰ legal fineness minimum; refiners aim 75.2–75.5 % to stay above assay tolerance75 – 75.875
Agyellow 18K; near zero in Ni/Pd whites0 – 1612.5
Zndeoxidiser / colour and flow modifier in casting alloys0 – 40.5
Ni18K white (Au-Ni-Cu-Zn) only; restricted by EU nickel-release rules0 – 130
Pdnickel-free 18K white (Au-Pd-Ag-Cu)0 – 150
Co+Ir+Ru+Sigrain refiners / deoxidisers in casting and 3D-printing powders0 – 0.30.05
Cubalance of the 250 ‰ base metal; up to ~25 % in 18K red/rose≥ 0 (balance)

Gold 18K Cold Worked — frequently asked

What is Gold 18K Cold Worked used for?

Gold 18K Cold Worked is typically used for fine jewelry rings and bracelets, watch cases and bezels, dental crowns and inlays, decorative electronics trim, engraved medallions and awards and clasps, cufflinks and findings. In short: premium 18K jewelry gold.

What is the yield strength of Gold 18K Cold Worked?

Gold 18K Cold Worked has a typical yield strength of 660 MPa (95.7 ksi) and a tensile strength of 780 MPa (113 ksi) — stronger than 100% of precious metal grades. Strength varies by condition: see the 7 listed tempers.

Is Gold 18K Cold Worked easy to machine?

Yes — machinability is rated very good (75/100, better than 101% of precious metal grades). Turns and engraves beautifully with sharp PCD/carbide tools, high speed, low feed and light cuts; annealed material is gummy, so half-hard stock and swarf recovery for refining are standard practice.

Can Gold 18K Cold Worked be welded?

Yes — weldability is rated excellent (85/100). Excellent with pulsed Nd:YAG/fibre laser and PUK micro-TIG using matching 18K filler; oxyacetylene brazing with graded gold solders is routine, but avoid overheating Zn-bearing casting alloys.

What surface finishes work on Gold 18K Cold Worked?

Polishes to a mirror with tripoli/rouge and can be electroformed, rhodium- or Pd-plated (whites) and PVD coated; no anodising — ultrasonic and steam cleaning are the usual final steps.

Can Gold 18K Cold Worked be formed, bent or molded?

In the annealed temper it rolls, draws, spins and stamps readily with interstage anneals at 650–700 °C; investment casting at 950–1050 °C mould temperature is the dominant route, plus SLM for complex parts.

What is the maximum service temperature of Gold 18K Cold Worked?

Gold 18K Cold Worked is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in Gold 18K Cold Worked?

Yes — Gold 18K Cold Worked is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. The Metallurgy of Carat Gold Alloys / Gold Bulletin property compilationsWorld Gold Council / Springer (2004)
  2. ASM Handbook Vol. 2 — Properties of Nonferrous Alloys (Precious Metals)ASM International (1990)
  3. ISO 9202 Jewellery — Fineness of precious metal alloysISO (2019)
  4. 18K gold casting alloys and SLM powder dataCooksongold / Legor Group / Hoover & Strong (2023)
  5. CES EduPack precious-metal eco-property records (scaled to 750 ‰)Ansys Granta (2022)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.